Here is a collection of interesting videos on microphones and microphone technologies:
Audio 101: Microphones
Dynamic vs Condenser Microphones, What’s the Difference?
Audio recording tutorial: The different microphone types | lynda.com
XLR vs USB Microphones, Which Should You Buy?
$22 MICROPHONE VS $3600 MICROPHONE | Andrew Huang
Voice-over Microphone || DIY or Buy
How a Neumann U87 microphone is manufactured
How to Make Your Own DIY U87 Vintage Condenser Mic
Soyuz Video #3 Capsules
The Soyuz SU-019 FET Microphone
MKH-416 counterfeit mic teardown
https://www.youtube.com/watch?v=Vdoeh7y0yeE
Disassembly – Taking apart the BM-100FX Microphone.
BEST Budget USB Microphone!? | FIFINE Honest Review
Why the Blue Yeti Sucks
Why the Blue Yeti Su cks | Pro Audio Engineer Responds
Do XLR to USB Cables Work?
Samson USB GO Mic Teardown
BM-800 Microphone Review / Teardown
Teardown of the Blue Yeti Microphone
Samson c01u usb microphone test + look inside
A quick teardown on the Samson Go Mic USB studio microphone for laptops and tablets
Samson C01U USB Mic Teardown (part of the article)
Random Teardown #001: Blue Snowball Ice Microphone
485 Comments
Tomi Engdahl says:
New VS Old Sennheiser MD421 Teardown – Big Differences! (Public)
https://www.youtube.com/watch?v=jHPQXqQ_2gE
Lets take a look at the differences between the MD421 vs MD421 II. There are vast differences and in many ways, not the same mic. Different capsule, different housing, different tuning methods, different everything except the look.
00:00 Intro
00:05 2 main versions
00:29 Fixing mics to pay the bills
02:00 Broken MD421′s
02:50 Compare the external differences
04:38 Ports vs no ports
04:52 How to open the mics
07:28 Removing the capsule
08:58 Comparing the housings
09:31 Internal ports and tuning
10:04 Removing the grills
13:08 Humbucking coils
14:31 Rear capsule vents
15:33 The mystery gear
16:05 Diaphragm and phase cover
18:12 Wiring
18:57 Bass roll off filter
20:15 Outro
Tomi Engdahl says:
MacGyver Style Testing – Speakers – Mics – Headphones (Public)
https://www.youtube.com/watch?v=f9sgxA6AhxI
I will show you how to test a speaker, mic, and headphones without using any test gear or anything powered. Don’t even need a battery!
00:00 Intro
00:28 9 volt battery test
01:10 Generating electricity with a speaker
01:47 Testing with a paperclip
02:15 Using a clip lead
03:20 Testing a compression driver
04:44 Testing a mic using a speaker
05:42 Use a speaker to test headphones
06:06 Test home hi-fi speaker with paperclip
07:00 Summary Outro
Tomi Engdahl says:
Open & Repair AKG C414 C451 Neumann U89 (Public)
https://www.youtube.com/watch?v=ZiuiWbt3jzU
A couple of broken mics from the Rat Shop so lets look inside and also check out a Neumann U89 while we are at it.
Tomi Engdahl says:
Hear Microphone Polar Pattern & Distance Level Drop (Public)
https://www.youtube.com/watch?v=KTdGhqz_WgQ
Here is a simple way to hear the microphone polar pattern and proximity level changes of microphones. These tests will give a great indication of how much gain before feedback and how sensitive a mic will be when singing close and far.
Check it out and let me know what ya think.
00:00 Intro
00:09 Simple gear, complex concepts
01:02 Polar patterns
02:20 Test setup
02:54 Calibrate levels
03:35 Hear om7 vs Beta58A polar pattern
06:07 Level drop vs distance om7 vs Beta 58A
07:10 Polar and level drop Beta58a vs Telefunken M80
08:30 Polar and level drop Beta58a vs SM58
09:17 Polar and level drop Beta58a vs Heil PR35
10:52 Polar and level drop Beta58a vs Royer 122 Ribbon
11:54 Null in polar pattern vs polarity
13:22 Outro
Tomi Engdahl says:
No One Cares About Your Audio Gear – Diminishing Returns on Microphones
https://www.youtube.com/watch?v=Z7-tnf0j0vs
Today I share my thoughts on diminishing returns and microphones, where the threshold his for dynamic mics and condenser mics, and what you might be getting for the higher price point.
00:00 – Intro
00:35 – Category 1: Dynamic Microphones
04:33 – Diminishing Returns on Dynamic Microphones
07:03 – Category B: Condenser Microphones
10:14 – Diminishing Returns on Condenser Microphoens
12:19 – Summary
15:04 – Conclusion
Tomi Engdahl says:
Open & Repair AKG C414 C451 Neumann U89 (Public)
https://www.youtube.com/watch?v=ZiuiWbt3jzU
A couple of broken mics from the Rat Shop so lets look inside and also check out a Neumann U89 while we are at it.
00:00 intro
00:20 AKG C414, C451E and Neumann U89
00:49 AKG C414 test
01:25 Parts box and replace
02:17 Open C414
03:25 Phantom powering
04:00 Test and open C451 capsule
04:40 C451 crackle sound
05:14 C451 Diaphragm
05:52 Reassemble C451 capsule
06:31 Disassemble C451 housing
07:05 Reassemble C451 housing and test
07:48 Open Neumann U89
09:00 Reassemble U89 and test
09:26 Outro
Tomi Engdahl says:
Mic Shootout – Neumann U67, Neumann U47, AKG C12, Telefunken ELA M 251
https://www.youtube.com/watch?v=weJD-ED7tRA
Really more of a mic match up, since there is not one mic that will fit every singer
0:00 U67
2:30 U47
5:00 C12
7:30 ELAM 251
Added a Ribbon Mic to the Mix. You can check that out at:
Mic Shootout – Ocean Way Audio RM1-B Ribbon Mic VS U67, U47, C12, ELA M 251
https://www.youtube.com/watch?v=j_my0pT7Sh0&t=0s
Tomi Engdahl says:
LAV’s LAW:
Anyone who needs a lav will show up wearing silk, satin, or shirtless.
