What annoys me today in marketing and media that too often today then talking on hi-fi, science is replaced by bizarre belief structures and marketing fluff, leading to a decades-long stagnation of the audiophile domain. Science makes progress, pseudo-science doesn’t. Hi-fi world is filled by pseudoscience, dogma and fruitloopery to the extent that it resembles a fundamentalist religion. Loudspeaker performance hasn’t tangibly improved in forty years and vast sums are spent addressing the wrong problems.
Business for Engineers: Marketers Lie article points tout that marketing tells lies — falsehoods — things that serve to convey a false impression. Marketing’s purpose is to determining how the product will be branded, positioned, and sold. It seems that there too many snake oil rubbish products marketed in the name of hifi. It is irritating to watch the stupid people in the world be fooled.
In EEVblog #29 – Audiophile Audiophoolery video David L. Jones (from EEVBlog) cuts loose on the Golden Ear Audiophiles and all their Audiophoolery snake oil rubbish. The information presented in Dave’s unique non-scripted overly enthusiastic style! He’s an enthusiastic chap, but couldn’t agree more with many of the opinions he expressed: Directional cables, thousand dollar IEC power cables, and all that rubbish. Monster Cable gets mostered. Note what he says right at the end: “If you pay ridiculous money for these cable you will hear a difference, but don’t expect your friends to”. If you want to believe, you will.
My points on hifi-nonsense:
One of the tenets of audiophile systems is that they are assembled from components, allegedly so that the user can “choose” the best combination. This is pretty largely a myth. The main advantage of component systems is that the dealer can sell ridiculously expensive cables, hand-knitted by Peruvian virgins and soaked in snake oil, to connect it all up. Say goodbye to the noughties: Yesterday’s hi-fi biz is BUSTED, bro article asks are the days of floorstanders and separates numbered? If traditional two-channel audio does have a future, then it could be as the preserve of high resolution audio. Sony has taken the industry lead in High-Res Audio.
HIFI Cable Humbug and Snake oil etc. blog posting rightly points out that there is too much emphasis placed on spending huge sums of money on HIFI cables. Most of what is written about this subject is complete tripe. HIFI magazines promote myths about the benefits of all sorts of equipment. I am as amazed as the writer that that so called audiophiles and HIFI journalists can be fooled into thinking that very expensive speaker cables etc. improve performance. I generally agree – most of this expensive interconnect cable stuff is just plain overpriced.
I can agree that in analogue interconnect cables there are few cases where better cables can really result in cleaner sound, but usually getting any noticeable difference needs that the one you compare with was very bad yo start with (clearly too thin speaker wires with resistance, interconnect that picks interference etc..) or the equipment in the systems are so that they are overly-sensitive to cable characteristics (generally bad equipment designs can make for example cable capacitance affect 100 times or more than it should). Definitely too much snake oil. Good solid engineering is all that is required (like keep LCR low, Teflon or other good insulation, shielding if required, proper gauge for application and the distance traveled). Geometry is a factor but not in the same sense these yahoos preach and deceive.
In digital interconnect cables story is different than on those analogue interconnect cables. Generally in digital interconnect cables the communication either works, does not work or sometimes work unreliably. The digital cable either gets the bits to the other end or not, it does not magically alter the sound that goes through the cable. You need to have active electronics like digital signal processor to change the tone of the audio signal traveling on the digital cable, cable will just not do that.
But this digital interconnect cables characteristics has not stopped hifi marketers to make very expensive cable products that are marketed with unbelievable claims. Ethernet has come to audio world, so there are hifi Ethernet cables. How about 500 dollar Ethernet cable? That’s ridiculous. And it’s only 1.5 meters. Then how about $10,000 audiophile ethernet cable? Bias your dielectrics with the Dielectric-Bias ethernet cable from AudioQuest: “When insulation is unbiased, it slows down parts of the signal differently, a big problem for very time-sensitive multi-octave audio.” I see this as complete marketing crap speak. It seems that they’re made for gullible idiots. No professional would EVER waste money on those cables. Audioquest even produces iPhone sync cables in similar price ranges.
HIFI Cable insulators/supports (expensive blocks that keep cables few centimeters off the floor) are a product category I don’t get. They typically claim to offer incredible performance as well as appealing appearance. Conventional cable isolation theory holds that optimal cable performance can be achieved by elevating cables from the floor in an attempt to control vibrations and manage static fields. Typical cable elevators are made from electrically insulating materials such as wood, glass, plastic or ceramics. Most of these products claim superior performance based upon the materials or methods of elevation. I don’t get those claims.
Along with green magic markers on CDs and audio bricks is another item called the wire conditioner. The claim is that unused wires do not sound the same as wires that have been used for a period of time. I don’t get this product category. And I don’t believe claims in the line like “Natural Quartz crystals along with proprietary materials cause a molecular restructuring of the media, which reduces stress, and significantly improves its mechanical, acoustic, electric, and optical characteristics.” All sounds like just pure marketing with no real benefits.
CD no evil, hear no evil. But the key thing about the CD was that it represented an obvious leap from earlier recording media that simply weren’t good enough for delivery of post-produced material to the consumer to one that was. Once you have made that leap, there is no requirement to go further. The 16 bits of CD were effectively extended to 18 bits by the development of noise shaping, which allows over 100dB signal to noise ratio. That falls a bit short of the 140dB maximum range of human hearing, but that has never been a real goal. If you improve the digital media, the sound quality limiting problem became the transducers; the headphones and the speakers.
We need to talk about SPEAKERS: Soz, ‘audiophiles’, only IT will break the sound barrier article says that today’s loudspeakers are nowhere near as good as they could be, due in no small measure to the presence of “traditional” audiophile products. that today’s loudspeakers are nowhere near as good as they could be, due in no small measure to the presence of “traditional” audiophile products. I can agree with this. Loudspeaker performance hasn’t tangibly improved in forty years and vast sums are spent addressing the wrong problems.
We need to talk about SPEAKERS: Soz, ‘audiophiles’, only IT will break the sound barrier article makes good points on design, DSPs and the debunking of traditional hi-fi. Science makes progress, pseudo-science doesn’t. Legacy loudspeakers are omni-directional at low frequencies, but as frequency rises, the radiation becomes more directional until at the highest frequencies the sound only emerges directly forwards. Thus to enjoy the full frequency range, the listener has to sit in the so-called sweet spot. As a result legacy loudspeakers with sweet spots need extensive room treatment to soak up the deficient off-axis sound. New tools that can change speaker system designs in the future are omni-directional speakers and DSP-based room correction. It’s a scenario ripe for “disruption”.
Computers have become an integrated part of many audio setups. Back in the day integrated audio solutions in PCs had trouble earning respect. Ode To Sound Blaster: Are Discrete Audio Cards Still Worth the Investment? posting tells that it’s been 25 years since the first Sound Blaster card was introduced (a pretty remarkable feat considering the diminished reliance on discrete audio in PCs) and many enthusiasts still consider a sound card an essential piece to the PC building puzzle. It seems that in general onboard sound is finally “Good Enough”, and has been “Good Enough” for a long time now. For most users it is hard to justify the high price of special sound card on PC anymore. There are still some PCs with bad sound hardware on motherboard and buttload of cheap USB adapters with very poor performance. However, what if you want the best sound possible, the lowest noise possible, and don’t really game or use the various audio enhancements? You just want a plain-vanilla sound card, but with the highest quality audio (products typically made for music makers). You can find some really good USB solutions that will blow on-board audio out of the water for about $100 or so.
Although solid-state technology overwhelmingly dominates today’s world of electronics, vacuum tubes are holding out in two small but vibrant areas. Some people like the sound of tubes. The Cool Sound of Tubes article says that a commercially viable number of people find that they prefer the sound produced by tubed equipment in three areas: musical-instrument (MI) amplifiers (mainly guitar amps), some processing devices used in recording studios, and a small but growing percentage of high-fidelity equipment at the high end of the audiophile market. Keep those filaments lit, Design your own Vacuum Tube Audio Equipment article claims that vacuum tubes do sound better than transistors (before you hate in the comments check out this scholarly article on the topic). The difficulty is cost; tube gear is very expensive because it uses lots of copper, iron, often point-to-point wired by hand, and requires a heavy metal chassis to support all of these parts. With this high cost and relative simplicity of circuitry (compared to modern electronics) comes good justification for building your own gear. Maybe this is one of the last frontiers of do-it-yourself that is actually worth doing.
1,887 Comments
Tomi Engdahl says:
https://www.hificollective.co.uk/catalog/car250-charcroft-zfoil-resistor-p-5054.html
Tomi Engdahl says:
The first step us to determine if you have a need. You will need an oscilloscope to see IF you have the type of HF getting into your power lines that this filter could solve. If you have evidence of RF getting into your AC, then you can add this device and compare if it got better. Also check the secondaries of your power transformer. It is very possible that HF can’t get through anyway!
Audio has too many solutions looking for problems! Audio also has too many deaf and angry electricians looking to be “experts”.
As simple as possible, only as complex as necessary.
Tomi Engdahl says:
Crystal & Siltech Cable — Enjoy the Music.com CES 2017 Live Stream
https://www.youtube.com/watch?v=XqvsNqwdU28
This video is hosted by Steven R. Rochlin, a longstanding independent authority and innovator within the consumer electronics industry, who is joined by Crystal And Siltech Cable’s Edwin Rijnveld. As always, in the end what really matters is that you… enjoy the music!
Tomi Engdahl says:
Do expensive cables matter?
https://www.youtube.com/watch?v=EU0A_nr7Xts
Does it make sense to pair a high-end power cable to a less expensive integrated amplifier like Sprout, or is it a waste of money?
Viewer comments:
I once fell for all of this stuff. It is a good way to waste a lot of money! Get a system that is good enough and forget about it!
I’ve heard that none of them are UL listed. Shielding raises the temperature in the wire. My bro is an electrician. 15 amp circuit is 14 AWG. What difference is the last three feet going to make?!
a $300 power cable on a $500 amp…hell no. lol When you are in the $50,000 range…knock yourself out.
Hang on…the audio doesn’t flow along the power cable, so why? Its the power supply’s problem to filter out noise from the power source so if it doesn’t do its job, just improve the power supply design – a much cheaper solution. It doesn’t matter what the incoming AC is like if the power supply can clean it up.
Tomi Engdahl says:
https://www.facebook.com/groups/DIYAudio/permalink/4668490309883445/
There is always an obsessive care in feeding devices: hi-end power cables, hyper-filtered toroidal power supply, electrical stabilizers and much more.
I’ll tell you a secret: if it is so easy to change the sound of your device with every slight change in supply voltage/current, then the device has a very low PSRR, so it is poorly designed.
https://en.m.wikipedia.org/wiki/Power_supply_rejection_ratio
I’ll tell you another secret: if your appliance is well designed, even with the poorest power supply it will work fine.
Tomi Engdahl says:
https://electronics.stackexchange.com/questions/71214/does-solder-selection-affect-signal-quality#:~:text=As%20long%20as%20the%20solder,supposed%20to%20be%20cleaned%20off.
As long as the solder is used properly, and makes a solid connection, then the type of solder makes zero impact in audio quality. The flux inside the solder, on the other hand, can make a big impact. But here too, if used properly, it won’t matter. Basically, clean off the flux that is supposed to be cleaned off.
https://www.diyaudio.com/forums/solid-state/18929-solder-quality-adverse-effect-sound.html
I want to build an AKSA 55 or 100 Watt amplifier. I would consider myself a novice solderer. I’ve put a few of the small robotics kits together, and the AKSA PCBs look a lot larger than those
Will a less than perfect solder sound worse than a professionally soldered joint? Or is all that matters whether or not electrical contact is made?
Would a straight 60/40 lead solder be good for audio work? I don’t want to start a whole debate on the sound of silver as I inadvertently did on another board; I’m just wondering if the 60/40 mix is acceptable for audio work.
Also I’ve heard that electronics periodically need to be re-soldered. Why is this? I’m assuming this is because of the oxidation of the lead tin alloy not because of physical degredation, but I’m not certain.
Thanks in advance for any help
Standard 60/40 works fine and is just about the easist type with which to achieve a good solder joint.
Solder joint quality is indeed critical. Standard 60/40 works fine and is just about the easist type with which to achieve a good solder joint.
63/37 type solder is even nicer because it has the lowest melting temperature ~600 deg F. Even more important, because it is eutectic, when it is cooling it has no plastic state – it goes straight from liquid to solid so there much less chance of making a bad joint if it is disturbed while setting. It looks nicer too – makes a much more shiny joint than 60/40 stuff.
What do I use? 60/40 also I have been playing with some lead-free stuff but the flux in it is a bit weak and it needs a tip of about 800 deg F to melt easily. Makes ok but bad-looking joints.
I find that Multicore Savbit (60Lead/38Tin/2Copper) tins very well, is long term reliable, and as has been discussed previously on this forum is the best sounding of the lead based alloys.
To make good solder joints, good solder (see above), a good solder sponge and a good vari-temp solder station are required.
For practice, find an old TV pcb and practice re-soldering until you get it right.
If the components are clinced down onto the pcb, any movement is not an issue, and in my experience eutectic solder sounds wrong.
Multicore make 96S solder (96Tin/4Silver) and this sounds the best that I have heard, but is difficult to get right and is expensive.
Big tip – clean the solder with tissue and solvent to remove any oxides on the surface of the solder wire before soldering operations – NASA techniques as I was taught in the early 80′s.
Eric.
Lots of good advice in the thread Peter linked to. The best way to get good at soldering is to practice – a lot.
I’ve been using this 96% tin/4% silver solder exclusively for over 3 years now. It started when I needed some lead-free solder for a Tesla Coil capacitor, and RS was the only place around. After a couple thousand solder joints one weekend (not PCB!), I had gotten the hang of it. This is the stuff I use, despite its cost, for almost everything: RS cat# 64-026. It’s also available in .031″ diameter. I explicitly recall Fred D recommending it in some thread, though I no longer recall if it was sarcastic or not (it was in one of those long, drawn out sound of “X” arguments).
Good luck,
Mark
To answer your question…. YES, it does make a difference in sound. That’s a pureist point of view though and we all know that the pureists live on Pluto.
A lot of very good information but I suggest whatever solder you get you need to get good heat transfer between parts and pads. You will see the solder flow into all knids of places that you wouldn’t think it would but it follows heat. I use a good liquid flux and clean it with MEK or Acetone. 99% Isopropol alcohol works OK too. If the joint isn’t shiney, drop a small drop of liquid flux and reheat but just enough that the “ball” of solder reheats and that’s all. Then clean again. 60/40 solder will work fine for us “Earthlings” LOLOL
Good luck
Chris
Originally posted by mrfeedback
Multicore make 96S solder (96Tin/4Silver) and this sounds the best …
I have used the 96tin/4silver solder. I am glad to hear that it provides us with the best sound. By the way, I also often use 60lead/40tin solder with the approximately same results. In my opinion, with respect to the resulting sound, the important thing is making the good quality of physical and electrical connection between component lead and base metal, and using the solder material of good purity whatever it is.
I use one of two Multicore types (other brands will be similar). One is called Savbit, that’s a eutectic 63/37 with a trace of copper to protect the bit. The other is similar with about 2% silver for use when soldering silver or silver plated wire.
I’m not convinced it makes enough of a difference to get that anal about it, especially until your joints are mil-spec.
Without being anal or anything, I have found solders to sound surprisingly different.
60/38/2Cu is quite ok, 96S is rather better to my ears, and LMP drives me out of the room real quick.
On initial listening 96S might seem a little dullish sounding but on closer listening more detail is revealed compared to Savbit or 60/40, and when going back, the lead/tin solders sound wrong, and coloured.
LMP 60/38/2Silver initially sounds bright and detailed, but on extended listening I find it wrongly falsely bright/clangy, and the overall sound drives me up the wall.
Savbit is a cheap and a good compromise, and 96S the best/most pleasant in my experience.
This subject has been discussed previously and the concensus was in accord with my findings.
One member used lengths of solder wire as interconnect wires, and found these same preferences.
Eric.
Hey Eric,
I agree with you but you must admit that there is only about 2% of the worlds population who can really hear differences that 98% of us can’t. There are about 98% of “pureists” that “think” they can hear something and the other 2% of those….. WELLLLLLL…… Maybe with the right combination of gear can maybe 5% more of us hear any difference. Can I hear .009% THD? UHHH-NO! Can I hear .01%? Probably not. Can I hear 1% Yeah, probably…. but only under extreme conditions. Can I hear a difference in solder? Not unless there is a bad joint and it is causing niose or something. I’m getting to the age that the only things I care about are QUIET, RESPONSIVE, and CLEAN. No hiss, hum and lots of headroom. When a car blows up in a movie, I don’t want the pictures on the wall to buzz lightly and the speaker to rumble with distortion. I want the BOOOOOM and the pictures to come off the wall I want to feel the bass, not be annoyed by a pathetic speaker and crappy amp. When there is a silent scene, I DO NOT want to hear SHHHHHHH or HUMMMMMMMMMMM! Solder doesn’t take care of that so much….. DESIGN does……..
Best wishes,
Chris
Majority of diyAudio members seems to be from the 2%-world. Who know…?
Hey, A lot of people on the forum know about good design, as I stated. What percentage of them truly fall into this category? Not much. The people here know design for which I have great respect for. With sound or great sound, opinions are as many as the people in this forum……
Best of luck with your soldering to all….. Sometimes it’s a pain for even a seasoned veteran!
Chris
Practice practice practice…Soldering is a learned art. You will find it’s better to take your time. Let the iron do the work. Rule 1, the solder is your heat bridge, let it work for you. You will learn this quick when a dry iron won’t solder squat. Clean your iron ( I prefer a good wire mesh pad versus a wet sponge that will lower your tip temperature just when you’re ready to solder) “Tin” your iron tip and use a good quality solder. I use Kester “44″ rosin core solder (63/37). It helps to also tin (presolder) you parts; wire, leads… and remember ” the bigger the blob, the better the job” is NOT TRUE. I remember going through NASA certification and you want to talk about “anal”. This is to much, that’s not enought, that’s just right, and even with a microscope. Wait till you get to hot air then the fun really starts. Bottom line, take your time and it will save you headaches down the road. Now have fun, after all this is a hobby.
The best solder to use is the one you find easiest to work with because that’s the one that will give the best joints. A while back I was concerned about some delicate ICs that I tried a Kester specialty solder #58/245 that has a very low melt point. I’ve gotten in the habbit of using it for general use because it is so quick for both soldering and de-soldering that it compensates for fading near vision and shaky hands. (Us old geezers have to put up with a lot!)
Soldering is a process of alloying the solder into the surfaces of the parts being co-joined.
This process takes time and is critical to long term reliability.
Imo, quick lower temp soldering doesn’t do the job quite right.
Tomi Engdahl says:
Here’s the NASA-STD-8739.3 standard for soldering, as of 1997 anyway.
https://nepp.nasa.gov/DocUploads/06AA01BA-FC7E-4094-AE829CE371A7B05D/NASA-STD-8739.3.pdf
Tomi Engdahl says:
Does Solder selection affect signal quality?
https://electronics.stackexchange.com/questions/71214/does-solder-selection-affect-signal-quality
I’ve been wanting to design some circuits for audio processing. I am curious if solder plays a part in retaining signal quality. Is an exotic material or high end lead based solder worth it? Does it even make a difference? How would I objectively measure this?
7
I work in both the Pro-Audio and audiophile industry. As long as the solder is used properly, and makes a solid connection, then the type of solder makes zero impact in audio quality.
The flux inside the solder, on the other hand, can make a big impact. But here too, if used properly, it won’t matter. Basically, clean off the flux that is supposed to be cleaned off. Some flux is fine if not cleaned up. Rosin and “no clean” flux is fine left on there (mostly).
Stick to 60:40 Sn-Pb solder. It is easy to work with, and has the nice property that good joints look shiny. Solder is several times more resistive than copper. However, the distances spanned by solder are very tiny.
When soldering, try to ensure contact between the parts being soldered, if possible. Sometimes the contact is poor to nonexistent, like between the terminal of a through-hole device and the PCB copper pad through which it protrudes, particularly if it is one-sided PCB without plated holes. However, the distance is still very close, so the bridge formed by solder is very short.
In audio circuits, the impedances tend to be high. The tiny fraction of an ohm added by a bead of solder to a circuit in which the impedance is 10,000 ohms makes no difference.
Even in a power amplifier output stage where the impedances are a lot smaller, it doesn’t matter. Consider that it’s common to degenerate the emitter resistors of a complementary pair emitter follower with 0.22 ohm resistors which are effectively in series with the speaker load. Even these small 0.22 ohm resistors will swamp the resistance of their own solder joints.
(Some audiophiles will no doubt try to convince you that the junction between solder and copper causes distortion that is audible to one who possesses golden ears.)
Lead solder works fine (though it does eventually crystallize; after around 40 years it’s worth reflowing every joint!) but an unqualified recommendation to use it is bad advice. If you are building equipment for your own use, or for sale in those parts of the world where it is still allowed, go ahead.
But if you live elsewhere or aspire to selling worldwide (not so ambitious since eBay started!) then look for lead-free alternatives. Some of these contain a small percentage of silver; it may not make any difference to the sound but it it may be worth a minor selling point.
Tomi Engdahl says:
Which Solders Sound the best
https://gearspace.com/board/geekzone/1268942-solders-sound-best.html
Hi,
I am a novice audio DIYer. Now need to buy new solder for my coming DIY projects. Understanding that solders will impact sound (audio quality), I want to get our experience on this.
Through reviewing online information, I have short-listed some:
- Kester 63Sn/36Pb: Said to be neutral sounding but a bit dull. Easy to work with.
- Kester 96.5Sn/3Ag/0.5Cu : Said to be detailed sounding with good extension.
- Kester 96.3Sn/3.7Ag : Not much information on this
- MultiCore 62Sn/36Pb/2Ag
Not going to use exotic Solder such as WBT, Cardas…etc due to cost.
Very likely will go for silver containing Kester solder but some said solder shall have lead to sound “Full”.
Also, for the Kester solder, I wonder why we don’t use all Flux 245 (or 274) “no clean flux” which will be less work or headache for cleaning the flux. Are the Flux 44 or Flux 48 easier to work with or give better sound than the “no clean flux”?
Would appreciate your sharing on your experience.
Thanks
Just get something good for your needs & move on.
As a novice you would want to be expending your energies on the learning curve of achieving good quality solder joints & good technical practices.. don’t worry about possible (real, implied or imagined) minute differences in solder ‘sonics’.
There’s no shortage of good youtube tutorials on the subject (how to solder).
Fwiw I actually use WBT silver solder for my soldering jobs
, I just luvs how it flows & solidifies all shiny-like. If I was in the position of doing a lot of soldering all the time / working professionally I’d use a big ‘ol roll of Kester…
Worrying about ‘sonics’ of your solder is focussing on a miniscule dimension in the wider picture. I think most people select solder on the basis of price/availability/environmental laws maybe / workability, how it flows etc..
Good luck with your DIY projects & don’t let out the magic smoke!
Solder does not make a significant (audible) difference. There are other things more important to worry about.
Selecting a solder “for its sound” is kinda like selecting a horse “for its feathers”.
The best sounding solder joint is one that works.
The best sounding solder joint is one that works.
True dat!
…And for anyone out there who wants to study what’s REALLY important when selecting solder, here’s a good place to start:
The Fascinating World Of Solder Alloys And Metallurgy
https://hackaday.com/2019/05/30/the-fascinating-world-of-solder-alloys-and-metallurgy/
It doesn’t (if the joint is good).
…But this does not stop folks from believing that it does.
They tend to be the same “audiophools” who drop thousands of dollars into AC cables and bags of “magic marbles” (or whatnot).
The idea of “good sounding solder” doesn’t get as much play as some of that other malarkey (possibly because people who have learned to solder are more likely to know a thing or two about electronics).
So far as I know, the exact formulation of solder is rarely if ever a consideration for proper signal propagation even in far more demanding applications than audio frequency circuits. Circuit board topology and layout have a vastly greater effect (especially in RF circuits), as do parasitic capacitance, inductance, and/or resistance due to packaging technologies (again, at much higher than audio frequencies). Solder is chosen mainly for physical properties: how hot it must be to melt, how well it resists whiskers or bridging, whether it conforms to applicable environmental regulations, how much it costs, etc.
The average audio path though an analog console can run through up to 20+ feet of solder. That does affect sonics. For fun, make a 20 foot ‘cable’ run of your favorite solder formula and listen to the results.
Here in RoHS California I use Kester 48, 3% silver, 1/2% copper. For more critical spots I use their SN 96.3 with 3.7% silver, the rest tin. That is very good sounding solder yet it is very expensive. I like it better than non-RoHS WBT. It is very stiff next to tin/lead formulas and you do need o hold it further away from the iron as silver transfers heat very well.
The average audio path though an analog console can run through up to 20+ feet of solder. [...]
I know you to be quite a knowledgeable and righteous guy, so please don’t take this question the wrong way, but…
How did you arrive at that number (20 feet)?
If you’re hand-building a circuit, there’s no reason why you can’t have every conductor directly touching. If you do that, the conductivity or “sound” of the solder is irrelevant. It’s just glue.
Originally Posted by Jim Williams ➡️
The average audio path though an analog console can run through up to 20+ feet of solder. That does affect sonics.
Quote:
Originally Posted by 12ax7 ➡️
How did you arrive at that number (20 feet)?
I assume that Jimmy is talking about the tinned COPPER tracks on a pcb. They maybe tinned (for protection), but the copper ist still here. Since we are not talking about high radio frequencies (“skin effect”) most (if not all) of the audio-signal will be transferred through the copper traces.
Which opens a new field of sophisticated (audiophool) discussion:
Which copper(-alloy) tracks do you prefer on your pcb’s ?
Do they sound better if they are silver plated ?
…..
…..
Is it even appropriate to use tinned pcb’s ? I mean where the tin is melted with the copper, this becomes bronze and everything will sound like a bell ?
[...] Do they sound better if they are silver plated
I’m starting to think they sound best if you just forget they’re even there (unless something doesn’t work right)!
At Santa’s workshop, the elves can run through twenty feet of solder in a single afternoon. That’s why their shoes curl up in the front.
There seems to be less than five experienced engineers on Gearslutz who care about these “last hundredths of a percent” technical issues and discuss them intelligently. Unfortunately there are also thousands of P. T. Barnum’s suckers here who turn down this particularly tricky highway that they are not at all equipped to drive. They won’t do better mixes or spend more intelligently in audio because of these threads.
Thanks all for responding and advising information. I found the information linked by 12ax7 is quite informative about solder joints.
However, I am quite surprised that quite a number of members think solders do not affect sound/sonics or have minimal impact on sonic performance. Even some think that cables have no impact on sonics.
From my limited experience in Audio equipment (or HiFI), I have experienced (not thought nor opined) so many things that have impact on sonic performances. Cables and Solders are two of these variables.
When I was handling a pair DIY full range speakers with moderate efficiency (91db/w/m) redoing the solder joints to the drivers, I replaced the unknown solders by Kester 96.5Sn/3Ag/0.5Cu, I got immediate improvement in details and high/low extension. Also, the workmanship on solder joints (not saying cold joints) does affect sound. Too big a slump of solder adversely affect the sound.
Though I am a novice DIYer, I think I have no issue in completing a solder joint properly. I did make sure that all joints were of proper mechanical contact before soldering. However, my ears tell me that solders do affect sound quality like cables do.
Apart from those unnamed solder, I only used Kester 96.5Sn/3Ag/0.5Cu before. Therefore, I ask in the forum to seek those with experience on this.
If those are sceptical about the “Solders can affect sound quality” claim. You may use different solders in the Inter connects joins or Pre-amp signals inputs or even speaker drivers connections. Then, listen to them using higher resolution system. I think it is not difficult to tell the difference.
Thanks all for the inputs and sharing.
Originally Posted by andy2667 ➡️
From my limited experience in Audio equipment (or HiFI), I have experienced (not thought nor opined) so many things that have impact on sonic performances. Cables and Solders are two of these variables.
When I was handling a pair DIY full range speakers with moderate efficiency (91db/w/m) redoing the solder joints to the drivers, I replaced the unknown solders by Kester 96.5Sn/3Ag/0.5Cu, I got immediate improvement in details and high/low extension.
Three possible things going on here:
1 – The old solder joint was rubbish
2 – Expectation bias
3 – It really did add some extension at each end of the range.
If #3 did happen, the results ought to be measurable. So, I invite you to produce some graphs that prove your point. Simple enough – put a driver in a cabinet, solder it in with some cheap solder, and measure the frequency response.
Then, pull the driver, replace the solder, and measure again.
Keep positions, drive levels etc identical.
If the graphs show an obvious difference under those conditions, I’ll eat my hat. Really.
If the graphs show no difference, #2 is the likely suspect. Nothing to be ashamed of – the audiophiles of the world fall for it all the time.
Chris
Thanks Chris for advising.
I think it is not difficult to do a simple comparison tests to verify if solders impact sound. My ears tell me it does.
Of course different people may have different opinions and not all people would be able to hear the difference.
Thanks
No, your brain tells you it does. There’s a subtle difference.
I once read an account of someone that had gone into a HiFi shop and the sales guys were peddling expensive cables. So, the customer put on a quick demonstration for the sales guys:
- Set everything up, and told them the cheap cables were in play, with the intent to switch to the expensive cables.
- Customer made it look like the cables were switched, but the cheap cables stayed connected.
- Sales guys all agree – better soundstage, more bass depth, etc etc. The usual.
They were then invited to come and see which cables were connected.
The brain is easily fooled in a lot of different ways. I find my brain enjoys music much more once it’s had a little single malt.
Chris
Thanks Chris,
It is true. Brains play an important and tricky parts in evaluating the sonic performance. I always failed to tell the subtle differences.
For cable performance, after extensive cable testing, I actually prefer some inexpensive pro-audio cables to some low to mid price HiFi cables costing 10+ times of the pro audio cables.
That is why we use test equipment…
I can measure things that I can’t hear, but I can’t hear things that I can’t measure.
JR
Yep.
…And the corollary to this is: When your ear tells you “it’s wrong” and the test gear tells you “its right”, you have probably just measured the wrong thing!
What IS far more common to affect the sound are bad connections; switches, pots, loose connectors ect…Bad solder joints too..
Originally Posted by Bushman ➡️
[...] not all people would be able to hear the difference” is an unconscious admission that you really want to hear a difference… so you do.
…On the other hand, if WE (“the gatekeepers of audio”) only consider what “most people” can hear, then we are not really doing our jobs, are we?
Our mission should be: “Do what it takes to make it sound as good as possible”.
…But these days (with the “loudness wars”, data-compression schemes, and so forth), the mission has changed to “Fock it up as much as you can (before “most people” notice it).”
…And so it DOES concern me that by “enforcing” the “lowest common denominator” upon us all, what we have effectively done is to teach people NOT TO LISTEN!
I don’t disagree with your assessment of the current state of consumer audio.
But I hope you are not linking that subject to anything in my post.
I’m not saying “if the average human can’t hear it, it isn’t important”. I’m reacting to those in our community who claim that they hear wondrous differences between two audio conditions without blind testing to eliminate the possibility of bias.
Test gear, at least the AP stuff I have will not show any solder differences. It does measure switch issues easily. The average DPDT push switch when slightly worn will show .001~.005% THD. Hard solder it and it drops to the residuals, .0005%. Patch bays can measure all over the place. Mostly this is contamination or contact issues. Even a relay can measure differently in one position from the other.
Build a complex analog audio piece with tin/lead solder and another with a high silver content and most with decent hearing will detect the differences with complex acoustic music.
It takes about 1/4 to 1/2″ of solder (.20″) to fill an average plated-through hole on a double sided pcb. 20+ feet can be used easily on one rack piece. A large console will use many feet or pounds of solder.
Interested folks can wire up a 20 foot “cable” of your fav solder to listen to it’s effects.
Well, I’m not sure how much that has to do with what Jim said there, but…
…Since you have brought this question to the fore, it might be interesting to consider that while the tin does not “eat the copper”, it should be noted that there ARE some other very interesting things going on in a solder joint!:
The act of soldering creates what are known as “Intermetallic Compounds” (formed between the two pieces of metal being joined):
These Intermetallic Compounds are formed from the molecules of the two metal surfaces which have (by the act of soldering) been dissolved into the solder.
In other words, right there at the joint is a bit of a NEW ALLOY that you yourself create whenever you solder a joint! (And of course, this IS material through which the electrons must travel! )
…So there is obviously a whole lot more going on here than simply holding two pieces of metal together.
Quote:
Originally Posted by Jim Williams ➡️
It takes about 1/4 to 1/2″ of solder (.20″) to fill an average plated-through hole on a double sided pcb. 20+ feet can be used easily on one rack piece. A large console will use many feet or pounds of solder.
Interested folks can wire up a 20 foot “cable” of your fav solder to listen to it’s effects.
There are two major logical flaws here . . .
First, you obviously can’t correlate the amount of solder coming off the roll to the equivalent cross-sectional area of the solder alloy in the finished connection through which signal current actually flows. This is akin to conceptualizing the length of a concrete highway by imagining the total length of the river of wet concrete that flowed through the troughs off the backs of the all the trucks that delivered it to the jobsite. Maybe it’s fun to think about, but completely irrelevant.
Second . . . I think we can all agree that the subjective sound qualities of any cable would be the result of its electrical characteristics . . . even those who are of the opinion that any variations in these characteristics are inconsequential. We can also prove that a given cable’s electrical characteristics are directly related to the geometry/arrangement of its conductors and properties of the surrounding dielectrics. So even if you were to decide that raw wire solder was a good material with which to build a cable, you’d have to actually build cables out of it to even have a basis to observe its subjective sound qualities. And then if you wanted to compare various alloys of solder, you’d have to make sure that each sample used for evaluation had the same outer diameter, the same flux material, and the same arrangement of the flux within the solder wire . . . and after all this, your evaluation data would ONLY be valid for cables manufactured from solder wire, NOT for solder wire used to make connections inside equipment.
In short, simply yanking some wire solder off a roll and alligator-clipping it into a circuit simply doesn’t pass muster for any kind of valid test, subjective or objective.
If you actually want to do some valid tests on the subject . . . perhaps one approach would be to make a run of PC boards with (at least) hundreds of jumpers all in series, and a connector where they could be easily swapped in and out of a test fixture with dedicated I/O and buffer electronics to drive it. Various iterations of the jumper boards could be assembled, each with a different solder composition, and then the whole shebang could be subjectively evaluated by a pool of testers. None of the testers could of course know which jumper board was assembled with which solder (perhaps a potting compound or conformal coating would be necessary to avoid visual differentiation), and the identification nomenclature for the boards would have to be randomized for each tester (to eliminate any bias for i.e. “board A” or whatnot). After a sufficiently large number of evaluations, the results could be tabulated to see if there’s any consistent statistical preference for a given board . . . and then measurements could be performed to see if any technical correlations could be made to any subjective preferences, if indeed any are found to exist. Supposing that at this point some subjective and objective variation is found to exist . . . the required final step would be to go back and re-evaluate the test fixture and procedure, and verify that no other parameters could be found to influence the test, other than that of the solder composition.
I’ll admit that I’m probably interested enough to think about it for a little bit, or spend an hour perusing an AES paper on the subject. But to go through the effort of actually doing the experiment . . . completely out of the question. There are so many more important things to worry about . . .
propose a scientifically-conducted double-blind study comparing the following 3 items (for use as speaker cable):
1) 20 feet of “Monster Cable”
2) 20 feet of solder
3) 20 feet of coat-hanger wire
…Any predictions as to the outcome?
I had really hoped this was satire, but it wasn’t.
Maybe its something to do with modern practice? Back in the 70′s millspec and phone company soldering both required a tight physical joint sufficient to conduct the signal be made before any solder was applied.
The purpose of the solder was primarily to hold the joint in position and prevent oxidation. The involvement of the solder in signal conduction was minimal.
Even on plated through board the gap between the wire and the the plating is a few thou.
I guess one could use pin connectors and a wire wrapping tool and avoid the problem at all.
Originally Posted by Deleted 9d8db46 ➡️
Do non-conductive “solders” exist? Serious question.
I did a mid-gig Hail Mary XLR fix with super glue. That was a couple years ago and it’s still intact. So I’d say yes.
Originally Posted by norfolk martin
Your ears will not be golden enough to hear the day and night difference…….
…Well I would have assumed that if the study was indeed scientifically-conducted, the nighttime results would necessarily be averaged in with the daytime results.
Originally Posted by Jim Williams ➡️
The average audio path though an analog console can run through up to 20+ feet of solder. That does affect sonics. For fun, make a 20 foot ‘cable’ run of your favorite solder formula and listen to the results.
I’ll have to call that out as being a load of baloney.
Any wires soldered will first be looped on a connector, or pushed through a PCB putting them in direct contact or nearly direct contact where the solder only needs to bridge a small area to make contact which is paper thin. Electricity passes from point A to point B using the “path of least resistance” which means most of the connection is completed by a paper thin layer of solder that bonds the two wires.
The electricity only needs to bridge the gap between the two wires. The rest of the solder is overkill. Adding additional solder does not increase resistance or conductance. Once the solder layer matches the diameter of the leads being connected it should conduct the maximum amount of current.
If you had to bridge 20′ of space which would allow current to actually pass through that much solder then I’d have to say you have an exceptionally crappy build where some idiot used solder instead of copper to bridge gaps.
Solder doesn’t have a certain sound. That is snake oil.
Silver conducts the best. Use it if you want the best possible conductivity.
Some Wire can have more resistance than a solder joint, if
its a bad joint; or cold solder joint. the resistance goes up and
conductivity goes down. This could obviously affect the circuit
which could in turn change the sound. that’s a
defect, not in the intended design.
High resistance=VOLTAGE Drop but usually
circuits have several adjustment points to make up
for this. Or the there are gain adjustments or reductions
to make for the tiny about of added resistance…I’m guessing its
in the .0000056 Ohm range for a tiny section of solder.
This small amount of change WOULD not be calculated in such
a non-critical system. If it were needed; there would be a potentiometer
or such to trim the gain to exact specs in my view.
Think of this; its hard to find components sometimes with that small amount of tolerance (which is less than .05% mil-spec)
There are places where high-grade solder is required; High Freq. applications
being one They call it RF (real freaky) for a reason….. a solder
burr barely visible can act like an antenna at Microwave type frequency…
crazy stuff…….
Case closed.
Originally Posted by Brian M. Boykin ➡️
That’s all I’m saying. To quote Jim “at some point you have to put the test equipment down and listen.”
That sort of encapsulates most of the debate that runs on Gearslutz – the difference between the technicians ( of which I am one), who firmly believe that an audible difference is a measurable difference, and the listeners who can hear differences that do not appear to be measurable or scientifically attributable.
Without both of us sitting in the same room, hearing the same thing, it’s very hard to resolve. As someone noted in another thread, trying to describe sound in words is usually inadequate.
I’ll admit that I personally am a bit of a of cynic when it comes to the accuracy of perceptions, because I’ve spent the last 16 years as an attorney, including a fair bit of trial work in the early days. I can’t count the number of times that I have seen two credible and essentially honest people, who absolutely believe that they are telling the truth, testify as to entirely incompatible versions of what they perceived in a certain situation.
Study after study has shown that eye-witness testimony, which is often given great significance by juries, is largely unreliable. Its not because anyone consciously wants to lie or embellish, but simply that our perceptions are nowhere near as rational and reliable as we honestly believe them to be.
I’m not saying that perception is entirety unreliable, but that it really shouldn’t be heavily relied upon outside of double-blind listening tests that show more than a random coincidence of results.
Originally Posted by norfolk martin ➡️
That sort of encapsulates most of the debate that runs on Gearslutz – the difference between the technicians ( of which I am one), who firmly believe that an audible difference is a measurable difference, and the listeners who can hear differences that do not appear to be measurable or scientifically attributable.
This very old argument used to be called “meter readers” vs, “golden ears”… at least it was 40+ years ago.
Tomi Engdahl says:
https://www.psaudio.com/pauls-posts/solder/
Solder is the glue that holds our modern world together.
The trillions upon trillions of connected parts that we depend on for everything from transportation, information, entertainment, communication, and medicine—all of it—passes through solder.
Before 2006 when the European Union banned the use of lead in solder (thank you!), most connections were an amalgam of tin and lead.
Modern connections are lead-free, composed instead of tin, copper, and silver.
Tomi Engdahl says:
THE ART AND SCIENCE OF SOLDERING
https://www.gcaudio.com/tips-tricks/the-art-and-science-of-soldering/
Very Little has been written in the general audiophile press on the subject of soldering.
The object in soldering is to join two metal conductors by flowing molten metal across their surfaces. Sounds easier than it really is. In a proper joint, the solder molecules actually combine with those in the metals being joined. The term applied to this action is wetting.
Proper technique requires proper tools, and this begins with a good quality iron of the right temperature for the job. Fixed temperature irons come in various sizes or wattage’s and cost between $15.00 and $50.00, depending on quality.
The next most important element of the equation is the solder itself. For audiophile quality work this will normally be a solder containing a small percentage of silver. Most all solders contain a small inner core of flux. Flux helps the solder adhere to the work by removing oxides from the surfaces of the metals. For electronics application, only resin core solder should be used.
To begin, be sure that the metal surfaces of the work are clean, free of oils and debris that could reduce the ability of the solder to adhere. Also be certain that the tip of the soldering iron is clean and properly tinned.
A dull, rough or grainy surface texture is indicative of a solder job gone wrong, a cold solder joint has been produced, and is unacceptable. Either too little heat was used or too rapid cooling has occurred. Reheat the joint to see if you can restore the connection. If that fails, remove the old solder and start over.
If you need to repair a poor solder joint, or replace a component soldered to a PC board, you must first remove the old solder. This may be accomplished using a variety of methods. Solder removal wick or braid is the most common.
It takes practice to produce a good solder joint. I recommend that you spend some time honing your skills before attempting more important work.
Dr. A.J. van den Hul has put together what he calls “The Commandments for Optimal Soldering. ” While these recommendations were originally targeted for implementation with van den Hul products, the general guidelines put forth aptly apply is most cases. Although some of the suggestions are a bit esoteric for the average hobbyist, much can be learned from the basic techniques. It may also help you to understand some of the reasons behind the high termination costs of some of the more exotic, difficult to work interconnects and speaker cables. What follows is an amended version of those recommendations.
Properly prepare the surfaces for soldering by thoroughly cleaning them with a non-residue product such as Freon TF. It is especially important that any oils or grease be removed from the surfaces to insure proper solder adhesion.
Stripping of the insulation or jacket, should be done with a thermal stripper or very exact mechanical unit. It is very important to prevent the all to common surface damage inflicted by careless stripping. Significant sonic degradation may result from this type of conductor damage.
Soldering should be done with a silver-saturated solder or soldering device with a silver tip. The silver will improve the conductivity of the connection and decrease the tendency to oxidize over time.
The temperature of the iron should be around 300′C (approximately 550° F). This range may vary depending on what you are soldering. Lower temperatures may be recommended for more delicate operations involving IC’s and transistors. Our note: It may be difficult to find a temperature specification for some irons, especially less expensive models. More common is a wattage rating. As a general recommendation, I find that a 25 to 40 watt iron is ideal for most audio work.
A light flow of N2 or C02 during soldering is strongly recommended. The gas is to be blown over the joint being soldered through a small orifice. Our note: Obviously this step is not practical for the average audiophile, but is another reason I always recommend factory termination of the more exotic cables.
The use of a heat-sink during the soldering process is highly recommended. This will draw heat away from delicate parts or conductors. Our note: According to Mr. van den Hul, the signal transfer quality of the cable is preserved if excessive heat build-up in the conductor material is prevented.
De-flux the joint with a suitable solvent to remove all traces of resin. A cloth or small brush may be used to help remove stubborn resin deposits. The completed joint should exhibit a bright, clean appearance. A dull or uneven surface indicates a cold solder joint and will not be conducive to optimum signal transfer.
Cover the completed joint with a flexible coating of enamel (Our note: fingernail polish works well) to prevent airborne contamination or oxidation. Our note: While not necessary on most connections, this procedure is vitally important when terminating some cables to prevent air migration into the jacket opening. In these situations it is important to close this entry-way by sealing the jacket opening at the point where the conductor exits.
Conductive parts of the connector should be treated with an oxidation inhibitor. Silicone oil with a viscosity of between 150 and 200, diluted 1 to 25 with acetone, may also be used.
Tomi Engdahl says:
https://www.lejonklou.com/wp-content/uploads/2015/02/The-art-of-soldering.pdf
https://nepp.nasa.gov/DocUploads/06AA01BA-FC7E-4094-AE829CE371A7B05D/NASA-STD-8739.3.pdf
Tomi Engdahl says:
Some companies sell solders that are claimed to be optimized for audio:
Audiophile-Grade Solder
https://www.mcru.co.uk/product-category/diy-componants/audiophile-grade-solder/
Solder has to contain high levels of tin, which unfortunately is not a good conductor. We stock only the best solder available from Oyaide, WBT and Furutech, which improve soldered connections through maximising silver content whilst maintaining solder integrity.
Tomi Engdahl says:
Paul McGowan from PS audio mentioned many times in his videos that NPNs sound better. The big PS audio amps only uses them in their output stages.
Also, look at Nelson Pass schematics, many of them use only one “sex”
All early NAIM amplifiers uses only NPN. it is called quasi complementary. Characteristics would be very pleasant second harmonic and very stable. I still prefer it over the complementary designs
Tomi Engdahl says:
I’m sorry, but Paul is not somebody I would ever consider taking advice from.
His knowledge of electronics and circuits is pathetic. Can’t draw even the most simplistic of circuits.
who knows. Maybe 40 successful years in the business and an engineering degree isn’t enough to be trusted in 2021…
He also sells cable risers, so you know where his priorities lay. Haha
He is a sales man.
He is not an engineer, And watching any of his videos should make that extremely and very obviously apparent.
Engineers don’t sell snake oil because it would defy their own knowledge of electronics within reality.
he might not work as an engineer in ps audio anymore, but he is indeed an engineer.
When you are able to use your brain and make your way through the “shameless plugs” as Paul calls them, his videos are very informative.
I don’t want to be mean, but once again, you stick to the “close minded” side of things.
BTW, i follow ps audio quite a bit and never seen the cable lifters you refer to… now can we go back to npn and pnp ?
Tomi Engdahl says:
There is always an obsessive care in feeding devices: hi-end power cables, hyper-filtered toroidal power supply, electrical stabilizers and much more.
I’ll tell you a secret: if it is so easy to change the sound of your device with every slight change in supply voltage/current, then the device has a very low PSRR, so it is poorly designed.
https://en.m.wikipedia.org/wiki/Power_supply_rejection_ratio
I’ll tell you another secret: if your appliance is well designed, even with the poorest power supply it will work fine.
Tomi Engdahl says:
How do ferrite beads work on audio cables?
https://www.quora.com/How-do-ferrite-beads-work-on-audio-cables
Ferrite beads work on audio cables the same as they do on any other. A ferrite that surrounds the entire cable (i.e., ALL the conductors of the cable go through the same ferrite core or “bead”) represents a significant added inductance, but ONLY to “unbalanced” currents on the cable. Ideally, all the current on a cable going in one direction (say, from one piece of equipment to the next) is exactly matched by the same amount of current coming back on the “return” conductor. If the outbound and return currents are in fact equal and opposite, the magnetic fields they generate are also equal and opposite and cancel one another out. If that’s the case, then there’s no field for the ferrite to “work on,” and so it doesn’t represent any added inductance/impedance in the signal path. This has the effects of (a) “encouraging” the return current to come back on the intended return conductor, rather than finding another path (through the equipment safety grounds, for instance) since now that path represents the lowest impedance. In addition, (b), any “common mode” currents/noise (such as noise signals that might otherwise be inductively coupled to BOTH conductors (in the same direction) see this increased impedance in their way and are reduced in magnitude as a result. These effects contributed to reductions in both emitted and received noise on that connetion.
Tomi Engdahl says:
About Empirical Audio
Myths and Snake OIL
https://www.empiricalaudio.com/computer-audio/technical-papers/myths-and-snake-oil
A number of audio cable manufacturers have sprung-up over the last few years that are intent on proliferating myths about the technical aspects of interconnects, power cords and speaker cables. Since the staff at Empirical Audio is technical-based, we would like to dispel some of these myths for our customers here.
Power noise and Power Cords
There are a lot of expensive high-tech power cords being sold in the marketplace these days. Many of these claim to improve the delivery of AC to components by: Shielding the conductors, providing very fine stranded conductors and other magical treatments. Also, some audio power outlets are made of exotic materials and have heavy-duty contacts.
The reality is that a power cord made from 12-14 gauge solid copper is pretty good. The problem with this is that this wire is not UL approved for cords and is very inflexible indeed. Most electrical Romex runs to the outlet in question are 20-40 feet in length. The power cord adds an additional 6 feet or so, so this is a small percentage of the entire run. It turns out that typical “rubber” stranded copper power cords have significantly higher inductance than the Romex in the wall, even at the same wire gauge, so these are not recommended. Empirically, stranded rubber cords have been demonstrated to limit transient high-power currents (dynamics) compared to solid copper conductors when supplying power to typical audio power amplifiers.
Power Cord Shielding
Shielding a power cable is unadvisable. It will add significant capacitance to the cable with minimal positive benefit. If you really need this, then the shield needs to be spaced well away from the conductors (large diameter) to minimize capacitance and avoid constraining the magnetic field lines that should couple between the conductors.
Empirical testing has shown that standard shielded 14 gauge stranded power cord sounds less dynamic than unshielded 14 gauge stranded cord when used with audio components that benefit from improved cords. The impedance of the AC electrical system is extremely low and susceptibility to magnetic and RF fields is extremely low for power cables so the benefit is questionable at best. Unfortunately, some of the commercially available shielded cords appear to make some systems sound better, but are actually “tone controls” for taming badly matched or designed components. There is some benefit to shielding if you are trying to protect unshielded nearby unshielded interconnects from the fields generated by the cord itself.
Litz-Wire
Skin-effect is detrimental in that the impedance of the conductors changes with frequency instead of being constant across all frequencies. Skin-effect has been shown empirically to occur in both interconnects and speaker cables.
mplementation of Litz-Wire can vary greatly from one product to the next.
RF resonances and “pollution”
Some cable manufacturers would have you believe that RF can easily sneak into interconnects, speaker cables and power cords. Here is the reality:
Interconnect Shielding
Even in high-RF urban environments, shielding of interconnects is prudent, but not usually necessary. The shielding need only have coverage such that the shortest wavelength is attenuated by 50 dB or so. If the offending RF is television or radio, the size of the openings in the cable’s shield need only be about ¼” in diameter, which is a very sparse shield. If the offending RF is cell phones and other 800+ MHz RF, then holes in the 1/8″ range should be sufficient. Most common shields are much more dense than this, having a minimum of 90% coverage. Shields add capacitance to the interconnect, so they should be used only when absolutely necessary. A 90% coverage shield should be more than adequate for audio interconnects, unless you live next to a transmitter. Most folks can successfully use an unshielded cable, such as Kimber without any audible noise being picked-up.
Interconnect RF Resonances
RF resonances are possible on a shielded cable where the shield is not connected at one end. This has nothing to do with the shield coverage, but with the length of the “stub” antenna that is created by the un-terminated shield. If the length of the un-terminated shield is equal to ½ or ¼ wavelength of a nearby RF transmission, a small AC voltage may develop over the length of the shield. If the component driving the cable has a high enough output impedance, the shield voltage could be induced onto the conductors in the cable, which are a similar in length between the discontinuities of the RCA connectors at each end. To eliminate this possibility, a high-frequency capacitor can bridge the gap at the un-terminated end of the shield, behaving as a short at RF frequencies, but an open circuit at the highest audio frequencies.
Speaker Cable Shielding
Shielding of speaker cables is a waste of money and will probably compromise their performance. Speaker cables are driven by extremely low impedance drivers in the amplifier to a very low impedance speaker load. In this low-impedance environment, coupling of low-level high-frequency magnetic or electrical fields will be miniscule and insignificant. Shielding speaker cable can also cause an adverse performance impact by increasing the capacitance of the cable. Better not to do it.
Power Cord Shielding
Shielding of power cables serves no useful purpose. Shielding will add significant capacitance to the cable with minimal positive benefit. If you really need this, then the shield should be spaced well away from the conductors (large diameter) to minimize capacitance and avoid constraining the magnetic field lines that should couple between the conductors. Empirical testing has shown that standard shielded 14 gauge stranded power cord sounds less dynamic than unshielded 14 gauge stranded cord. The impedance of the electrical system is extremely low and susceptibility to magnetic and RF fields is extremely low for power cables so the benefit is questionable at best.
Use of Ferrites to stop RF
Several companies offer clamp-on and slide-on Ferrites. Some audio manufacturers claim that their Ferrites stop RF currents from being “picked-up” by power cords and other audio analog and digital cables. Ferrites are routinely used on computer internal and external cables to block RF. What is really happening here is that these are blocking radiated emissions from the computer so that the computer will pass FCC and foreign emission standards (CISPR, CSA). Their purpose is NOT to prevent RF from being “picked-up” by the signal wires. In some cases they have been added to internal computer cabling to attenuate radiation as a band-aid after the design is complete. These Ferrites will “round-off” the signal edges, removing much of the high-frequency content. The energy that Ferrites absorb is turned into heat as they are lossy elements.
Ferrites on Interconnects
What happens when you put one of these devices on your interconnect? It adds inductance to the cable causing it to be a low-pass filter (passes only lower frequencies). The problem is: if it is a large ferrite, or the composition is not correct, it can roll-off the high audio frequencies. Bad idea. Better to get a shielded cable if RF is suspected to be a problem. Some very small Ferrite beads, however, can be useful in taming some unshielded cables, such as the Kimber PBJ, but the ferrite should be installed on one conductor, not clamped across both.
Ferrites on Speaker Cables
What happens when Ferrites are installed on speaker cables? This is a more interesting question. Ferrites, with the right composition and size can be helpful for optimizing a speaker/cable/amplifier combination. I would avoid using the large clamp-on Ferrites used for EMI (Electro-Magnetic-Interference), since these generally add too much inductance. The Image Clarifier offered by Empirical Audio is a device that works for audio because the composition and size of the Ferrites is specifically chosen for audio cables. The Ferrite cores should be installed on one wire, not across both wires. The reason that Ferrites can improve the performance of speaker cables lies in their ability to add inductance and loss to the cable. We believe that this inductance reduces the natural resonances in a cable, which we believe can become audible through secondary effects. The ferrite creates a low-pass filter at very high frequency.
Power Filtering and Conditioning
Much attention has been given recently to both power filters and power conditioners. In general, the power line voltage should be sufficiently filtered by the input transformer and filter capacitors in a well-designed audio component so that an AC filter will be of little benefit.
Tomi Engdahl says:
Should you cover your audio inputs?
https://www.youtube.com/watch?v=1pSyuRsYRYA
A lot of audiophiles swear by the use of input shorting plugs on their unused audio inputs. Is this a good practice? What’s it trying to accomplish and does it work?
Viewer comments:
Great explanation Paul. Shorting plugs are only needed when an amplifier is poorly designed to allow itself to create noise by an unused inputs causing cross-talk into active inputs. If it can do audible cross-talk by just being unconnected, chances are that it can also cause cross-talk when having an actual signal. Get yourself a better pre-amp if you have such problem.
Really! I think the more I watch audio videos the more crazy shit people come up with but hey if you hear a difference more power to ya! Have a good day Paul my man and be safe out there in Colorado.
When I set up my lateset system I did many things including rhodium caps. Most of the things I have done make no difference in sound but they make things look nice and clean. Most systems I threw together and never care but the latest I wanted to take things to the next level.
Only shorting plugs made of unobtamium can be counted on to give you the lowest noise floor. I do agree unused phono inputs should be grounded because of the very high gain the circuitry has.
I have made my own shorting plugs.
For most equipment they are of little to no value.
Unused phono inputs are the best place to install them.
In the 1970s many amps came equipped with one magnetic phono input and one NAB tape head input. If either of these are unused, shorting plugs was used. This was to prevent noise from being heard when the selector switch was moved past these inputs. It is unnecessary on the high level inputs that are not used.
This is an easy test, put a strong sine wave or something on line A. Turn on line B while shorted. If you detect anyting like the sine wave instead of nothing, then there’s a difference.
Back in the day, the rotary input selector switch often had a “grounding” wafer that effectively shorted to ground all inputs that were not selected. This helped reduce crosstalk. For example, you have a tuner plugged in and a turntable, signal from the tuner can bleed into the phono input and can be audible in the background. I’m guessing PS Audio’s relays have a similar arrangement that shorts unused inputs to ground, I’d be surprised if they didn’t.
My Mark Levinson 326S disconnects any unused inputs from the circuit which is the best way of all. Luxman does this also and I am sure a few others.
A perfect excuse to buy more input devices!
I am not sure if this person meant ‘termination plugs’ on the output, but DEFINITELY not zero ohm shorting plugs! Since outputs are usually terminated by another audio gear in KOhms .. I doubt if any termination plugs would matter, again the switching example for the input, shorting unused inputs might make ‘some’ difference in measurement equipment but highly doubt it would make a noticeable difference in listening experience. What used to be in video field (and still is) having a number of unused 75 Ohm ins and outs needed to be ‘terminated with a 75 Ohm plug’ because that would upset the final impedance of the signal going to cameras and video recorders and such, and also on 75 Ohm coaxial antenna splitters with open ends.
It seems to me that better than a shorting plug one should use a terminating plug with a resistor between contacts. If the resistance is chosen correctly it could serve well as a shorting plug without being damaging or overheating if accidentally put on an output. 100K?…perhaps less like 1K
If adding a shorting plug makes a difference then I’d say the equipment isn’t designed properly.
On an expensive product there may be extra good rca plugs. everything gets dusty so you should use dust cover for rcs plugs? If you make something and use expensive RCA plugs then you should use dust protection. You should not use cheap cables with cheap rca plugs that can scratch the expensive rca plugs that are in a product!
Actually it a big difference FOR THE WORSE!! MY Chi-fi Audio GD sound was negatively affected when I shunted the un used RCA inputs. I was using the balanced and shunting the RCA had a clear on off affect that one need not have a golden ear to hear,.
There’s nothing too ridiculous for audiophools to believe. Bet they wear gold foil hats.
Tomi Engdahl says:
Why tube amps don’t have balanced inputs
https://www.youtube.com/watch?v=txT6-pRMOX8
If you haven’t noticed, most tube amplifiers do not have a balanced input. Paul helps us understand why.
Viewer comments:
I found (and still find) that balanced XLR offers an exactness and clarity that unbalanced can not match. But, if you seek a mellower than real life sound? Something more homogenized in effect? Balanced may not be what you seek.
For a single-ended input stereo amp. you’d have 1 tube for the 1st preamp stages, another for the 2nd preamp stages, and one for the phase-inverters.
For a balanced-input stereo amp, You’d have 2 extra tubes for the 1st and 2nd preamp stages, but you’d eliminate the phase inverters! That would be a net increase of only one tube!
Hybrid tube amps have balanced inputs! i.e, tubes on the preamp stage and solid state on the output stage! My Audreal XA6950 hybrid amp has balanced input which I do utilize !!
Hi Paul! My McIntosh MC275 Gordon Gow Commemorative reissue (No. 1) from 1993 is a true balanced amp from input thru to the output transformer. The first tube , V1, under the shield, is the phase splitter when using the RCA unbalanced mode and the tube is simply bypassed when using the balanced XLR input. You’re right that the amp needs more tubes, though, as the MC275 uses 11 tubes for its 75 WPC whereas most KT88 stereo amps usually have only 7 tubes, like a Conrad Johnson Premiere 11A. Unfortunately, the MC275 is no longer balanced when the outputs are paralleled or strapped together, not bridged, for 150 watts mono.
A 12AX7 is indeed a dual tube, as are most if not all of the 9 pin miniatures. I am dubious about the advantage of balanced circuitry unless you are running 50′ cables. Since I have never heard, and am sure I never will, otherwise identical electronics in balanced and single ended mode, I cannot say for sure.
I was skeptical until I tried it. But, at the same time the gains also depend on the environment. There’s also equipment that says balanced and is not truly balanced. You will hear Paul specify “true balanced” almost every time he mentions balanced.
It defeats the purpose of many tube amplifiers to have different tubes for the positive and negative part of the signal. The aim is purity. And purity means just one amplification element to handle the whole of the signal. Purity comes with its drawbacks. Fortunately, SET tubes match very well with some excellent high-efficiency loudspeakers, in a way that each part enable the other to perform their best.
Most valve amps with XLR inputs are not actually balanced. On the inside you will find that only one of the + pins is connected.
They add a resistor to reduce the higher balanced signal voltage to match the RCA. In practice this means that you get the convenience of being able to use a balanced cable however you don’t get any of the advantages balanced offers.
I am not sure why if you have a balanced input do you need to have an amplifier that is balanced all the way. The advantages of balanced is to have noise cancelled out in the interconnects. Once you are inside an amplifier this can be mitigated very well with a single ended circuit. You could even have a balanced input transformer based attenuator and have the secondary coil unbalanced out.
Howdy.
A lightning of inspiration struck me. Using a balanced input would eliminate the need for a phase splitter. Phase splitters are the most difficult circuits to design to produce exact mirror signals for the end pentodes / beam tetrodes.
My graphical equalizer delivers balanced outputs. Now I must update my projects agenda and attempt building a splitterless tube PA to investigate.
Regards.
To say tube amps do not have balanced circuitry does not reflect on all tube manufacturers. Majority of higher end tube manufacturers offer both RCA and balanced connections.
Tomi Engdahl says:
https://www.head-fi.org/threads/dont-get-why-audiophile-rca-cable-would-improve-sound-quality.557453/
Not a single component can improve sound quality.It can only make it less affected.
In the case with cables,cable capacitance,inductance and resistance react affecting the source output.It’s a matter of personal preference and beliefs,if objectively bad cable will make affect the sound subjectively good.Some manufacturers actually make higher-capacitance cables,for example,as the effect of loading the source output with a capacitor is fairly audible,while textbook-made cables perform all the same.
Analog is a different realm than digital; since an RCA (or coax, or a headphone) cable is actually carrying the audio signal itself, things like inductance, capacitance, resistance, and the like can alter the signal as it’s being passed along the cable. Ancillary things like end connectors, ferrites, and cable routing can also play a part in analog cable “sound”, and I consider those aspects as important as the actual cable material and construction.
Now, whether these differences make an audible impact is debatable, but as there’s the real-world possibility of much greater variance of these measurable characteristics between different analog cables utilizing different materials and construction methods, there’s a relatively strong case to be made that markedly-different cables (as related to the measurable parameters listed earlier) could give an audible signal change when compared to each other.
Strong case? I’m still waiting to see one.
The cable controversy is not a new one. We’ve had debates for over 30 years. Sensitive test gear has existed for decades. Gear that can measure things no human can perceive.
So where’s the evidence?
Keep in mind that there are huge financial rewards for demonstrating a difference. Cables have the highest margin of any audio gear. Do you see other audio gear manufacturers shying away from measurements? Go ask Sennheiser how the HD-800 stacks up against the T1. I’m sure they could give you a detailed analysis. So could Beyerdynamic. Don’t you think it a little strange that cable manufacturers run and hide when asked for technical evidence? The ones that don’t disappear take some predictable paths:
Try asking them about their margins. They’ll start talking R&D. But how do you conduct R&D when nothing can be measured?
What happens if you ask a cable manufacturer for actual measurements?
Regarding the article linked, cables do affect frequency response as measured by nick_charles, but claiming you could hear 0.02db differences is a bit like claiming that you can read size 3 font from 500 meters away. Besides, the differences in frequency response didn’t have any particular logic to them – all the cables had microscopic deviations from the norm and their price was not comparable to these deviations.
To be honest, I’m surprised people are still trying to apply science to cables when most of the major subjectivist publications have basically thrown up their hands and said “OK, we believe in effects that cause differences. that are not shown by modern science.”
Of course, the fact that these differences disappear under any formal test where they don’t know what they’re listening to doesn’t touch their credibility rolleyes.gif
A theory as to why a cable may sound different. Here is another one off the same site
http://www.analysis-plus.com/design_whyhollow.html
where they show how a hollow cable, because the electrical properties don’t change more of the music is delivered to your ears. Apparently. They still need to prove that link. They spend a lot of time showing how their cables work well (better than the rest) here
http://www.analysis-plus.com/design_whitepaper.html
and promisingly title the final paragraph The best test instrument – the ears, but again show no link, they only suggest that the ear can pick out very quiet sounds without showing they can and do so reliably in any hifi system.
Many do publish measurements and information as to how their cable measures differently. They then all suggest that difference in measurement is what makes their cable better. They also often claim superior build quality over their rivals. Both are then used to suggest better sound, but nothing more. For examples
http://www.head-fi.org/forum/thread/556398/cables-the-role-of-hype-and-the-missing-link
I worded that one badly…there’s a stronger case to be made for analog cables than digital cables changing the sound signature of the overall setup. “Strong” is of course relative, but there’s a higher probability (low as it may be) that cable carrying an analog audio signal is more likely to modify that signal than a cable carrying a digital signal. Whether that change is audible, if the change does actually exist, is another argument in itself.
I do entirely agree with your position on power cables, though. My hearing must just be too bad to distinguish that “increased airyness and shimmering sparkle” massively oversized, pretty power cables make.
Back in my ill-spent youth, we’d balance and “blueprint” engines to get more performance and reliability. Blueprinting involved tightening every bolt to exact torque specifications, keeping all clearances to spec, etc. Balancing kept vibrations our of everything that moved. The idea wasn’t that any single bolt being a bit too tight or loose or any single spark plug gap being a tad too narrow or wide would have much effect, but an engine that had everything done right would operate better than an engine with a lot of tiny imperfections. We called it tolerance stackup.
As I read these threads, I see references to very small improvements or differences in each individual component, many below the ability to hear. But I wonder if they all add up to something that is within our hearing.
In building a solar system, especially a low-voltage system, it’s critical to keep all connections to a minimum because each connection drops voltage. It’s critical to use properly sized wire because wire that is too small drops voltage. No single connection is all that critical because the voltage drops are usually very small, but they add up. With solar, we can measure the voltage drop exactly and so there is no debate.
But with audio, I’m not seeing any way people can measure the pleasure factor of music. Yes, I see frequency-response charts, but they don’t always correlate to the sound we’re looking for. Is there a way to measure warmth, transparency, detail?
I read in Robert Harley’s “High-Performance Audio Systems” that THC, while certainly capable of being measured and is certainly a good design goal, is often a misleading piece of evidence in the actual sound being reproduced because certain feedback designs can reduce distortion while degrading the actual sound quality. Some amp manufacturers would design for enhanced specs so their equipment could be more easily marketed, even though it didn’t sound as good.
It’s interesting to see that people in double-blind tests don’t seem to be able to find improvements in individual component improvements, I wonder if they can reliably hear differences when all these improvements are lumped together in a “blueprinted” system.
Warmth and transparency are all expressed in the numbers.
Regarding your idea of cumulative differences, the problem is that the differences involved here are stupidly small. Cable measurements often end up with a wonderful picture of the noise floor and various characteristics of the DAC/ADC. No cable consistently shows any “improvement” over any other cable – bar some truly microscopic differences that are so far out of the realm of audibility to be verging on farcical, cables are exactly the same.
However, just for fun, I measured the resistance in my Monster 400-series RCA cables versus the thin, stock cables that came with my Marantz CD DAC. Both cables measure one meter. The Monster cable measured 0.2 ohms. The stock cables measured 0.3 ohms. Plus, the fit of the Monster cables are much tighter, so resistance could be reduced a bit more. Maybe that’s not much difference in resistance — and I can’t hear the difference — but that’s a difference that I can measure. In theory, my amp should have to work harder to achieve the same volume with the stock cables. Couldn’t that make a difference in the SQ, even thought small?
josey said:
But with audio, I’m not seeing any way people can measure the pleasure factor of music. Yes, I see frequency-response charts, but they don’t always correlate to the sound we’re looking for. Is there a way to measure warmth, transparency, detail?
I read in Robert Harley’s “High-Performance Audio Systems” that THC, while certainly capable of being measured and is certainly a good design goal, is often a misleading piece of evidence in the actual sound being reproduced because certain feedback designs can reduce distortion while degrading the actual sound quality. Some amp manufacturers would design for enhanced specs so their equipment could be more easily marketed, even though it didn’t sound as good.
It’s interesting to see that people in double-blind tests don’t seem to be able to find improvements in individual component improvements, I wonder if they can reliably hear differences when all these improvements are lumped together in a “blueprinted” system.
Well, while we can’t really measure the “pleasure” factor or “warmness” and “transparency,” we can do null tests that test the two different components and nullify the parts that are the same. If there are substantial differences, then there is a difference…if there is no difference, then it’s not going to be affecting the “transparency” or any other things like that. On the other hand, if the measurements do match up approximately with how you perceive the sound, then that would be solid evidence that cables do in fact make a difference.
josey said:
I believe you. It seems there should be some better evidence than I’m seeing.
However, just for fun, I measured the resistance in my Monster 400-series RCA cables versus the thin, stock cables that came with my Marantz CD DAC. Both cables measure one meter. The Monster cable measured 0.2 ohms. The stock cables measured 0.3 ohms. Plus, the fit of the Monster cables are much tighter, so resistance could be reduced a bit more. Maybe that’s not much difference in resistance — and I can’t hear the difference — but that’s a difference that I can measure. In theory, my amp should have to work harder to achieve the same volume with the stock cables. Couldn’t that make a difference in the SQ, even thought small?
Well, that’s just the measurement of a spec, completely unrelated to the audio performance. The kinds of tests you’d have to run would be frequency response, impulse response and various ones like that. And you said yourself that you can’t tell the difference…meaning that if there is a difference, it is extremely small.
Oh, also, the lower the ohm rating, the higher the actual resistance. So the Monster cable is actually more resistive than the stock cable. That doesn’t really mean much by itself though…
josey said:
I read in Robert Harley’s “High-Performance Audio Systems” that THC, while certainly capable of being measured and is certainly a good design goal, is often a misleading piece of evidence in the actual sound being reproduced because certain feedback designs can reduce distortion while degrading the actual sound quality. Some amp manufacturers would design for enhanced specs so their equipment could be more easily marketed, even though it didn’t sound as good.
It’s interesting to see that people in double-blind tests don’t seem to be able to find improvements in individual component improvements, I wonder if they can reliably hear differences when all these improvements are lumped together in a “blueprinted” system.
I think you mean THD lol. Harmonic distortion is actually one of the ore useless specs out there, especially when it comes to amplifiers. 1% is considered clipping, and anything below 0.1% is generally considered inaudible. Even dirt cheap amps rarely rise above 0.05%, and I can’t say I could hope to tell an amp that’s 0.001% apart from one that’s 0.005%. Low THD also definitely tells you nothing about the sound of an amp. I generally can’t stand ICEpower amplifiers, and they are all low distortion. S/NR, channel separation, slew rate, and damping factor are more important measurements, but good measurements does NOT automatically equal good sound.
willakan said:
Not sure about that – no one measurement is the be and and end all ofc, but if everything measures well, I don’t honestly believe something could sound bad (due to what, stuff we aren’t measuring?)
Benchmark DACs have great measurements, and I do not like them a bit. Ask a speaker designer if they can model a great measuring speaker and then build it without even bothering to listen. I don’t think so.
If you don’t like the Benchmark, it being effectively perfect for all intents and purposes, I am led to two possible conclusions:
1. You expected to dislike the Benchmark and hence did. Gonna assume you’re not that closed minded smily_headphones1.gif
2. You prefer some degree of colouration in the sound. Nothing wrong with that, most people do IMO (eg I think I prefer slightly toned down bass, although not completely decided on that, and if I want an absence of excessive bass I will choose my headphone, rather than my source and amp, accordingly)
But the thing is, if you have a Benchmark you have a completely neutral, virtually perfect base from which you can have software side 24-bit EQ and DSP (at the actual digital source) to change the signature – boost bass, add tubelike distortion ect. Start with some crappy NOS DAC that a few people said “sounded musical like vinyl” (vomit) and you have nowhere to go with your high distortion overpriced piece of junk (I’m sure there are NOS DACs that sound fine, but that’s in spite of the fact they are NOS rather than due to IMO)
Surely the aim of a piece of hi-fi equipment is to deliver the music exactly as it is recorded (as the Benchmark DAC undoubtedly does) and then tone controls on your amp or DSPs or whatever can tweak the signature to your preference?
And speakers are rather more difficult to measure than cables/DACs/amps.
Well, that’s embarrassing, but I did acknowledge an ill-spent youth.
I’m not saying this is right or that I agree with it, but Robert Harley, editor-in-chief for The Absolute Sound, writes in The Complete Guide to High End Audio that cables are major players in the SQ of a system. Excerpts:
“Not only is the sound of a cable partially system-dependent, but the sonic characteristics of a specific cable will work better musically in some systems than in others.”
“…cables and interconnects need time to break in before they sound their best. Before break-in, a cable often sounds bright, hard, fatiguing, congested, and lacking in soundstage depth.”
“Even if a cable has had significant use, after a long period of not being used, it may not sound its best until you’ve put music through it for a few days.”
“The smooth cable may lose some musical information, but the high-resolution cable can sound analytical and bright.”
“Many cables overlay the treble with a coarse texture.”
But that to me is infinitely confusing, as in the words of the Audio Critic (objectivist audio publication)
“It should be obvious from the above discussion, at least to those familiar with The Audio Critic, that the Benchmark DAC1 has no sound of its own, transparently passing on to its output the quality of its input. Whatever sonic peculiarities may perchance be audible are due to the input signal, not the DAC1 circuit. Even if the circuit were a lot less perfect, that would still be the case. Absolute sonic transparency is a concept innocent audiophiles are uncomfortable with, believing that all audio components—CD players, preamplifiers, amplifiers, tuners, all of them—exhibit varying degrees of soundstaging, front-to-back depth, grain, air, etc. That it isn’t so, except in the case of loudspeakers, is a fact calmly accepted by professional engineers but not by the high-end pundits and high-end manufacturers, who would be out of business if the truth were to sink in universally.”
So hence if you don’t like the Benchmark, I am forced to conclude you simply don’t like the music as recorded. Again, it’s kinda hard to word this without coming across as an attack on your listening preferences, which it really isn’t meant to be – see earlier comments on colouration. But I can’t see how sound that is mechanically perfect can sound off unless:
1. It’s a bad recording.
2. Aforementioned variation in preferences.
3. You have decided to hate the sound in advance and are led by bias, which I already dismissed out of hand.
Having said that, would be intrigued if you could link a comprehensive set of measurements from some DACs you DO enjoy.
RCA cables do differ in meaningful terms – in EMI rejection and hum suppression
these have to do with the quality of the shield/braid and its termination to the connectors
the small leakage current from all line powered equipment will flow in part in the RCA shield/gnd so heavier Cu in the braid can make real difference in hum
good coverage and 360 degree termination of the shield braid to the the outer RCA shell also improves rejection of external RF interference
absolute cheapest moulded RCA IC can have literally a dozen strands in the “shield” with more open area in the braid (or even loose twist instead of braid) than covered and those too few strands can be gathered in pigtails to leave open loop area where they are soldered to the connector shell
“‘Exotic cables will not stop noise. Expensive cables, even if double or triple shielded, made of 100% unobtainium, and hand woven by virgins will have no significant effect on hum or buzz. Only the resistance of the grounded conductor can make a difference.’ If you have to use coax, Belden 8241F, with a low-resistance copper-braid shield, works well for audio and video.”
from:
Washington June AES – SMPTE.org
“the idea that you can achieve perfection with a $1,000 DAC is laughable”
Why? The only thing that separates the Benchmark from the DACs that the stereophile reviewers state are “surely better” is price. It seems strange that people have an expectation that good audio costs ludicrous amounts of money. Why shouldn’t the Benchmark be transparent? All the numbers say so, and the puported differences in sound all disappear when testing is done in an appropriately scientific way.
Why are the claims of the Audio Critic so unreasonable? Sound degradation can be split into three types: frequency response deviation, standard distortion (encompassing THD and IMD) and time-based error (such as jitter). If all these factors are addressed, you have something that should by all means sound great. Why should a DAC whose only provable distinction over such pathetic cheap crap as the Benchmark is a monstrous price tag sound better? Why should amps that all measure superbly sound different – unless their sound can be attributed to some kind of pleasurable distortion, or more likely here expectations based on the price tag.
The problem is, this is the point where I have to come out and state my opinion that these differences are largely due to bias/placebo/whatever you want to call it on the part of the listener, at which point it seems that I am implying that the listener is an idiot and people get very offended. If I now try to justify how succumbing to these biases is only human, I just come across as a pompous, patronising twit (going for another word there, but I suspect that might break the profanity rules smile.gif
)
I don’t get a “kick” out of any of this – I don’t sit at home giggling hysterically at the high end audio market and inviting audio engineers around for cocktail parties where we take turns to take cheapshots at the extremes of audiophilia. I just find the idea that something unmeasurable pervades high end audio, that can only be heard in casual listening conditions where sighted bias is very much acting upon the listener, rather difficult to believe in, to put it mildly.
EDIT: Resistors calibrated to 0.0002%? What a total waste of time!
A lot of the things people “hear” from cables, amplifiers, capacitors, DACs, etc, disappears in blind testing. I have come to the conclusion that a lot of the “differences” people hear in various components are related to a kind of placebo effect.
I really wish the Amazing Randi would offer his $1 million prize again re: hearing the difference in speaker or RCA cables- I would love to see Michael Fremer try to prove he can hear the difference between different copper wires.
(Of course he’d have to do the test with speakers cables that are JUST WIRE- no fair using speaker cables that have capacitors and inductors in them, as some fancy cables do. They actually have “networks” in them- filters, really. In other words, some cables have fixed tone controls built into them. For that you pay extra- a GREAT DEAL extra.)
If you want to see what I think is some REAL snake oil, go to the Machina Dynamica site. They have products there that I can not believe they are allowed to sell under the fraud statutes- for example, the “Teleportation Tweak” – where you pay them $60 and they call your home or cell phone and play some kind of signal over the phone. You don’t have to feed the tone into your hi fi or anything, the signal just has to be sent to your phone. Your audio or video gear doesn’t even need to be turned on.
Here’s what they claim this phone signal will do:
“The Teleportation Tweak has a profound effect on the sound of your system: (1) Clearer, (2) More information, (3) Greater frequency extension and (4) Lower distortion. ”
“The Teleportation Tweak will also improve any video system in your house, including plasma, HDTV and high end projection systems — better contrast, color saturation, color fidelity and definition.”
josey said:
Well, that’s embarrassing, but I did acknowledge an ill-spent youth.
I’m not saying this is right or that I agree with it, but Robert Harley, editor-in-chief for The Absolute Sound, writes in The Complete Guide to High End Audio that cables are major players in the SQ of a system. Excerpts:
“Not only is the sound of a cable partially system-dependent, but the sonic characteristics of a specific cable will work better musically in some systems than in others.”
“…cables and interconnects need time to break in before they sound their best. Before break-in, a cable often sounds bright, hard, fatiguing, congested, and lacking in soundstage depth.”
“Even if a cable has had significant use, after a long period of not being used, it may not sound its best until you’ve put music through it for a few days.”
“The smooth cable may lose some musical information, but the high-resolution cable can sound analytical and bright.”
“Many cables overlay the treble with a coarse texture.”
Thing is, all of the above can be explained by Robert Harley’s own reaction to cables. He only suggests the difference he hears is inherant in the cable, he cannot provide any evidence to show that is the case.
Absolutely. He provided no evidence. But don’t you find it mind-blowing that a person near the top of his profession, a person who reviews the best audio equipment for a living, the author of multiple technical audio books filled with the science of sound reproduction — a person who has to be familiar with this debate — can find such clear evidence for the performance enhancement of high-end cables?
Without claiming any difference, he will be out of business. In today’s electronics, equipment manufacturers no longer do any critical design. all designs are done by semiconductor companies. And because of investment involved, (typically $5 to $10M), the have to sell it to a broad market. Without making any esoteric claims, how are “high end” audio equipment companies going to justify the large price difference?
Is it a coincidence that all these cable talks started right after CD is invented?
Without making any esoteric claims, how are “high end” audio equipment companies going to justify the large price difference?
That’s the old problem of product differentiation. Apparently there still are too many who can make equipment that employs state of the art engineering, performs well, is flexible in meeting the user’s needs, looks and feels excellent, and is built like the proverbial tank. Besides, people seem to be hell-bent on pure sonic differences. I sure would prefer, say, a nice-looking Accuphase amp to a nondescript black box that technically does exactly the same. (Of course if it weren’t visible in the first place, the nondescript black box would do the job just fine.)
Cables are particularly problematic – let’s be honest, there’s not that much to an audio cable. First of all you need the right kind of topology (usually unbalanced for us), the cable itself needs to perform well (which for coax usually means good shielding and not breaking the capacitance record, especially if it gets lengthy), and you want some mechanically and electrically solid connectors (so maybe not the el cheapo quick-tarnishing variant). And that’s about it. No rocket science involved.
Of course there are several kinds of “special needs” cables with extra requirements, like ones you want to use for phono MM (total capacitance should be known and specified then), or headphone cables (these need to be thin and light without becoming too fragile or getting too much resistance). But that’s quite doable, too.
Read coverage of the whole debacle by someone with no skin in the game (meaning not JREF, not Pear Audio, not Fremer, not anyone audiophile affiliated). Gizmodo’s coverage stands out in my mind a pretty balanced. http://gizmodo.com/315250/pear-cable-chickens-out-of-1000000-challenge-we-search-for-answers All the parties involved displayed poor interpersonal skills, I’ll grant that.
copper is copper. silver is silver. there is no magic in rca jacks. inductance has very little to do or any at all to a cables performance especially involving impedance. it’s the resistance that matters most but that resistance is determined by the length your presenting. longer the wire,thicker the gauge you need. i know lot of people gonna hate me for this but there is no such thing as an ”audiophile cable” and never will be. it’s all marketing used to make sells. they all use the same copper. the same silver. only difference is the marketing,gauge used and how fancy it looks on the outside. it’s not magic or not rocket science. just common sense really.
RCA is a connector.
Cable is cable. There is no analog or digital cable.
The signal going through a cable can be anything. In the case of RCA, both. It depends entirely on the connection/interface.
That’s not entirely true since cables can be designed to different specifications. Some specifications work better for digital transmissions and some work better for analog transmissions…and some connectors are only ever used for digital transmissions even if it is technically possible to send analog signals through them (USB or HDMI being examples, though DVI is stupid and therefore doesn’t count…and I guess by definition that also makes HDMI stupid so I guess that one isn’t a very good example either).
So while an RCA connector itself doesn’t care what goes through it, there are technically digital and analog cables, although the only “true” digital cables are those that are built to a certain spec (USB is the best example).
Currently there is no evidence to support the idea that cables make an audible difference.
So I cannot understand why this argument continues
Are people really that stubborn, ignorant and arrogant that they will argue for something that they can provide no evidence for.
There is loads of evidence showing that cables do not make a difference and people can pick holes in this all they want, but they still have no evidence to support their claims.
More evidence that interconnects make no difference. A test of various Monster cables, with one from Radio Shack and one from Tandy thrown in, conducted by a Robert A Cooper at MIT for a Batchelor of Science in Electrical Science and Engineering and Masters in Electrical Engineering and Computer Science in 1998.
http://dspace.mit.edu/bitstream/handle/1721.1/46225/41567257.pdf
The conclusion is that measurements failed to find anything which could account for sound quality differences. There is a faint possiblity with noise and THD+N, but there is no correlation with that and any cables price or construction, so there is no reason to buy any one cable over another.
Regarding the idea that THD might have something to do with it, they briefly mention this, but go on to elaborate that for that level of distortion to be audible, you would have to be listening at 120db peak level (ouch) in an anechoic chamber – and even then it is unlikely to be audible, as it would be masked by the music.
One thing that is clear form threads like this is that there is evidence out there, but those who say cables do make a difference are never interested in finding any of that evidence at all.
That’s because their own experience is evidence enough for them. I’d say that much is pretty clear too. Again, that is the clear distinction between true “scientists” and “non-scientists,” or so to speak.
And behind that is the core belief of the subjectivists that their senses are more reliable than machinery, if not infallible, and that they show things which are not shown by the aforementioned machinery.
How anyone can hold this core tenet and support an entire belief system upon it, in the face of giant technological advances in measuring capability that have been with us for a rather long time now and overwhelming evidence, is beyond me.
Well, there’s also the rather overwhelmingly clear fact that our senses can be very easily deceived, especially by those who are trying to deceive us (i.e. the guys selling you the cables). People seem to overlook this quite often.
On the other hand, machines cannot be deceived so easily, especially under controlled conditions (not so much under uncontrolled conditions, however).
It is not the machines being deceived, it is people. Machines only do what it is designed to do. Any kind of error is human error, machines don’t make mistakes. Humans have limited senses. We can only see or hear only part of the spectrum. Our senses are not capable of providing accurate measurements given that bias nature of people, limited memory capability to replicate precisely what happened, and the different makeup of the each individual’s physiology.
I guess you’re right, what I really meant was that the machine could be “tricked” into giving the wrong answer if the test parameters are not strict enough. But it would in the end be human error causing the mistake, unless the machine itself is defective – which would most likely be human error, unless, say, a random cosmic ray went and messed around with your electronics.
Cable makers cannot influence a machine like they can a prospective buyer.
True. That’s what marketing does, it plays with the emotional nature of people. Marketers know to go for people subjectivity’s than providing objective results because subjective aspects cannot be proven, and adds emotional characteristics to it, it will grab people’s attention.
My analogy are the noises that water pipes are always making. sometimes quite and sometimes hissing, gurgling and sometimes banging.
We are listening to the flow of electricity through metallic pipes. It makes perfect sense to me that there are imperfections in that flow that are audible and that creative people with a good ear can craft better cables.
And yes your ears in this case are the highest resolution testing devices. What would you have to measure for, to look at a computer read out to tell you of the image depth, sound stage width, clarity of bass, mids and trebles. In a constantly moving and complicated structure such as music.
It is extraordinary that anyone could be trained to the level of belief that machines must be the ultimate tool, and humans must be second best.
Top Ace said:
And yes your ears in this case are the highest resolution testing devices. What would you have to measure for, to look at a computer read out to tell you of the image depth, sound stage width, clarity of bass, mids and trebles. In a constantly moving and complicated structure such as music.
It is extraordinary that anyone could be trained to the level of belief that machines must be the ultimate tool, and humans must be second best.
The sound has only two properties which can change over time. It’s frequency(ies) and amplitude(s). The way these two properties change over time can be measured, how you interpret the changes of these two parameters (“image depth”, “clarity of bass” etc.) are an entirely different subject and these are not the “real” properties of the sound, they are just the consequences of how the sound’s paramters change over time and how you try to interpret these changes in a way that makes sense. For example, when an istrument plays, you don’t hear the actual individual sine waves, instead you hear a “timbre”.
Once the sound gets converted to digital format, you can measure the properties of the sound nearly perfectly but definitely to a far greater accuracy then by your ears at the very least.
If you want to know if someone sounds good to you, your ultimate tool is your ears (not due to its “high resoulution” mind you). If you want to measure the sound (and don’t care much about how that sound is going to sound to you) machines are indeed the ultimate tool.
Exactly! Measurement is only about measuring differences, it’s not about the human interpretation of the goodness of those differences.
What I don’t understand is why people spend so much time arguing about stuff like this.
There’s all these sound science forums created for the sake of arguing in circles. And generally it’s the same 4 or 5 people in every thread.
I know that I didn’t set out to join a headphone forum to spend countless hours demanding science and proof. Makes me wonder if these people actually care about the music , or just actually hate life or themselves.
If someone wants to pay 10k for some cables , so be it. Would i? No. But I’m certainly not going to challenge every person on this site, and tell them their brain is fried and require evidence of their opinion on what they’re hearing.
electrical devices rely on proper science. electrical laws have been established and happen to work very well in practice, so we can do without your instinctive philosophy to solve the non existent mystery of audio cables. let’s not pretend to reinvent the wheel here please.
as for humans being superior to measurement tools, as a tool our ears’ sensitivity crumbles at such a rate that we came up with a logarithmic scale to represent it. at different loudness we perceive different frequency responses. the range of sound pressure and the range of frequencies we can hear is fixed and degrades as we age.
on the other hand you make this uninformed argument to talk about RCA cables. there isn’t even a need to use a tool as limited as a microphone here, we can directly measure with an electronic device straight at the output of the cable and get measurements magnitudes better than anything a human ear could hope to do.
and I won’t even start on psychology, bias, placebo, or the fact that you apparently can’t tell subjective interpretations from actual audio variables.
listening to music will always be the most important part of enjoying music. but jumping from that to thinking that your ears are better than proper measurements to tell reliably if something factually changed in the signal coming out of a cable, well that’s just very wrong.
Just imagine what life would be like if we were all audiophiles: No Hubble space telescope, humans can see better than any machine, no electron microscopes, CAT or MRI scans, no Large hadron Collider, etc. We’d save countless billions of tax payers money! What’s truly extraordinary is that anyone born in the couple of centuries or so can lack the education and be so fooled by marketing to think they are superior measurement devices to “machines”, something even the ancient Romans knew! And, if that’s not extraordinary enough, for anyone to publicise such a complete lack of basic science education in a forum dedicated to science is utterly mind boggling!
Makes me wonder if these people actually care about the music , or just actually hate life or themselves.
Makes me wonder that too! I’ve come to the conclusion that many audiophiles don’t care at all about the music, just their audio equipment. That’s a real shame for those of us who do actually care about the music because of all the resources being poured into snake oil to fool the audiophiles instead of spending it on improving the music (it’s creation, recording production and reproduction). Anyone who truly does care about the music therefore needs to speak up or they’re just lying and/or paying lip-service to really caring about music!!
I agree with your response to my quote. I’m by no means an “audiophile”, and don’t believe the hype with the audio industry.
But don’t you get bored , constantly trying to correct someone else’s beliefs or opinions? Just seems like a waste of time constantly debating in circles. Yes, I do believe that snake oil runs rampant, but you know that and many others in the science forums. I’m in it for the listening experience. Others may be in it for the gear. To each there own.
Guidostrunk said:
Yes, I do believe that snake oil runs rampant, but you know that and many others in the science forums. I’m in it for the listening experience. Others may be in it for the gear. To each there own.
If someone is into it for the listening experience we owe it to them to debunk the mythology and improve his experience. This can happen by appropriating funds used for improvement to areas where the improvements are actually audible, but only of those areas are known. Others are into it for the luxury gear, and there’s no changing that, but they are relatively few because that strata demands a higher level of net disposable funds. “A fool and his money are soon parted” (a quote which I found out originated in the late 1500s!). But if that fool has money he can afford to part with, then I guess I don’t care much.
RCA cable can improve the sound? IMO yes!
If someone thing the cable didnt help or change the sq, what is he/his basis ?
Sound is combine of tones from 15Hz to something higher than 20Khz.
Electrical characstics of them vary from frequency to frequency : RLC (resitor, inductor, capacitor).
RCA cable has those RLC.
One more thing is AC current runs differently base on frequency. Higher freq will tend to run on surface, while a DC current will run all cross section.
So a big single core wire is not good compare to a combination of many tiny cores.
Atleast we have some reason to comfirm bad rca and good rca.
Money is other story.
Oh dear. So many out of context statements and errors in the above post.
Money is other story.
He got that right.
TYATYA said:
RCA cable can improve the sound? IMO yes!
1. If someone thing the cable didnt help or change the sq, what is he/his basis
2. Sound is combine of tones from 15Hz to something higher than 20Khz.
3. Electrical characstics of them vary from frequency to frequency : RLC (resitor, inductor, capacitor).
4. RCA cable has those RLC.
5.One more thing is AC current runs differently base on frequency. Higher freq will tend to run on surface, while a DC current will run all cross section.
6. So a big single core wire is not good compare to a combination of many tiny cores.
7. Atleast we have some reason to comfirm bad rca and good rca.
8. Money is other story.
1. Science and reality
2. You missed most of the audible spectrum which lies below 15kHz
3. Resistors do not vary their value significantly at all with frequency
4. Very little L, very little C, like under 20pf/ft, and very low R depending on wire size and length. The only possible interaction is C with a high driving impedance, and length over 20ft.
5. Skin effect only becomes an audio modifier when the total change in impedance it causes along with the load creates a variation in frequency response in the audio band. This doesn’t happen with RCA interconnects because the wire size is too small relative that the total skin area, and the loads are very high impedance.
6. Depends on the load…see above.
7. Nope.
8. On that one I can agree.
Tomi Engdahl says:
Do RCA Cables Make A Difference? Lets Find Out !
https://stampsound.com/do-rca-cables-make-a-difference/
So, do RCA cables make a difference?
Premium RCA cables can make a difference, whether you hear it or not depends on your setup and expertise. Good RCA cables make a lot of difference for trained ears and a good sound system. On the other hand, using $10 RCA cables on a $1000 system would be unadvisable.
Indeed, you should even upgrade your power cable to avoid any unwanted electrical noises.
That was the short answer, but I went through a lot to be a premium-cable lover. Read on and find out everything about it.
What Makes A Better Cable?
What makes a cable better than another cable? Well, many items can fall into this category. Let’s take a closer look.
· Isolation – Cables’ isolation is what prevents them from picking up external noises. In cables like RCA, the more shielding they have or the better the isolation technique used, the more it will reject noise, thus your audio will be cleaner.
· Connectivity – The tips of the cable, the ones that make the connection with your audio equipment’s output an input make a huge difference. Some materials are more conducive than others. For example, gold-plated connectors are always better (as a rule of thumb).
· Strength – The strength of the signal traveling through a cable is mostly decided by the number of copper strands transporting it. The fewer they are, the weaker the connection and vice versa.
The list could go on indefinitely, but with those three items, you have more than enough info to get started.
Let´s Talk Sound Degradation
Let me introduce you to the villain in this story: sound degradation.
When we carry sound through cables, what we are truly carrying is voltage. This voltage reaches the speaker and, with the positive and negative loads, moves it to generate the sound. If the voltage would reach the speaker unmodified, the speaker would be able to translate into sound the exact, unmodified audio coming from the source.
Distances
The longer a cable runs, the more chances are that it gets sound degradation not only because of the distance but also because of the noise it can pick up on the way there. If you are using RCA cables that have braided shielding and OFMC construction (OFMC stands for Oxygen-Free Multi-stranded Copper), you’ll be able to reject noise and keep conductivity fresh throughout the entire length.
RCA Cable Noise
Noise can happen in short cables too, depending on how good the cable can reject it and how close it is to noise sources.
For example, I had an evening of hell in the studio trying to get rid of noise in the signal. I couldn’t find the problem until I saw very clearly how my RCA cable was sitting on top of the Wi-Fi modem. Network connections regarding data and Wi-Fi are a huge noise source. If you have good RCA cables you can fight back, but the best advice is to run them as far away from those as you can.
Grounding
Finally, grounding is something that is always going to affect your noise levels and thus the resulting sound. You need to have grounding for the electrical system before even thinking about investing in audio. The amount of noise a poorly-grounded electrical socket will bring to your state-of-the-art equipment is immense. The grounding comes first, always.
The Miscellaneous Matter Too
Some things make a cable better than others that are not strictly related to the connectivity or shielding, but with endurance. Buying good-quality cables is also to buy cables that will last you for a long time.
If you are going to be using your RCA cables in a spot in which they are going to be moving a lot, you need highly-durable cables.
Conclusion: Mind The Chain
The more we go into the audiophile world, the more we need to think of sound as a system.
Upgrading an already great system is more difficult and expensive than upgrading a basic system. The more you go up the audiophile ladder, the more expensive equipment you’ll find to make smaller differences. This is simply because, in the quest for pure sound, you need to get rid of all that stands in the way.
Tomi Engdahl says:
https://www.diyaudio.com/forums/parts/285128-measuring-capacitance-rca-cables.html
https://www.audiosciencereview.com/forum/index.php?threads/any-technical-minds-know-about-cable-capacitance.18550/
lack the technical knowledge to dig into the argument made that I will post below, but I was wondering if anybody who is technically adept could tell me if the arguments being trotted out by a cable believer is pure bunk which I suspect it is. Essentially this person is stating that the capacitance of audio cables can and will have audible effects. Specifically the poster on head-fi stated:
START —–>
Its not baseless at all. Capacitors are low-pass filters.
A high output impedance or using a passive preamp, followed by a high capacitance cable, will cause treble rolloff. This is not snake-oil, this is fairly basic EE.
You can see the measured effect here: https://www.superbestaudiofriends.o…uator-comparison-technical-measurements.7324/
Manufacturers of passive preamps will warn you of this too: https://tortugaaudio.com/what-is-a-passive-preamplifier/
And the audible effect? Well, try it for yourself. If you can’t hear a several dB rolloff by 20khz then I don’t know what to say.
Unless a ‘passive preamp’ has a step-up transformer, call it what it is. An attenuator, impedance matcher or switch box. It is not signal amplifier unless it goes into resonance.
Output impedance + cable capacitance makes low pass filter, not high pass. The equation is
F(-3dB) = 1/(2*3.14*Rout*Ccable)
Thank you everyone for chiming in. The head-fi poster was suggesting that keeping your interconnects as short as possible would matter audibly due to capacitance. I was suggesting that with normal length audio interconnects for home that there would be no audible effects due to the cable. Are people here saying that a run of the mill RCA interconnect that is 6 feet long may effect the sound audibly versus say a 2 foot length of the same cable?
For any reasonable coax RCA cable, a 2 foot cable and a 6 foot cable will sound the same. But a 50 foot cable may have more low frequency background noise than a 2 foot one.
With modern circuit design (low output impedance and high input impedance) the cable would have to be much longer than 50 feet before capacitance starts to matter. (with reasonable coax cables)
Most active preamps have an output impedance around 100 ohms to perhaps 1 k-ohms, with some tube preamps higher. Typical coaxial interconnects have capacitance around 20~30 pF/foot.
Treating the cable as a lumped capacitance (not quite correct but good enough for this particular debate), and ignoring the cable resistance as much, much lower the the preamp’s driving impedance, let’s target 25 kHz for -3 dB, use the 1 k-ohm output, ignore the load (amp input — it will extend the bandwidth a little), and choose 30 pF/ft for cables for a worst-case analysis:
Corner (-3 dB) frequency fc = 1 / (2*pi*R*C) so C = 1 / (2*pi*R*fc) = 1 / (2*3.14159*1000*25000) = 6.366 nF
Now c’ = 30 pF/ft for the cable and so the length L of cable you can tolerate in this example is L = 6.366e-9 / 30e-12 = 212.2 feet.
If your preamp has 100-ohm output impedance you can tolerate 2122 feet.
Yes, it is a low-pass filter, but unless your room is exceptionally large it will not be a problem for you.
I am pretty sure this calculation has been done many, many times before on ASR and many other places.
If you are using a passive preamp (why?), then it is probably a potentiometer (variable resistor), and may be in the 10k-ohm to 100k-ohm range so indeed is a much higher resistance and will roll off much sooner. A good reason to not use one without a buffer. They will argue the buffer adds noise and distortion; true, but negligible. The most subjective “purists” always manage to ignore the gazillions of active devices in the recording path in their conclusion that their electronics must meet some completely unrealistic standard of excellence. The same folk who abhor room treatments, neglect speaker distortion, and disparage specifications as meaningless.
watchnerd said:
Capacitance is a legit concern with phono cables used with MM cartridges.
True, but most cartridges are designed to work into typical cable capacitance and need a little extra in the preamp for a few (say 6′ or under) of cable. If the TT is far from the preamp, like across the room, you may need to place the preamp closer to the TT. I have seen that a few times (even in my own system) and had to do a bit of rearranging to accommodate that setup.
I skimmed pretty quickly and did not follow the links, but it sounds like the situation was with a “passive” preamp, which is more sensitive to cable (and all other) capacitance.
Speedskater said:
With modern circuit design (low output impedance and high input impedance) the cable would have to be much longer than 50 feet before capacitance starts to matter. (with reasonable coax cables)
Emphasis on modern circuit design. “Passive preamps” may not qualify. You can generally get by with a 10k pot but any higher than that, and worst-case output impedance tends to get uncomfortably high. Everything based on transformers also tends to be tricky business… it is essentially impossible to meet typical max capacitive loading specs of 10k:10k jobs with typical line-ins (recently I saw one that specified 50 to 100 pF max – input filter capacitance alone tends to be 100-220 pF at least, not even accounting for any cable runs).
watchnerd said:
Capacitance is a legit concern with phono cables used with MM cartridges.
Indeed. Notoriously inductive buggers whose impedance magnitude tends to reach the double-digit kOhms towards the upper end of the audible range.
I’d note that -3 db at 25 khz will sound sightly soft to younger years.
Really? They hear 25kHz with any amplitude? Even so, how much musical information is contained that high up and with appreciable amplitude?
It’s not a brick wall.
If it’s a first order slope, it will still be down a few dB <20kHz.
The point I was trying to make was that it takes a lot of cable with an active preamp before significant HF roll-off occurs. Feel free to provide an example that is more realistic; I just picked 25 kHz as a little above the audio band and didn't think through the curve.
Here's a plot for a single-pole (first-order) roll-off from 100 Hz to 30 kHz using a 25 kHz corner (-3 dB) frequency:
It is about -0.1 dB at 4 kHz. The highest I ever tested (in college) was around 22 kHz IIRC. Was not tested (or do not remember) before that, and now at 61 my hearing rolls off around 10 kHz or so.
Below is a post of some cable simulations from long ago (ca. 2014)… Reposted from another forum. These are for short lengths and do not include the case of a passive "preamp" with much higher effective driving impedance.
—
I decided to play around with interconnects just a little. Mathematically, that is!
First, I checked a number of preamp, amp, and AVR specs (tube and solid state, from Pioneer to Krell and Audio Research) and found a range of around 20 kohms to 100 kohms input resistance, and none of them specified capacitance. I thought about assuming a 1 MHz input bandwidth, but that was 500 to 1000 pF or so which seemed a little high, so I picked 100 pF. Output impedances of the preamps ranged from around 200 ohms to 500 ohms or so, and with 1 MHz bandwidth the output capacitance is about 3 pF.
I used a couple of interconnects: a pretty standard 75-ohm cable (RG-59; 20 m-ohm, 21 pF, 118 nH per foot), and a low-capacitance cable I have used in the past (RG-63; 93-ohm impedance, 20 m-ohm, 10 pF, 86.5 nH per foot). I used 3 foot and 6 foot lengths (roughly 1m and 2m) in my trials, and distributed the impedance over ten stages/foot for better accuracy (100 stages/foot made essentially no change). I suspect most cables will fall around this range.
In the figures below I used four source (preamp-out) resistances: 100, 200, 500, and 1000 ohms. This spans the range I found plus a bit. I found a range from 0.2 to 0.01 ohms/ft interconnect resistance made no change in the results (<0.1 %). I plotted the frequency response from 10 Hz to 1 MHz, and calculated the response at 20 kHz relative to 10 Hz. There is essentially no significant loss at 20 kHz for any of these tests. Solid lines show 75-ohm cables, and dashed 93-ohm (low-C). Note the vertical scale is only 0.1 dB/division.
As you can see, there is virtually no loss at 20 kHz for any trial (-0.003 dB worst-case). While there can (and probably are) special cases, to me this shows that, for relatively short runs of typical cable and normal preamp/amp designs, there is little likelihood of frequency response being an issue. This does not address shielding or the myriad second and higher order effects that may be present, of course. However, I thought folk might find this interesting
I've always thought passive preamp was bad terminology. I prefered passive volume control or attenuator. But pretty much everyone knows what you mean if you say passive preamp. And communication is the name of the game not super grammar. Passive preamp communicates so good enough.
I would like to mention something about amp "input capacitance". As you know, practically every power amplifier has an RC input low pass filter to protect the input from RFI and other HF mess. The usual values are 1kohm + 1nF. This creates a "hidden" input capacitance and the effect of this capacitance strongly depends on output impedance of the sound source.
Please let me show the "real world" example. I have taken my AURA D7A stepped attenuator
https://www.tnt-audio.com/accessories/aurad7a_e.html
which has 22 kohm total impedance. This makes the "worst case" 5.5 kohm output impedance when it is set to -6dB attenuation and driven from low impedance source. I have put the RC lowpass 1k+1nF behind the attenuator, used the short interconnects and measured frequency response at 0dB and -6dB settings. Below is the result:
One can see that though at 0dB setting the response is flat, at -6dB setting the frequency response is audibly affected and the main reason is the 5.5k output impedance of the attenuator affected by the RC 1k+1nF lowpass, so usual input circuit of power amplifiers.
Many of the responders so far clearly did not read the linked content that the op was asking about. The question isn't about interconnect capacitance under usual circumstances. It's about whether introducing a specific model passive attenuator, with a higher than usual resistance, can interact with the usual interconnect capacitance, and introduce a potentially audible rolloff in FR.
I have not personally double checked the math, but the reasoning presented by the linked content appears solid to me. It's analogous to the same deleterious effect we might see when introducing high series resistance cable as an interconnect (or somewhat related, loudspeaker cable).
If the cable length is 10 m, then yes, if 1 m, then no. I had hoped I gave very clear example with the 22k attenuator several posts here above.
https://www.superbestaudiofriends.org/index.php?threads/goldpoint-sa2x-nobsound-ns-05p-passive-attenuator-comparison-technical-measurements.7324/
Tomi Engdahl says:
https://www.diyaudio.com/forums/parts/285128-measuring-capacitance-rca-cables.html
I then measured the capacitance of all RCA cables that I had in my possession.
I started with regular/generic RCA cables that came bundled with some of my DVD and CD players. All those cables have a length of 3-6 feet and their capacitance measured from 300 to 600 pF. The best generic cable had a capacitance of 328 pF per meter, which is too high for my tastes.
Generic RCA cable (328 pF per meter):
generic-rca-1.jpg
After that, I turned my attention to some of the premium cables that I had lying around. Surprisingly, the relatively cheap, Monoprice-branded cables were not worse (and sometimes even better) than much more expensive, premium RCA cables.
Monoprice 1.5ft Premium RCA 22AWG Cable (92 pF per meter) (1.5ft Premium 2 RCA Plug/2 RCA Plug M/M 22AWG Cable – Black – Monoprice.com):
monoprice-premium-1.jpg
ATLONA Double Shielded Composite Video RCA Cable (78 pF per meter) (1M 3ft Atlona Composite Video RCA Cable TV DVD VCR Double Shielded Gold Plated | eBay):
atlona-double-shielded.jpg
kenable Pure OFC HQ 2 x RCA Phono Plugs (256 pF per meter) (Amazon.com: kenable Pure OFC HQ 2 x RCA Phono Plugs to Plugs Stereo Audio Cable Gold 1m (~3 feet): Electronics):
kenable Pure OFC.jpg
Acoustic Research Performance Series Component Video Cable (82 pF per meter) (Amazon.com: Acoustic Research Performance Series Component Video Cable: Computers & Accessories):
AcousticResearch.jpg
Unknown brand Component Video Cable (83 pF per meter):
unknown-component-video-cable.jpg
Finally, I measured the capacitance of a 1.5 feet RCA cable that I made myself out of Canare GS-6 guitar cable (Canare GS-6 Guitar Cable Per Foot – Black) and Rean RCA male plugs with gold contacts (Rean NYS373-0 RCA Male Plug with Gold Contacts – Black). Interestingly enough, although this DIY cable cost approximately $8 to make, it had a capacitance of over 140 pF per meter, thus failing to beat some of the cheaper cables in my possession.
DIY cable (147 pF per meter):
DIY-cable.jpg
Video cable should have an RF characteristic impedance of 75ohms, and will normally have solid PVC dielectric giving a velocity factor of 0.66. It should therefore have a capacitance of 66pF/m. Either it isn’t genuine video cable, or you have a measurement problem.
The low capacitance of cheapo RCA cable may be a sign of very poor shielding.
If your signal source is high impedance, there will be HF loss. If, as most pre amp and line source equipment, the output impedance is 2k or less, there will be no appreciable losses using high capacitance cabling. Most line level is quoted at 600R.
3dB point for 2k and say 1200pF is 24kHZ, way above the human hearing spectrum. This is for unbalanced cabling.
Older cables types like RG59, KX7, etc had solid PE dielectric. Newer ones generally have foam PE dielectric and a much reduced capacitance.
I have never seen (true) coaxial cables using PVC as a dielectric, only shielded cables.
Something like CT165, which is a good 75R satellite cable, manages 53pF/m, thanks to air spacing. Only 93R coax manages better, but it’s hard to find.
Cables with lower capacitance are probably only partially shielded and not really coax
Here are a few i measured before,
Belden 89259 .75m = 47pf
Cambridge Audio Silver Reference .75m = 52pf
Cambridge Audio Qunex 99% OFC .75m = 104pf
Multicore cables (i.e. non coax)
NavShips 2x24g dual core shielded silver plated 1m = 54pf
Canare L-2T2S dual core shielded 1m = 78pf
Van Damme XKE quad core shielded silver plated 1m = 88pf
Canare L-4E6S quad core shielded 1m = 160pf
Measurements were taken with a cheap ebay meter so i cant claim absolute accuracy, but as a point of reference the Belden 89259 specs are 17pF/Ft, which is 56.7pF/Meter so my measurement of 47pf for .75m means its in the right ball park.
why not just read the Belden, Alpha catalogs, tech specs?
Whitlock pointed out that in consumer audio RCA interconnect shield resistance should be as low as possible
Quote:
Originally Posted by jcx View Post
audio return signal current isn’t the only current in the unbalanced gnd/shield/return – chassis leakage, gnd loop current, some EMI
symmetry, 100% coverage, 360 degree shield-connector barrel termination all make differences – as commonly found in “video” RCA cable
Whitlock:
Quote:
“Exotic cables will not stop noise. Expensive cables, even if double or triple shielded, made of 100% unobtainium, and hand woven by virgins will have no significant effect on hum or buzz. Only the resistance of the grounded conductor can make a difference.’ If you have to use coax, Belden 8241F, with a low-resistance copper-braid shield, works well for audio and video.
from:
Washington June AES – SMPTE.org
http://www.belden.com/techdatas/metric/8241F.pdf
Quote:
Electrical Characteristics (Overall)
Nom. Characteristic Impedance:
Impedance (Ohm)
75
Nom. Inductance:
Inductance (μH/m)
0.29529
Nom. Capacitance Conductor to Shield:
Capacitance (pF/m)
56.7613
Nominal Velocity of Propagation:
VP (%)
78
Nominal Delay:
Delay (ns/m)
4.2653
Nom. Conductor DC Resistance:
DCR @ 20°C (Ohm/km)
49.215
Nominal Outer Shield DC Resistance:
DCR @ 20°C (Ohm/km)
8.5306
Originally Posted by mcandmar View Post
Here are a few i measured before,
Belden 89259 .75m = 47pf
Cambridge Audio Silver Reference .75m = 52pf
Cambridge Audio Qunex 99% OFC .75m = 104pf
Multicore cables (i.e. non coax)
NavShips 2x24g dual core shielded silver plated 1m = 54pf
Canare L-2T2S dual core shielded 1m = 78pf
Van Damme XKE quad core shielded silver plated 1m = 88pf
Canare L-4E6S quad core shielded 1m = 160pf
Measurements were taken with a cheap ebay meter so i cant claim absolute accuracy, but as a point of reference the Belden 89259 specs are 17pF/Ft, which is 56.7pF/Meter so my measurement of 47pf for .75m means its in the right ball park.
Quote:
Originally Posted by Elvee
Older cables types like RG59, KX7, etc had solid PE dielectric.
Yes, you are right. I don’t know why I said PVC when I knew that RF coax usually used polyethylene.
Quote:
Newer ones generally have foam PE dielectric and a much reduced capacitance.
Even air dielectric would be about 45pF/m. Anything less than this is not 75ohm cable.
I notice that the figures in the first post have now changed! The 25pF cable is now 83pF.
Some of these hand held meters use a bridge method and give strange results when measuring cables where only one “plate” (the shield) has strays to ground
Tomi Engdahl says:
How is RCA cable capacitance measured?
Remove the cart, then clip one probe of the meter to the outer shield of the rca, and the other to the center pin. Before you do this record any reading on the meter as this is the capacitance of the meter cables (some meters you can zero).
https://www.vinylengine.com/turntable_forum/viewtopic.php?t=48254
Tomi Engdahl says:
I like low capacitance for interconnects. It’s not the only parameter to consider, but in general – low capacitance for interconnects, low inductance for speaker cables.
Tomi Engdahl says:
https://www.stereonet.com/forums/topic/87682-rca-interconnects-capacitance-rookie-question/
49 pf/ft is high-ish, some interconnects have more, IIRC the wireworld eclipse cables are about 300pf for a 1meter interconnect, so about 80ish pf/ft. 49 per ft shouldnt be problematic for line level stuff, Does matter with Moving Magnet cartridges into phono stages. The blue jeans lc-1 cables are at the other end, very low capacitance 12.2 pf/ft
GS-6 has a typical capacitance for the type of cable that it is, namely a screened audio cable.
Capacitance is a function of the outside area of the inner conductor, the inside area of the outer conductor, the spacing between the conductors and the dialectric constant of the insulation.
The first three properties will be the same for ALL cables of the same physical dimensions regardless of brand, and dialectric constants for typical used insulations (PVC, PE and PTFE) of the same order as each other (PVC is the worst). Thinner inner insulation will lead to higher capacitance. Foamed insulation will lead to lower capacitance. However foamed insulation does not have mechanically integrity and introduces other problems, including potentially microphonics. Less than 100% screen coverage will give less capacitance, at the expense of lower noise immunity for the cable.
GS-6 is designed for EXTREMELY LOW microphonics and VERY HIGH noise immunity compared to other screened audio cables. That makes it particularly suitable for audiophile grade interconnects and for low level signals, especially moving magnet cartridges on turntable. GS-6 is very low loss (low resistance), making it even suitable for short loudspeaker cables, with all of the benefits of a coaxial cable.
Capacitance in a cable forms one leg of a low pass filter that attenuates high frequencies. The other factors are the source impedance (which is a function of the design of the audio source device, and the cable inductance (which for coax interconnects is very low and inconsequential for this application).
Canare GS-6 has a capacitance of 160pF per meter. A typical consumer audio source has an output impedance of 1,000 ohms or less (professional audio equipment is usually around 50 ohms). We can work out how many meters of cable would be required to attenuate from a corner frequency of, say, 200kHz by using a formula. This would mean that 100kHz is affected by less than 1dB, far enough above audio frequencies to disregard the affect on audio in the cable.
The formula for the corner frequency is fc=1 ÷ 2πRC. We set fc=200kHz, and R=1000. So by manipulating the formula we can calculate the amount of capacitance needed to roll off at 200kHz. 1/C=2πRfc, or C = 1 ÷ 2πRfc, = 1 / 2 x 3.1416 x 1,000 x 200,000 = ~.000,000,000,8 farads, or 800 picofarads. Therefore you can safely run 800pF ÷ 160pf per meter = 5 meters of GS-4 interconnects with typical domestic spec audio equipment, for a corner frequency of 200 kHz, which is about ten times higher than the audio band upper limit. (Someone please check my maths
)
If you have decent gear with 50 ohm output impedance, the length becomes 125 meters. In reality, you could double these lengths and not notice – it would make about 0.1dB difference at 20kHz.
Canare GS-6 was designed for use in extreme EMI environments – like performance spaces surrounded by megawatts of dimmed lighting – for very weak signals (guitar pickups similar in output to phono pickups) and not to be affected by handling noise (microphonics), yet still be very flexible and non-kinking. These make it absolutely ideal for audiophile applications, where cables typically run alongside a mess of electrical cables. Even better IMHO than the quite good REAN (Neutrik) RCAs are Canare’s own purpose made RCAPs for GS-6, which require special crimp tools to install. Crimp connections have superior screening, pull strength and long life due to the exclusion of oxygen in the crimp connection joins.
When a cable manufacturer wants lower capacitance it is generally achieved by using unshielded cables. Why anyone would want to listen to music contaminated with EMI, hum and buzz is beyond me, but lots of people do and lots of cable manufacturers make unscreened or poorly screened cables.
To answer the second part of you question, a competently designed amplifier will not be affected by the small amount of capacitance in a signal cable. Low capacitance might be important for low grade equipment and / or long cable runs, but it is generally inconsequential for most real world domestic situations with competently designed equipment.
There is one exception, which is moving magnet pickup cartridges. MM cartridges have relatively low output impedance of 400 – 1000 ohms, but being a signal generator based on a coil they have series inductance as well. This inductance interacts with the load capacitance ‘seen’ by the pickup, which is the combined capacitance of the tonearm wiring (~50pF), the interconnects (~100-200pF) and the input of the phono stage (~150 pF).
The combined effect of the MM’s ‘load’ capacitance and source inductance is a peak in the high frequencies with a roll-off above. You want to make sure this occurs above the audio range where it doesn’t mater so much. To achieve this, most cartridge manufacturers recommend an ideal range for the load capacitance that should not be exceeded.
In the example above, the total capacitance is in the range 300-350pF. That would be fine for almost all cartridges. If, however, you cartridge recommends a maximum capacitance load of, say, 250pF, then you will need to find interconnects that have only 50pF capacitance. They will mostly likely be short, made with foamed PE dialectric and have less than 100% screen cover, so then you need to hope you don’t get hum and buzz pickup…
Yes, GS-6 is a great cable for audiophile equipment, and is perfectly ‘safe’ (it will not alter the sound by filtering) in your setting, between your phono stage and power amplifier. You can safely use 20 meters of GS-6 or more based on the E-200′s specification.
The E-200′s input capacitance is not specified and I can’t find any site that has measured it. I would expect it to be around 100-150pF.
The Concept V2 will work just fine into higher load capacitance. Clearaudio’s own Smart Phono has an input capacitance of 150pF, and the Concept turntable’s wiring is 135pf.
Tomi Engdahl says:
Cables: RCA Interconnects
https://www.psaudio.com/copper/article/cables-rca-interconnects/
RCA Design Brief
RCA cable provides the most pristine electromagnetic properties possible due to a seemingly simplistic design.
1) Conductors
There is a lot of mystery around copper. The grains, or the molecular arrangement of the crystals
themselves, were recently found to not be what we thought.
The decision to use copper is based on several factors, none of which was price. Copper offers the best material for affordable cables, as well as a significant level of performance in superior electromagnetic designs. Far more expensive materials in lesser designs won’t work, and far more expensive materials in superior designs won’t work… for most of us anyway.
Copper is available in several process treatments and after-process treatments;:
Electrolytic tough pitch copper (ETPC)
Oxygen-free high thermal conductivity copper (OFHC)
Ultra-pure, Ohno continuous casting copper (UP-OCC). What is often called long-grain type
Cryo treatments. Used to improve copper’s physical properties only
Grain direction options. Music is AC. Which polarity would you like first, and at what frequency?
Belden offers the three fundamental copper grades; ETP, OF, and UP-OCC, as they sound different in the exact same electromagnetic R, L, and C referenced design. (Impendance, inductance, and capacitance.) We don’t know why they sound different, but they do. Belden does not offer options that cost more, but offer no benefits that I can hear as a designer. Sorry, but I’ve yet to hear cryo treatments (which are intended to improve the wire’s physical strength or grain direction) change the sound.
So why copper? It has a very low direct current resistance, a reasonably deep skin depth to manage current coherence, is pretty high in tensile strength for processing, and in most applications resists severe oxidation. The grain structure is clearly visible in form, but that alone is not what makes the different grades sound different. In fact, these traits from drawing the cable do not have as much effect on the sound as you would be led to believe. Belden’s manufacturing process allows the cable to be used in any direction, as the wires grains all go the same way.
Solid or stranded wire? This, at least, is easy. Solid wire wins every consideration. It is better suited to the way audio cable is used. It is cheaper. It is easier to process. It allows for better terminations. It has fewer of the gremlins that I call tertiary variables (stuff there isn’t a measurement or calculation for).
Conductor Size
So we’ve now chosen solid copper wire. The size of this wire sets the foundation, since the cable’s structure is supposed to allow a conductor to be as near zero R, L, and C measurement cable as we can design.
For the RCA cable, we want as small a wire as we can process as this will force the best current coherence through the wire, i.e. the same current magnitude at all frequencies. The exact skin depth calculation is a tool we use to gain the knowledge to reduce the wire size in audio cables. Skin depth is covered in more detail in Part 2 of the overview. [https://www.psaudio.com/article/cables-time-is-of-the-essence-part-2/]
RCA cables terminate into a theoretically infinite (47K-120K or there about) input resistor. When impedance is so high and current is so low, it is effectively an open circuit. The most logical solution is to use as low a diameter of wire as possible. However, a wire that’s too small can’t be reliably terminated, might permanently stretch too easily, and may break if there are any surface imperfections.
Calculations and testing resulted in the selection of a 0.0176” diameter wire for Belden ICONOCLAST. This is half the diameter necessary for an 18-mil skin depth at audio, so there is greatly improved current coherence. (Remember from the overview that skin depth is dependent on frequency. The smaller the wire, the larger the inner-current magnitude relative to the surface current.)
2) Dielectric material and geometry
How do we retain all that our carefully selected conductor can provide? That’s easy, just stick it in air and find an infinitely low ground potential for our unbalanced / single ended wire! Air is free, and by far the best dielectric to have, but packaging air with a cable isn’t as easy or cheap.
How do we use air as a dielectric? I take inspiration from semi-solid-core-dielectric radio-frequency cables. These partially suspend a wire in a tube with a spirally wrapped thread. However, tweaking the design to suit audio frequencies is difficult. The audio signal is very sensitive to the dielectric effects of the plastics near it, so the beading thread that maintains the air gap in the dielectric tube has to be carefully chosen.
So why Teflon? First, it has the lowest dielectric constant of any solid plastic. Its high tensile and elongation properties mean it is strong and durable in even thin walls, and allows the bead to stay round even under side-wall pressure. Maintaining the dimensions is critical, as there isn’t a lot of room to play with in this tube, since there is only one optimum asymptotic wire size based on a given tube inner diameter.
The ratio of the tube inner diameter (with an 80% air void) to the inner braid surface will determine the capacitance. Maximizing the air content will improve the efficiency of the dielectric so the smallest loop area for inductance will also yield the smallest measured capacitance.
As the wire gets bigger inside a given tube, it crowds out the air. We could drastically increase tube inner diameter and wire size, but we want to hold inductance and signal coherence in check. Inductance is the loop area between the wire and the inner braid, and that needs to be infinitely close, the opposite of capacitance. For a given tube size, we want the maximum air void, and the smallest possible wire-to-braid distance.
This means the conductor wire size has to be as small as you can process, with the desired capacitance. As the tube gets larger, capacitance will drop but inductance will rise, and the opposite with a smaller tube. The design target is 11.5 pF/foot on the bulk cable, and assembly capacitance would be 12.5 pF/foot.
Inductance isn’t as critical as current in high-impedance cables, in which current is effectively ride time limited by inductive reactance. This is near zero. In my listening test, cable with near zero on both L and C attributes sounded best, and a balance needs to be considered. The cable isn’t big or small; it is what it needs to be to work. The wire size we start with sets this all into motion.
3) Shield material and design considerations
We have a core tube and know the electricals. Now what? The braid.
This is much more important than people think, and for differing reasons than people think. No, it isn’t shielding. True, a double 90%+ braid has 90 dB RF shield properties but, I sure hope your equipment isn’t that sensitive to RF. Foils are much better and more economical for RF than a single 80% braid, and reach the 90 dB mark far more cheaply.
In all cases, there is that pesky thing called the shield between the ground points on every piece of RCA equipment you use. Though that shield wire should drain away stray current, it has resistance of its own, and that resistance creates a ground potential difference. This causes current to flow between the two end grounds, creating a voltage in the center wire of the cable. The hum you hear as a result is called SIN, Shield Induced Noise. We can reduce this resistance in the shield by using two 98% copper braids. This is expensive, but the right thing to do. The lower the braid direct-current resistance, the better the SIN rejection.
However, these braids will not shield magnetic interference. You need a low-permeability shield to block low frequency magnetic waves (anything below about 1 MHz starts to have a considerable effect on the electric field). If an RCA cable is to shield magnetic fields, the shield would allow a magnet to stick to it. This is an indicator that the material is “influencing” magnetic field flux lines, both into the metal and out in the air. We can manage the SIN noise with a good ground, but true extraneous magnetic noise is still tough to manage with unbalanced cables.
4) Jacket design and material considerations
The Belden ICONOCLAST uses a Fluorinated Ethylene Propylene (FEP) jacket, for good reason. FEP is the most chemically inert material there is, protecting your cables from chemicals, and UV-exposure through those nice picture windows in your house. Lesser plastic material isn’t as stable, or inherently flame-retardant. Nor can many materials be used in thinner walls.
Plasticizer migration out of the cable, especially near heat, is a real issue. A polyester or nylon carpet can take on the color of your cable laying on it! FEP does not have this issue, and will look nice for decades to come. Yes, it costs more
RCA Summary
Knowing that RCA cables aren’t as “shielded” at audio as we think, what can we do about that? If you don’t have an interference problem, you’re good to go! RCA is a great-sounding cable with good fundamental electromagnetic design. This is why it was created. It does have issues with magnetic noise immunity, though.
Tomi Engdahl says:
Is cable sound real? A more holistic approach trying to track it down.
https://www.audiosciencereview.com/forum/index.php?threads/is-cable-sound-real-a-more-holistic-approach-trying-to-track-it-down.19807/
Hi everyone,
We all know the myriads of testimonials about cable sound obtained from sighted listening and completely uncontrolled conditions (level matching etc), which makes them basically moot. Then again, the sheer number of reports would statistically allow for at least a handful of setups where some form of cable sound actually did happen and could have been proven with the right means at hand.
Generally, I’d like to divide potential cable sound — talking line level interconnects here as for now — in two categories:
Category A, trivial cable sound: this is what comes from using a cable simply not up to the task, and/or from side effects not actually contributed by the cable itself, apart from its basic properties. Some examples would be:
using a very long high capacitance cable on a very high impedance output (passive preamps and such).
using long unbalanced cables, or ones with high shield resistance, or even unshielded „return wire“ types in setups with „ground loop“ problems. Same with cables that have open shield connection on one end.
using badly shielded, or even unshielded cables in general picking up external electrical and magnetic fields, and notably in setups where the cable connects to devices that suffer from EMI problems (RF demodulation)
…
Category B, what I would like to coin „intrinsic“ cable sound. This refers to the claims that the construction of the cable is making a difference even when the simple lumped parameters relevant for interconnects — capacitance, inner conductor(s) and shield resistances — are about the same (if that even matters, that is). Some examples would be:
silver conductors sound different than copper conductors
high purity copper / silver conductors sound different than off-the-mill copper / silver
single-strand (solid-core) conductors sound different than multi-strand
plated conductors sound different than non-plated
isolation materials matter (dielectrica)
geometry details matter
…
We would only be interested in Category B here, the „intrinsic cable sound“ claims.
Attempts have already been made trying to verify cable sound in more controlled manners, like the required level-matched blind comparison, and occassionally some positive results may actually have been found. Alas, the setups usually were not prepared for a technical investigation, on-site and in-situ, as to what causes the differences, technically. More simply worded, it is a futile attempt to measure the cables under completely different conditions than those that applied during the blind tesing (assuming it created positive results). You might say when we are after intrinsic cable sound the circumstances should not matter much and the „characteristic“ of the cable should manifest in the lab, and of course this should be true. Then again, when a BT yields positive results wrt to differences percieved this sort of guarantees — within the limits of the statistical significance the test allows for — that there must be actual differences in the signal and it would be very nice and insightful to peel out these difference in the actual music material that was used for the test.
Cable Blind Tests in real life, using people’s actual HiFi rigs, are a complicated matter. But in this age and day of the internet, there is a way to remote the tests to a large group of participants by using loop-back recordings. While not exactly recreating the situation of a real cable change in one’s system, chances are there that the captured differences can still be identified. Plus we have the great opportunity that the circumstances are extremely well defined and replicable and everything is in one hand, allowing for meaningful analysis as the setup for the recordings is exactly the same for the technical investigation and the recording for the blind testing.
Important note: We all know this is a loaded topic, and with the majority of ASR members probably leaning to the objectivist side of things it is clear that many of us will be thinking like „c’mon, it’s already been proven in many measurements — like Amir’s — that proper cables make no technical difference for the transmitted signals whatsoever, so don’t waste your/our time on this“. If this is your stance which is completely viable of course, then please do NOT post in this thread (and any associated threads that might follow). I would like to encourage a meaningful discussion on technical and procedural details under the premise that it does actually make sense to try such an investigation as outlined above. Some of you also might participate in the more subjectivist forums and could gather some comments, or even actual participation, from the membership there, maybe acting as a man-in-the-middle to relay discussion and results of those who don’t want to register here.
I’ve personally been migrating from the “cables make a (subtle) difference” side to the “maybe cables don’t make a difference if well engineered” side over the last year or so. Sounds like an interesting idea – I’d participate in the test.
I would like to propose a different approach. People say that silver cables sounds more open. Or brighter. Vs copper ones. More emphasis on the s of a singer for instance. Or some instruments. Have believers pick their own music sections where they swear the difference is audible. On these specific pieces one can do measurements an blind tests. A problem which can occur is the following. Volume correction. Because there are some measurements out there which have indeed measured small differences in certain frequency ranges which are nearing or in the audible domain. If this is true, when one would do a volume matching test of a specific music section, you are in fact matching the measurable volume difference to zero.
Very ambitious, and all on the up-and-up.
I think it makes sense for there to be sort of two parallel paths for answering the questions you’re wanting to answer. One path is the path you are taking. The other path would be a study to empirically determine the thresholds in cable reactance, by which a cable would or wouldn’t have an audible effect. Presently we do simple analyses on the reactance of a cable and show that the deviation in frequency response is so small that it couldn’t possibly be audible. But something more rigorous would be nice, where the effect of cable reactance is simulated in a very precise manner, in an experiment similar to yours, to definitively establish the thresholds for audibility. This might actually be easier to do than what you’re wanting to do, and it would be beneficial in a different sort of way. If it were done with appropriate care such that the results were broadly accepted and stood up to criticism, then it would be easy and straightforward to demonstrate that a given inexpensive cable does not sound inferior to a more expensive cable that likewise has reactance within the bounds established as inaudible. The only way that anyone would then be able to claim that their weight-in-platinum cables sound different from ordinary weight-in-aluminum cables is if the reactance of their weight-in-platinum cable exceeds the threshold of audibility, in which case the reason it sounds different is that it alters the sound whereas the weight-in-aluminum cable does not.
This kind of testing might convince someone who is new to the audio hobby and on the fence.
But cable believers are generally a lost cause. They have to somehow come to an ideological paradigm shift on their own before they are going to change their minds.
It will be a lot of work with not much output. I tried a test with 10 m of balanced cable in the past. A lot of sighted impressions, no positive abx.
Klaus, how about injecting some interference current through the screen, as you already did once.
DAC–ADC loopback suitability will be argued upon for sure. Then again, in said german forum someone presented something close, the sound of cables attached to some MiniDSP SHD connected to an interface with an ADC, using different 5m XLR cables. The test was blinded (files not named according to the cables) and some said they heard a difference and interestingly they voted the seemingly higher quality cable (SommerCable KarboCab) sounding best, followed by a Vovox. The loser was a off-the-mill cable from Thomann. So there is some indication that recordings can actually reflect the actual use-case, confirmed by actual believers.
My intent is not trying to convince the believers that cables don’t matter, rather really want to help find cable sound of the non-trivial case with at least some scientific rigor and use the chance to measure something that might explain it — if it is there any, the blind test is the prerequisite for the investigation, and the sighted test ist prerequisite for the blind test. Now, if those pre-requisites fail this is also a set of data point that might help some to question their beliefs. When there is nothing heard, I sure could (and will) make measurements/analysis, too, and will likely find nothing there accordingly, but it will not prove the contrary.
Yep, this part of of planned further proceedings in case the original attempt utterly fails. There are many scenarios, RF also would be especially interesting, though much harder to do (and that would rely on an actual RFI sensitivity in the RME input stage, comprised of OPA1602 bipolars, so there is a chance it will unless RME did a really great job there. I’ve looked at the input stage on the PCB, no that much filtering I could spot immediately.
You might put the cables against the original file. As the people don’t succeed in original x tube preamp ABX, I strongly doubt they will get anything from different cables. You will get some sighted impressions (just impressions) and NO valid positive ABX result.
I’m so sorry to be a sour-puss, but I’m damned glad I’m out of all this bullshit long ago now. The cables I ‘*really* heard a repeatable difference with were all RCA single ended types (balanced connection removes a multitude of sins if done properly I discovered
) and the cables that ‘made a difference’ totally unsuited to audio use primarily. I do wish you well in this investigation though.
Here is the issue I have:
Even if one engineers cables to have a particular sound on purpose (yes, of course that’s possible with highly usual LCR factors), why the hell would you?
EQing your system via cables is just incredibly inefficient and complicated when you can just….you know….use EQ.
Isn’t that just making the same point as the first one and thus the commonly accepted reason why we do ABX tests??
Yes, but that is the problem: we can know scientifically and objectively that two pieces of gear are the same and yet hear different, that’s the point. I believe that subjectivists seem to feel that everyone in here completely disregards the second part, yet I’d be worried that nobody on ASR submits to the DBT protocol when actually listening to anything
It should be a primary matter to understand what is actually differently perceived when sighted testing, not merely assess that people are biased. I guess it’d be very entertaining to somehow try to translate the difference in sighted testing into measurable features. Like, “person X percepts 2dB more treble when sighted testing on the same measuring amplifiers”.
SIY said:
Are you familiar with Pano’s potato and banana tests?
Yes I am, and made an Apple test myself. When it is hooked to a high input impedance amp (Tek AM502, DC bias applied through the apple) there was surprisingly little damage to the signal, but shielding the apple was a nightmare. With an 100k load (AP SYS2322 input) the degradation in level and distortion was quite high, though.
Original vs. loopback poses a problem for later analysis, the contribution of the DAC and ADC itself. To get a baseline, one would need to make also a shorted loopback test. Then we can just as well compare the shorted loopback vs. the cable loopback to minimize the unknowns and have better chances in the analysis, which will mostly based on subtraction techniques, looking into the residual, trying to remove the trivial linear stuff in the residual first to hopefully expose what really is interesting, some nonlinear effects, stochastic phenomena, whatever.
I think this would be incredibly hard to quantify down to the level of single digit dB values and specific Hz.
I usually hear things like “it sounds brighter” or “it has more detail”.
If the device in question is actually flat, I don’t know how you reverse engineer that perception into a specific perceived decibel value and frequency.
This is absolutely evident, however if people do not get original vs. tube (+inevitable DAC/ADC) with almost 3% THD, or signal recorded from power amp terminals loaded by speakers, then it is highly improbable they will get a cable “sound”. I know there is DAC/ADC added in the test I speak about and that I repeatedly prepared. Over the years of diyaudio tests and even here I became absolutely sceptical to disclose something like “cable sound” in online abx test, if it is properly prepared with matched level and time aligned. I know you will do it properly. But how can you expect to disclose anything in a properly prepared “cable test”???
You know why I used the test against the original? To shut the mouth to those arguing that the DAC/ADC path used was not good enough.
I’m not clear either.
OP, what is the specific question you’re trying to answer? It feels like you’ve come up with the experimental methodology first.
Right.
We already know:
–LCR values that are pathological in nature really can influence the sound, measurably so
–Sighted bias can influence what is heard, and the power of suggestion can influence specific perceptions (e.g. if you’re told silver cables sound brighter, you’re reasonably likely to hear it that way)
These are already well-established.
There may well be differences in cable sound, but if you have to do multiple run testing and then do a statistical analysis of the results to see if cable A really sounds better than cable B because the difference, if any, is on the fringe of audibility, then I have to wonder, is such a barely detectable improvement worth it? Seem like much ado about nearly nothing.
Wps998 said:
Hmm interesting and awesome effort..Whatever the results tho, i will still buy nice cables. I want to, i can afford them, my house has 3 phase power, my audioroom has dedicated 3 phase line, and buying cables does not make me sacrifice expense to my other audio gear. Buy what you want, what makes you happy and can afford. Its a hobby, there is no right and wrong, smart or stupid. If blingy things can cause bias and make you hear more, so can reading an article or chart can make you settle for what is not satisfaction. Enjoy it to the fullest.
Full ack. We must distinguish between the personal perceptual reality which, by definition, is real no matter what caused it, and hearing facts, which is what is left when any biasing is removed to best effort. Once we have established some hearing facts (within the limits of statistical significance), it starts to make sense to look hard for the reasons for it, which should be real differences in the signal as other causes have hopefully been ruled out.
Through different cables with slightly different lengths you will get identical data, if there is not some terrible flaw in the test set-up. And sorry, to test identical files one against another ……
So is the hypothesis that:
a) you will identify some phenomena that is reliably audible in DBT/ABX test that isn’t explainable by existing LCR models?
Or that:
b) all phenomena are expected to be quantifiable via existing LCR values and you’re just establishing a ‘threshold of audibility’ for skilled listeners?
a) would be an interesting breakthrough
b) is just quantifying something already known (skilled listeners can sometimes hear low level, but real, things normal people can’t)
Here is the issue I have:
Even if one engineers cables to have a particular sound on purpose (yes, of course that’s possible with highly usual LCR factors), why the hell would you?
EQing your system via cables is just incredibly inefficient and complicated when you can just….you know….use EQ.
That’s essentially the same point that I try to make about the idea of choosing an amplifier based on how you like the sound. Even if one intentionally engineers amplifiers to have a particular sound, why the hell would you? EQing your system via amplifiers is just incredibly inefficient and complicated when you can just…you know…use EQ.
Most of them still design amps and match parts by ear and use measurements as guide. Market for ‘colored ‘ sounding equipment is massive. Tubes, hybrids, turntables..not everybody likes or caters to ‘audibly transparent’.
egellings said:
There may well be differences in cable sound, but if you have to do multiple run testing and then do a statistical analysis of the results to see if cable A really sounds better than cable B because the difference, if any, is on the fringe of audibility, then I have to wonder, is such a barely detectable improvement worth it? Seem like much ado about nearly nothing.
Barely detectable improvement worth it (to you)? Those two words make the difference. Is buying a 10k omega to tell time worth it to you? This applies to every product category from shoes to TVs, furniture, handbags even mobile phone cases, its all the same. Serving the same function with made of similar material with intangible value proposition to the buyer. To prove or disprove fancy pretty cables is like disproving rolex does not keep time better than a tag, and a tag like wise to a lum tec and so on..comes back to personal taste and passion for a hobby. Completely subjective and intangible. And if you want to stick with 10 buck cables with 2/5/10K audio gear for the most logical and scientifically accurate reasons under the sun, all respect to you.
Just remember that the cardinal rule of statistics is “shit happens”. It’s common to use a significance value of p<0.05 for tests like these. A result like that is suggestive, but it also means that 1 time in 20 you will get such a result purely by chance. The key factor here is whether any positive results can be replicated.
It always annoys me when someone comes up with what looks like a positive result on a blind test (there have been a couple for amplifiers) and then touts this as a final answer that ‘proves’ subjectivists are right. No. All it does is indicate that there might be something worth looking at here. Getting a scientific result requires replicating the test, using a different setup to ensure that there isn’t any unforeseen factor confounding the result. Yes, it’s hard, too bad, science is hard. The significance level required for detecting the Higgs Boson was 5-sigma, p<0.0000003.
The most important thing is to ensure that replication is possible. Document everything, and try to ensure that the setup doesn't rely on factors that might be difficult or impossible to reproduce.
As several people have suggested, if this produces any positive result it will most likely be restricted to a subset of 'skilled' listeners who are sensitive to variations that pass most people by. So you really want to keep track of whoever is doing the tests and be able to invite people to do follow-up comparisons.
yes we need yet another cable tread on the internet as much a hole in the head .
"Is cable sound real? A more holistic approach trying to track it down."
Even the title is slightly biased ? try track what down now ? There is an built in assumption that there is something to track down or explore further that is not explained by simple basics as sane LCR values proper shielding and good mechanical design of connectors .
You can of course explore the endless hole of pathological high end design in both cables and the components themselves.
And find combinations that would surprise , but they are also explained by basic knowledge from 1930 .
It would be a good idea to include a ‘sanity check’. Obtain at least one cable that’s objectively, and audibly, inferior: highly inductive, or something like that. You could either fabricate this yourself or stare at one of Audioquest’s more expensive models for a couple of minutes so it breaks.
This will mean that the test contains at least one presentation that should elicit a positive discrimination and provide a baseline.
I used DeltaWave for some analysis a while back on a few balanced interconnects I had on hand. There were measurable null differences, although @ -100dB or lower:
https://www.audiosciencereview.com/…es-make-a-difference-a-null-test-result.7738/
DeltaWave has progressed since then, so now variable group delay and frequency response errors can be measured and corrected. I've just added a more perceptually-weighted metric to DeltaWave that should help with determining audibility of the difference. I would guess that anything with an RMS null of -100dB is extremely unlikely to be audible under normal listening conditions. Since my audio interface (Apogee Element24) isn't as low noise and distortion as the RME, it would be interesting to see your tests, and run the captures through the latest version of DW
Rather -50dB than -100dB. And effective dynamic range of the ear when listening to music sample is only about 30dB, which is moving up and down with average signal level, but instantly it is only about 30dB. There is no chance to hear any -100dB signal in presence of 0dB signal.
As a general note as I might have not been clear on that: I am personally 100% in the realist/objectivist camp. I don't believe in cable sound other than LCR-induced (pathological cases set aside), have neither experienced it nor measured anything substantial so far but I've also never used anything else than garden-variety cables myself. But my current personal stance is irrelevant here. 15 years ago I strongly denied impact of absolute polarity, and phase response in general, now I know better.
About 30 years ago I built a null tester.
Testing run of the mill cables (interlinks of about a meter length) and some higher priced (but not high-end) cables I found all the interlink cables I tested nulled perfectly.
So what went in came out. I cannot see how a boutique cable could do better than no change at all.
The only way would be if it became 'worse' but somehow 'sonic-ally preferred'.
For speaker cables things differ. Length and resistance mattered for nulling with real speaker loads (as expected)
Length becomes an issue when nulling. Due to speed differences phase shifted for the highest frequencies and as it was analog couldn't correct this.
Such phase differences result in amplitude differences which, without analysis of input and output signals can not be differentiated from upper treble roll-off. Digital this should be no problem (for Paul's software) I reckon.
KSTR Cable Test #01 (analog XLR loopback)
Hmmm ….. you do not want any comments in the test thread, understood.
They are either slight phase shifts due to different cable R-C AND/OR voltage induced into the loop with finite CMR diffamp elements. Interesting, however I am not sure how universal.
Phase shifts only or slightly different propagation delay. So the samples are in ns/10ns shifted.
Exactly. Plus an even more microscopic amplitude drop at HF for the higher capacitance cable.
Similar to this (not a measurement but a synthesized test case) : https://www.audiosciencereview.com/…-comparison-software.6633/page-23#post-649391
Contrary to popular belief, music signal is the least revealing of small differences in signal distortion and frequency response irregularities. For distortion, most revealing are pure sine tones and for changes in frequency response it is the noise signal, white noise.
I can see absolutely no reason for rising of the noise floor with the longer cable. The only difference I would admit would be that based on ground loop induction, that would reflect in changed mains spuriae.
UliBru said:
The top amplitudes show some small difference with a little more damping at high frequencies for the long cable = RLC parameters (for visualization the colors are switched):
View attachment 108973
So it seems possible to measure cable differences with quite different cables. For cables of same construction and length but e.g. different conductors (copper, coppy 5N, silver …) I expect much less differences.
At 1000 Hz we can see a 0.0155 dB difference between both cables.
At 20 Hz, the difference looks more like 0.016 dB
At 20 kHz, it looks like 0.017 dB
Which means that the long asymmetric cable has a frequency response of -0.005 dB @ 20 Hz and -0.015 dB @ 20 kHz.
I got the same results measuring the addition of a 5 meters standard asymmetric extension to a standard asymmetric interconnect : 0.01 dB of loss at 20 kHz.
"I'm sure you can get a difference in DiffMaker (the flac files should convert easily), the more interesting question is whether or not you can actually hear a difference. After all, if there's night and day audible differences between copper and silver or PVC and Teflon, you'd think that banana/potato vs copper or mud ought to be blatantly evident."
Tomi Engdahl says:
Fancy Interconnects? How about a potato, or even mud?
https://www.diyaudio.com/forums/everything-else/236248-fancy-interconnects-potato-mud-36.html
Tomi Engdahl says:
How do you know if your caps have aged?
https://www.youtube.com/watch?v=icTwm0RgFRA
Capacitors in electronics as well as loudspeaker crossover networks age. When and how do you know to change them to newer ones?
Tomi Engdahl says:
Audio grade inductors – Types used in speaker crossovers
https://audiojudgement.com/audio-grade-inductors-speaker-crossovers/
Inductor quality
Inductors are also called coils, for obvious reasons. So, when you are checking out some coils, if you want them to be audio grade inductors, check the following :
Coil core.
Wire used.
Manufacturing quality.
Types of audio grade inductors
You can image that there are quite a few types of inductors out there. But let’s keep this article to the point and focus only on the types which are most often used.
Iron/ferrite core inductors.
Air core inductors.
Foil coils or ribbon coils.
The order is not random. I list them in ascending order, from the sound quality perspective. This is also proportionate to price as well. You can expect that a foil coil is way more expensive than the equivalent iron core inductor. However, that does not mean that iron core coils doesn’t have their place. You can use them successfully in numerous projects.
Iron core inductor
The iron core is one of the cheapest audio grade inductors out there. While we like to call them iron core, the core can be made by various ferrous metals (not just iron). The core can have different shapes. As you can see in following image, one has a square core and the other a cylindrical one.
Since the core is metal, you don’t need that many windings to achieve the desired inductance. As a result. we get few benefits from this :
Less windings – cheaper price.
Lower DCR rating. This is a solid plus. High inductance coils can have a higher resistance rating, which is rarely a good thing.
A solid core provides support for the winding and minimizes the microphony effect.
Air core inductors
These types of inductors are the ones which are most widely spread in the hi-fi community. While they are more expensive than the iron-core counterpart, they are affordable if the inductance value doesn’t reach high levels.
Unlike the iron core, which has a solid metal in the middle, the air core has … air. And this is the ideal core material. Some have a piece of plastic for added rigidity. But the point is that it’s a nonconductive material. As a result, they are superior as far as accurate pulse reproduction and distortion numbers. These audio grade inductors can be used in any part of the crossover. However, since there is no metal core, the number of windings is larger, to reach the same inductance rating. This means (besides a higher price) that the resistance is higher.
Foil inductors
These are considered to be the best audio grade inductors out there. There is quite a bit to be said here, but the conclusion is short and straightforward. Do you have a big budget and want to go all out? Get these.
You can clearly see the difference. No wire here. Instead, a metal foil or ribbon is used. The foil is wider than a conventional wire. Also, because of its shape, they can be tightly packed. As a result, they have a large contact surface between the windings and create a high mechanical stability. If you compare the microphony effect of different types of inductors, the foil coil is miles ahead. It has the lowest measured vibration.
The foil coil is the closest to the physically ideal coil more than any other design. It excels when it comes to music dynamics, imaging and lowest distortions. There are people out there which will argue that there is no need to spend so much money on these. On the other end of the spectrum there are guys which can have nothing but the best.
Conclusion
Depending on you project, there is a spot for any type of inductor. When it comes to building crossovers and using audio grade inductors, I usually follow some simple guidelines. If budget is a priority use iron cores. You want to build hi-fi speakers and prefer to spend more on speakers drivers? Use air-cores, or use air-cores on the direct signal path and iron-cores for the rest. Going for an exotic project? Use film coils or a mix of air-cores with film coils. It all comes down to your budget. Because, sometimes, the differences are so subtle you find it hard to justify the extra cost.
Inductor Cores: Material and Shape Choices
https://www.mag-inc.com/Design/Design-Guides/Inductor-Cores-Material-and-Shape-Choices?gclid=EAIaIQobChMIp-Xd5P7s8wIVRhV7Ch10UwUmEAAYASAAEgJ4IPD_BwE
This article provides a comparison of Magnetics powder and ferrite cores when used in inductors, including small and large DC inductors and large AC inductors.
The physics of soft magnetic materials result in the case that commericially useful materials range from about 0.3T to 1.8T in Bsat.
The power inductor gap may be realized in one of two fashions, discrete or distributed. Distributed gap materials are powder cores. At a microscopic level, magnetic alloy powder grains are separated from one another by binder insulation or by high temperature insulation coating each grain. (This is not at the magnetic domain level; domains are vastly smaller than powder core grains.) Distributing the gap throughout the powder core structure serves two main purposes: (1) eliminating the disadvantages of a discrete gap structure, which are sharp saturation, fringing loss,and EMI, and (2) controlling eddy current losses so that higher Bsat alloys may be used at relatively high frequencies, despite comparatively low bulk resistivity in the alloy.
Discrete gaps are most commonly used in ferrite cores. The main performance advantage of ferrite is low AC core loss at high frequency, due to high material resistivity in the ceramic material, compared with metal alloys. Ferrites are at the low end of the available range for Bsat, and they shift down in Bsat significantly with increasing temperature. The discrete gap structure results in an inductor that reaches a sharp saturation point, requiring lots of headroom in the design. Discrete gaps also result in inductors that are vulnerable to eddy current losses in the coil due to fringing, and to generating EMI. Discrete gaps are also used in amorphous and nanocrystalline tape wound cut cores, which have improved AC loss performance compared with powder cores, but often at a cost disadvantage.
Conclusion
For a given inductor, the material selection decision is informed by constraints of: space; efficiency; assembly; winding; total cost; inductance vs. load characteristic; temperature rise; and temperature rating. Among powder cores, MPP material is superior for core loss properties, and has highest available permeability. High Flux has an advantage when space and DC bias performance are critical constraints. Kool Mμ is consistently a lower cost option than MPP or High Flux, and is offered standard in both toroids and E-core geometries. Iron powder grades are lower still in cost than Kool Mμ, but with significant tradeoffs in performance.
The inductor designer must meet the energy storage (inductance) requirement, as well as requirements for total loss, space, cost, EMI, fault-tolerance, temperature performance, and reliability. In the many cases powder cores have the clear advantage. Then the designer has a variety of options in choosing among the powder cores.
Tomi Engdahl says:
Do electrostatic speakers sound good?
Electrostatic speakers produce levels of distortion one to two orders of magnitude lower than conventional cone drivers in a box. Electrostatic speakers’ clarity is extraordinary. The big downside is high cost, but electrostatic speakers have been popular with audiophiles for many years.
https://www.cnet.com/tech/home-entertainment/electrostatic-speakers-a-very-different-way-to-make-sound/
Tomi Engdahl says:
ELECTROSTATIC LOUDSPEAKERS: HIGH END HIFI YOU CAN BUILD YOURSELF
https://hackaday.com/2016/08/03/electrostatic-loudspeakers-high-end-hifi-you-can-build-yourself/
DIY Electrostatic Loudspeakers
https://drmrehorst.blogspot.com/2018/10/diy-electrostatic-loudspeakers.html
Tomi Engdahl says:
Healing stones talk has some similarities to high end beliefs
https://hidastaelamaa.fi/2018/01/kivien-hoitavat-vaikutukset/#78552ae2
Tomi Engdahl says:
http://www.geofex.com/Article_Folders/carbon_comp/carboncomp.htm
The carbon composition (CC) resistor has been extolled as the paragon of pure tube tone by almost everyone who has a stake in vintage sounding amplifiers and effects. It’s reputed to be imbued with almost mystical powers to make toneless, lifeless guitar signals take on tonal advantages that only Zeus from Mount Olympus might achieve on his own.
Is this real? Are Carbon Comps really magic tone mojo?
Maybe. Like everything else, there’s the hype, and then there’s the real world. A good maxim to remember about electronics is that if you can’t express it in numbers (that are also measurable by someone else, not just made-up numbers… there are those around too
then you really don’t know the thing at all, you’re only believing the myth.
The vintage amps we all love had CC’s in them, and they certainly have their share of mojo, but the makers of those amps in the 50′s and 60′s used them because that’s what was available. Today we have lots of resistor options. What’s different about carbon comp, and can we express it in numbers so we don’t keep being superstitious?
Tomi Engdahl says:
http://www.geofex.com/Article_Folders/carbon_comp/carboncomp.htm
So I went to the internet and searched for manufacturer’s info on CC’s. The makers themselves admit that carbon comps have excess noise, high drift, high pulse power, and high variability. They also have a high voltage coefficient of resistance. Voltage coefficient of resistance?? What’s that?
That means that the resistance actually varies with the voltage across the resistor. The resistance is actually different if you put 100V across the resistance than if it’s got 0V across it. What that means to us is that if you put a 50V DC level across a CC resistor and a 100V sine wave superimposed on that, the sine wave will be measurably distorted by the resistor itself. We have resistor distortion.
The distortion is pretty much pure second harmonic. In small amounts, you can’t hear second harmonic as distortion, only a certain amount of “sweetening” or liquidity to the tone. That’s what carbon comp resistor mojo really is – the resistors are distorting, but in a way our ears like.
The manufacturers also document that CC’s have excess noise and bad drift with temperature and aging. That makes them a two-edged sword. Put everywhere in an amp, and they’ll both sweeten the tone, and at the same time induce hiss.
A little thought leads us to the following guidelines for using carbon comps for tone mojo:
1. high voltage across the resistor is necessary, in the range of 100V on up
2. large signal swings across the resistor are needed – ideally, a large fraction of the static DC voltage so you have signal swings of 50 to 100V too.
3. only positions in the amp that have both high DC voltage and wide signal swings as in 1 and 2 will give you enough resistor distortion to benefit from; other places should be chosen for low noise and/or economy.
4. resistor power rating should be the minimum needed to work for a reasonable life in the circuit to maximize resistor distortion. Maybe a good guideline is that the dissipation should be selected to be as close to two times the average dissipation as possible.
5. as a corollary to the power guideline, we should be prepared to replace CC’s every few years as the life at high temp makes them drift and get noisy(-er).
Guidelines 1 and 2 are simply the recognition that the voltage coefficient of resistance is not very big. In fact, although the coefficient is small, it was specified to be small by the makers and controlled tightly, indicating that it was a recognized problem. In the Radiotron Designer’s Handbook ( 4th edition, pg. 1345) they list the JAN-R-11 specification for CC resistors as less than 0.035% per volt for 1/4 and 1/2W resistors, and 0.02% per volt for higher power ratings. Given that the max voltages for these parts was 1/4W- 200V; 1/2W – 350V; 1W and 2W – 500V, that works out to a 7% change in resistance for a 1/4 W part used at its max voltage, a 12.3 % change for a 1/2W, and a 10% change for bigger resistors. That’s one of the thrusts of guideline 4 – pick the smallest dissipation resistor you can, to maximize the coefficient.
Of course, that’s as big as the effect can get, and you would have to carefully set up the situation to get that much resistor distortion. In an amp, you probably won’t be able to get that close to max voltages or signal levels. Realistic levels might be 200V across a 1/2W resistor, and a 75V signal swing. That would give you a 2.6% distortion – enough to be audible as sweetening. That’s the point of guideline 3 – you have to have a big enough signal swing across the resistor to have the signal distorted significantly by the voltage coefficient.
But with a 10V signal, you only get 0.35% distortion, and it starts down the slippery slope to inaudibility. More importantly, these percentages represent the maximum beyond which a resistor would have been rejected in the 1950′s. Today’s CC resistors are much lower distortion. From IRC’s web site, we find some numbers. A typical resistor voltage coefficient can be seen at http://www.irctt.com/pdf_files/IBT.pdf – which shows carbon comp at 0.005%/volt for that company’s products. Another was 0.008%/V. These are smaller than the max allowed under the JAN military spec.
Tomi Engdahl says:
For the same thing people will have different taste. There are endless possibilities.
If you are interested in this area of audio do the test yourself. Only you have your listening room, only you have your taste in what sounds right, only you have your ears and so on and so on.
One good way of testing anything is A/B switching it is instant and is not affected by any memories or thoughts your brain can throw into testing new things.
Test it for yourself!
Tomi Engdahl says:
“Possibly cables of different lengths might make some difference to whether they are bright.”
Longer cable has more capacitance which will attenuate high frequencies more than with shorter cable. Depends on source impedance if this is in any way significant or not.
What these people might be hearing is the difference in capacitance between half a meter & meter since the ideal cable is 63pF per meter apparently, so half a meter would be 31.5pF on a record player cable it could make a difference but maybe not at 1v line level elsewhere.
Tomi Engdahl says:
“When it can’t be measured it can’t be heard”
There needs to be a way to measure what is happening.
There are electrical measurements anf there are measurements that are done with proper listening experiments (A/B, ABX etc..).
If proper listening test reveals difference, but electrical measurements show difference, we need better electrical testing equipment/methods to understand that.
If there is electrically measurable difference but no difference in perceided sound quality, should we care of it or not?
If some person feels that there is sound quality difference when he/she sees the equipment, but on controlled “blind” testing does not notice differences, is there a real sound quality difference or just differend sound feeling due other things than actual sound quality?
Tomi Engdahl says:
Do optical audio cables eliminate noise?
https://www.youtube.com/watch?v=Z9bif7vZsmE
Optical cables have one big advantage: total isolation from their connected source. Does that mean their use is the best digital interconnect in a high-performance system?
Tomi Engdahl says:
Is there a national sound?
https://www.youtube.com/watch?v=i6rEnYbZpNM
Ever heard of the British Sound? How about the Japanese Sound? Paul clues us in on the various stereotypes for sound reproduction in the home.
Tomi Engdahl says:
Comments from https://www.youtube.com/watch?v=i6rEnYbZpNM discussion:
A lot of the sound comes from the room. US living rooms are huge compared to UK ones. Building materials are different too. Living in wooden houses v brick houses. Terraced v detached, having a lot of bass sounds great but depending on where you are living can make for angry neighbours, etc. I think the national sound is mostly compensating for living conditions.
I think the Brits like their bass, remember they have small rooms and they are solid brick in most cases construction what reinforces bass would sound awful how to balance if you had too much bass is just right for the size and material construction that is made from. you put this in a big room that is transparent material then you will lose the bass.
Answer me a question Paul…! somebody’s disagreeing with me how dare they lol feedback circuits, I said the feedback helps to lower the distortion figures and they say no it doesn’t which is right and doesn’t change how the sound it sounds only if it’s bad feedback design if such a thing?
In the academe, there is an interdiscipliary field of study known as “sound studies”. One of the areas in this is the exploration of “sound cultures”, where certain cultures are found to have particular ways of producing, interpreting, and/or preferring sounds. On the other hand in popular music recording, there are “sound signatures”. Western signatures used to be based on location, such as the dry New York sound, or the bright LA sound, or the expansive London sound. This has mostly disappeared since the 2000s due to globalization though, because many producers and/or engineers no longer stay put in one city. But cultural and industry differences still occur. For example, one can tell the difference between the sounds of a K-Pop and a J-Pop production of the same song, by the same artist(s), but released to different markets and in different languages.
I remember when most UK speakers were described as having a British sound and US speakers having either a West Coast or East Coast sound.
I guess manufacturers from different regions have somewhat similar regional philosophies with regards to sound reproduction. Maybe the Japanese uses their operas/traditional music as their “north star”, so they tune their sound to accurately reproduce that type of music as purely as they can. The English, maybe they look at European classical music. And the Americans, maybe look at Trap music. Lol. I kid, I kid!
now mostly in usa there is the fashion of the six pack subwoofers, exagerating bass. is that natural sounding? may be nice for movies but for music?? big subwoofer fans tend to exagerate bass and the final result is a big messy caricature of sound.
in general japanese and european audiophiles are more “educated” or purist.. no offense
I thought it would have been a “China sound”, seen as that’s where they’re all made.
I would bet money that there are more subwoofers per capita in the UK than the US by a considerable margin! All one has to do is listen to recordings mastered in different countries to hear the differences. UK masters definitely have more low end than US masters and Japanese masters have significantly less.
Two items:
1) I used to buy Japanese vinyl pressings. That is, until I found the same albums that were pressed in Europe and America, and I heard how much better they (the latter) were. To be clear, the better sounding pressings were hard to find. Even when you purchase from the right source, your odds are still not in your favor of getting a great sounding pressing. But your odds improve dramatically. So, for example, if I am seeking out the best sounding “Magical Mystery Tour” album, I know to not waste my time and my $$ with Japanese pressings.
None of my Japanese pressings can beat my best sounding British, German, and American pressings. So no more Japanese pressings for me.
2) A company that labels itself as a “high end” maker of audio products does not make them high end (does not make them “natural sounding”). What makes them high end (natural sounding) is what they ultimately end up producing. If it is built to last, and (most of all) sounds real, then it is high end. If you can hear the gear, then that (to me) is not high end (it is not natural sounding). It might be a very pleasing sound. But it that is not the same as sounding natural.
You should hear only the magic coming from your speakers. If a component makes its self known, if a component seeks attention, then that is not a high end component.
Studios, you would think, have high end equipment — and I suppose that some of their equipment is high end.
But studios screw up the vast majority of what they produce. So is it that their personnel funnel the sound through less-than-high-end gear? Or are the personnel incompetent?
Probably both.
I have heard of brands that are supposedly high end, and I have heard demos in stores of such equipment. Perhaps the store’s stereos were not properly set-up? But I would not own their gear if it were free. As soon as I hear an emphasis on anything, I deem that product as not natural sounding.
I am not going to name the brands, because I do not want any owners of those brands to be insulted — and I do not want to go back and forth with those folks in the comment’s section. But high end (or natural sounding) has to be heard to be considered natural sounding.
Tomi Engdahl says:
THEY’RE ASKING €214,- FOR THIS?!?!?
https://www.youtube.com/watch?v=M6O3YYKwxQs
INDEX:
00:00 – Intro
00:25 – What is P42?
00:44 – The sound of transformers
01:24 – A quick listen!
02:51 – The features and U.I
05:25 – Listening & testing
07:14 – Simulating a motown sound
09:55 – Conclusion
11:13 – Disclaimer
11:31 – Outro
Viewer comments:
The components have been emulated so precisely they’re even emulating the price of them
For a person that was building these things by hand in the 70′s and 80′s this is the biggest snake oil I ever saw. I remember how much effort we were putting into minimizing and compensating the magnetic field losses and hysteresis of the transformer ferro-magnetic core to NOT hear what this plug-in is doing.
You really disappoint me by not labeling this as snake oil.
Isn’t the point that people tried to minimize these artefacts, but by doing so the sound got too clinical and people have been wanting to go back to these imperfections?
the dev must have thought “make it super expensive, then people think it´s really good and worth it, that´s how apple does it”
but apple actually have good product proven by time, this developers have some product, one of many
If you look at this thing closely, it’s really nothing but a waveshaper and a few filters. All very digital, simple implementations, absolutely nothing special. It’s just that the parameter ranges are chosen well enough that most of its settings end up sounding reasonably analog enough. It all depends on the input though; feeding well already mixed soul-jazz-funk through it and using subtle settings it gonna sound authentic enough, but there’s absolutely no justification for paying for such basic DSP work. Hell, even at 10% the asking price it’d be too much, it’s barely worthwhile for free unless you just really like those parameter ranges and find them nice to work with.
Yes, most of the above exactly. Except it’s not a trig function of course, but a sigmoid, in specific just a tanh (hyperbolic tangent) based waveshaper. I’ve written my own waveshaper plugin (with lots of shaping functions that can be applied in series) that can do tanh waveshaping, and can null it with this plugin perfectly as long as the filters are off.
The filters themselves are nothing special either; they’re the usual cramping digital biquad filters derived from an analog prototype via either the bilinear transform, or approximated via trapezoid integration. Sadly they also seem to store the filter state in single instead of double precision based on the truncation artifacts in the output noise floor. Not necessarily an issue in practice, but if you boost the signal coming out of this a bunch you might start to hear some ugly low frequency “juddering” noise. At least the oversampling implementation seems to work properly, although it’s using a minimum phase antialiasing filter, which is not always ideal especially considering the plugin permits dry/wet mixing.
So no, there really doesn’t appear to be anything special in the implementation of this plugin, just extremely basic DSP code that could probably be done by using the bundled FX devices in your DAW or reimplemented by copying a few snippets from musicdsp.org. I don’t mean to disparage the site though, it’s a great resource for simple well understood DSP algorithms, but it’s quite misleading to put out a plugin that seems to be based on 20-30 year old algorithms and ask +200€ for it while claiming it’s an accurate transformer emulation. Especially the last part is quite a stretch for me, and they’d as minimum need to put out some actual technical details to justify this. Them marketing their product by saying a “world class math person” was involved rings quite hollow at the face of objective measurements.
I used PluginDoctor to look into the behavior of the plugin, you’re free to do the same. Let me know if this explanation is sufficient to back up my earlier comment.
For the price, I would expect automatic gain compensation and a usable GUI. That thing is not only ugly, it’s also clunky. Sounds pretty good, though.
i won’t pay this amount of money for a saturation plugin, but i gotta say that sound was delicious! i already liked your mix when it was clean but then you played around with the filters and the different ways to drive this thing and it suddenly sounded like it came directly from some iconic old film.
Their thought process must have been:
Ok, this is so specific only few people will buy this. So these few people need to make it worth it.
Tomi Engdahl says:
How I know that my MASTERING is GOOD?
https://www.youtube.com/watch?v=OdCiT52WtP8
INDEX:
00:00 – Intro
00:41 – I’m NEVER satisfied
01:31 – Speakers and Acoustics
02:40 – Ears
05:23 – Second pair of ears
06:57 – Technical Analysis
15:20 – Outro
A mix is never done, it’s surrendered
Tomi Engdahl says:
Normal People Try HIFI Headphones!
https://www.youtube.com/watch?v=EsoJacx1yTs
Tomi Engdahl says:
https://www.audiosciencereview.com/forum/index.php?threads/any-technical-minds-know-about-cable-capacitance.18550/
I lack the technical knowledge to dig into the argument made that I will post below, but I was wondering if anybody who is technically adept could tell me if the arguments being trotted out by a cable believer is pure bunk which I suspect it is. Essentially this person is stating that the capacitance of audio cables can and will have audible effects. Specifically the poster on head-fi stated:
START —–>
Its not baseless at all. Capacitors are low-pass filters.
A high output impedance or using a passive preamp, followed by a high capacitance cable, will cause treble rolloff. This is not snake-oil, this is fairly basic EE.
You can see the measured effect here: https://www.superbestaudiofriends.o…uator-comparison-technical-measurements.7324/
Manufacturers of passive preamps will warn you of this too: https://tortugaaudio.com/what-is-a-passive-preamplifier/
And the audible effect? Well, try it for yourself. If you can’t hear a several dB rolloff by 20khz then I don’t know what to say.
I’d note that -3 db at 25 khz will sound sightly soft to younger years.
Output impedance + cable capacitance makes low pass filter, not high pass. The equation is
F(-3dB) = 1/(2*3.14*Rout*Ccable)
Yes at some not unreasonable lengths and the wrong gear it can cause a mildly audible roll off.
Thank you everyone for chiming in. The head-fi poster was suggesting that keeping your interconnects as short as possible would matter audibly due to capacitance. I was suggesting that with normal length audio interconnects for home that there would be no audible effects due to the cable. Are people here saying that a run of the mill RCA interconnect that is 6 feet long may effect the sound audibly versus say a 2 foot length of the same cable?
For any reasonable coax RCA cable, a 2 foot cable and a 6 foot cable will sound the same. But a 50 foot cable may have more low frequency background noise than a 2 foot one.
With modern circuit design (low output impedance and high input impedance) the cable would have to be much longer than 50 feet before capacitance starts to matter. (with reasonable coax cables)
Most active preamps have an output impedance around 100 ohms to perhaps 1 k-ohms, with some tube preamps higher. Typical coaxial interconnects have capacitance around 20~30 pF/foot.
Treating the cable as a lumped capacitance (not quite correct but good enough for this particular debate), and ignoring the cable resistance as much, much lower the the preamp’s driving impedance, let’s target 25 kHz for -3 dB, use the 1 k-ohm output, ignore the load (amp input — it will extend the bandwidth a little), and choose 30 pF/ft for cables for a worst-case analysis:
Corner (-3 dB) frequency fc = 1 / (2*pi*R*C) so C = 1 / (2*pi*R*fc) = 1 / (2*3.14159*1000*25000) = 6.366 nF
Now c’ = 30 pF/ft for the cable and so the length L of cable you can tolerate in this example is L = 6.366e-9 / 30e-12 = 212.2 feet.
If your preamp has 100-ohm output impedance you can tolerate 2122 feet.
Yes, it is a low-pass filter, but unless your room is exceptionally large it will not be a problem for you.
I am pretty sure this calculation has been done many, many times before on ASR and many other places.
Essentially this person is stating that the capacitance of audio cables can and will have audible effects.
Capacitance is a legit concern with phono cables used with MM cartridges.
Capacitance is a legit concern with phono cables used with MM cartridges.
True, but most cartridges are designed to work into typical cable capacitance and need a little extra in the preamp for a few (say 6′ or under) of cable. If the TT is far from the preamp, like across the room, you may need to place the preamp closer to the TT. I have seen that a few times (even in my own system) and had to do a bit of rearranging to accommodate that setup.
I skimmed pretty quickly and did not follow the links, but it sounds like the situation was with a “passive” preamp, which is more sensitive to cable (and all other) capacitance.
With modern circuit design (low output impedance and high input impedance) the cable would have to be much longer than 50 feet before capacitance starts to matter. (with reasonable coax cables)
Emphasis on modern circuit design. “Passive preamps” may not qualify. You can generally get by with a 10k pot but any higher than that, and worst-case output impedance tends to get uncomfortably high. Everything based on transformers also tends to be tricky business… it is essentially impossible to meet typical max capacitive loading specs of 10k:10k jobs with typical line-ins (recently I saw one that specified 50 to 100 pF max – input filter capacitance alone tends to be 100-220 pF at least, not even accounting for any cable runs).
watchnerd said:
Capacitance is a legit concern with phono cables used with MM cartridges.
Indeed. Notoriously inductive buggers whose impedance magnitude tends to reach the double-digit kOhms towards the upper end of the audible range.
https://www.audiosciencereview.com/forum/index.php?threads/any-technical-minds-know-about-cable-capacitance.18550/page-2
As you can see, there is virtually no loss at 20 kHz for any trial (-0.003 dB worst-case). While there can (and probably are) special cases, to me this shows that, for relatively short runs of typical cable and normal preamp/amp designs, there is little likelihood of frequency response being an issue. This does not address shielding or the myriad second and higher order effects that may be present, of course. However, I thought folk might find this interesting.
I would like to mention something about amp “input capacitance”. As you know, practically every power amplifier has an RC input low pass filter to protect the input from RFI and other HF mess. The usual values are 1kohm + 1nF. This creates a “hidden” input capacitance and the effect of this capacitance strongly depends on output impedance of the sound source.
Many of the responders so far clearly did not read the linked content that the op was asking about. The question isn’t about interconnect capacitance under usual circumstances. It’s about whether introducing a specific model passive attenuator, with a higher than usual resistance, can interact with the usual interconnect capacitance, and introduce a potentially audible rolloff in FR.
If the cable length is 10 m, then yes, if 1 m, then no. I had hoped I gave very clear example with the 22k attenuator several posts here above.
Tomi Engdahl says:
https://www.audiosciencereview.com/forum/index.php?threads/my-thoughts-on-cable-design.24338/
At 60 Hz, the skin depth of a copper wire is about 8 mm. At 60 kHz, the skin depth of copper is about 0.254 mm. At 6 MHz, the skin depth is about 25.4 µm.
Electromagnetic shielding is common place and is used in signal and power cables. And will help to reduce EMC and RFI and is normally only useful from about 100KHz and above. It has little or no effect on magnetic interference as produced by electro mechanical devices such as motors, electromechanical transducers and transformers devices.
Magnetic shield using Metal shields for reducing radiated magnet field and magnet field susceptibility has been known about for many years and is used in many common place items.
A Magnetic shielded power cable will radiated about 80% less magnetic flux field than an unshielded power cable.
EWA have combine the EMC shield or Faraday cage with magnetic shielding to reduce radiated field and reduce the risk to the cable susceptibility to outside interference over a bigger bandwidth.
And by using a flexible magnetic materials make the cable much more useful than is presently available at the time of writing this document.
Faraday shielding as shown above will only work with radiated field and not magnetic shielding.
To calculate the size of the faraday shield material the material used could be copper, tin plated copper silver, silver plated copper or any good conductor.
Thus choice of the material depends on the whole environment conditions as with the insulation materials.
As can be seen the shield is woven braided conductor.
Coverage should not be lower than 85%, the angle of the braid should be 20° to 40° for a diameter of 15.2mm and up to and beyond 40°for diameter above 15.2mm.
Percentage coverage K can be calculated from the following
K= (2F-F2)*100
F=NPd/Sin a
A = Tan-1(2?(D+2d)P/C)
F= fill space, K=Percentage cover,N=Number of wires per carrier.P=pick/inch, d=dia of braid wire,a= angle of braid,D= dia of cable under shield, C=number of carriers.
Shield effectiveness is expressed in dB for a single shield of copper it is about 40dB at 85% coverage. And is about 45dB for 90% but using two layer of shield we can get as high as 60dB. And with the EWA interconnect cables we do this.
Magnetic shield of cables is good until it gets saturated. Then it is worse than no magnetic shield, because of the transformer coupling effect. (based on use of magnetic shield of coax cables in a high power testing lab)
It is not about “magnetic sources”, but about coupling from H and B field, in other words from the fields created by AC current flow. AFAIK even in studio racks power cords are sometimes placed in metal tubes and such metal tubes create magnetic shielding if made from iron alloy.
In studios, power cords are routed down the opposite side of the rack as the signal cables (Henry W. Ott – “Noise Reduction Techniques In Electronic Systems”, 1976, Bell Telephone Laboratories).
Correct me if I’m wrong, but aren’t ‘B and H fields’ and ‘AC current flow’ magnetic sources, or at least electro-magnetic sources?
In many installations metal conduit is used for both signal and AC supply, but this is old, established technology and has nothing to do with the bunk which is the topic of this thread. Engineers had this stuff figured out decades and decades ago.
Tomi Engdahl says:
https://www.audiosciencereview.com/forum/index.php?threads/is-cable-sound-real-a-more-holistic-approach-trying-to-track-it-down.19807/
Tomi Engdahl says:
https://www.audiosciencereview.com/forum/index.php?threads/mains-related-hum-and-noise-in-power-amplifiers.26645/