“Phil Wallace 2022″
Tomi Engdahl says:
“Shotgun” Directional Microphone
https://cdn.preterhuman.net/texts/government_information/intelligence_and_espionage/homebrew.military.and.espionage.electronics/servv89pn0aj.sn.sourcedns.com/_gbpprorg/mil/shotgun/index.html
Tomi Engdahl says:
SM7B vs SM58 Mic SHOWDOWN
https://www.youtube.com/watch?v=FPO8dfE9inY
Timestamps
00:00 Intro
2:04 Technical differences with Dylan Lalonde
9:22 Sound comparisons with Aiden
Turn Your SM58 Into an SM7B!!
https://www.youtube.com/watch?v=rXPHGrR_JA8
The last time we tried this, we used EQ and compression to bridge the gap between the two mics.
This time we are actually actually making the SM58 as mechanically close to the SM7B as possible!
If you want to do this as well, it is super easy, but you are going to need a couple things.
Tomi Engdahl says:
Surely you can’t use an SM58 to record vocals…can you?
https://www.youtube.com/watch?v=cqqw_xVRsdY
The Shure SM58 is primarily known as an excellent live mic. But it can also be used for *recording* vocals in your home studio, despite what some people may say!
00:00 Intro
00:24 About the SM58
01:24 They say “Don’t use SM58 for recording vocals”…
02:01 Use the SM58!
03:16 Record now! You don’t need expensive equipment
04:59 Example of just doing it with cheap equipment
05:46 My EP made with SM58 for vocals
06:26 Get nervous recording vocals?
Why the SM58 is a great microphone for recording
https://homemusiccreator.com/sm58-great-mic-for-recording/
Tomi Engdahl says:
The Blumlein microphone technique PS
https://www.youtube.com/watch?v=0MBKe4Sz2fM
Allan Blumlein was the genius that invented stereo. How did he use microphones to build that first stereo system?
Tomi Engdahl says:
Vocal Mics Go Bad
https://www.youtube.com/watch?v=0gIrgXsioQE
Tomi Engdahl says:
https://www.homemade-circuits.com/diy-contact-mic-circuit/
https://www.codrey.com/electronics/piezo-ceramic-discs-practical-thoughts/
https://www.homemade-circuits.com/simplest-piezo-driver-circuit-explained/
Tomi Engdahl says:
http://www.learningaboutelectronics.com/Articles/Piezo-knock-sensor-circuit.php
Tomi Engdahl says:
Q. What difference do ‘free-field’ and ‘diffuse‑field’ capsules make to microphones?
https://www.soundonsound.com/sound-advice/q-what-difference-do-free-field-and-diffuse-field-capsules-make-microphones
My Brüel & Kjær 4006 mics have alternative black and silver capsules. The box says: “The black grid gives flat frequency response in a diffuse soundfield, the bright grid gives flat frequency response with 0 degree incidence in a free‑field.” What does this mean in practice? For the last 20 years I’ve been using the silver (bright) grid; under what conditions should I consider swapping them out?
SOS Technical Editor Hugh Robjohns replies: One aspect of omnidirectional mics, which surprisingly few seem to be aware of, is that they are fundamentally designed to be used either in the free‑field (which means close to the sound source) or the diffuse‑field, beyond the Critical Distance (where the direct and reverberated sounds are equal in level) in a reverberant space. Some omni mics can be reconfigured, either electrically or mechanically, to work in either condition, but most have a fixed characteristic and using the wrong one in the wrong situation will deliver a noticeably bright or dull sound.
So why is this capsule modification needed? Well, the frequency response of an omnidirectional mic is affected by where the sound source is relative to the diaphragm.
At low and mid frequencies, the wavelength is much larger than the diameter of the diaphragm, so the soundwaves simply diffract around the microphone as if it weren’t there. However, at high frequencies, where the wavelength is similar to the size of the diaphragm, some of the sound energy is reflected back into the incoming sound waves, creating a build‑up of pressure in front of the diaphragm. This acoustic interaction increases the microphone’s sensitivity to high frequencies, typically resulting in an HF boost of the order of 10dB at 16kHz (for a conventional small‑diaphragm omni mic) — it is quite a significant effect!
So the microphone designer faces a dilemma: should an omni microphone be designed to give a flat frequency response for close, direct, on‑axis free‑field sources, or for more distant, reverberant diffuse‑field situations? Both are valid recording applications for omni mics in different situations. In some cases, the dilemma is dealt with by including switchable electronic EQ, allowing the mic to be used in either situation. Since this is an acoustic problem, though, the solution B&K chose was an acoustic one: they designed different grids to sit in front of the diaphragm which correct the HF boost by controlling the pressure build‑up itself.
Tomi Engdahl says:
Current Loop Extends Wired Microphones Past 1 Km
https://hackaday.com/2022/09/27/current-loop-extends-wired-microphones-past-1-km/
A problem which beset early telephone engineers was that as the length of their lines increased, so did the distortion of whatever signal they wanted to transmit. This was corrected once they had gained an understanding of the capacitance and inductance of a long cable. The same effects hamper attempts to place microphones on long lines, and [Leo’s Bag of Tricks] has a solution for doing that using Cat5 cable. The application is audio surveillance, but we think the technique is useful enough to have application elsewhere.
Is Your House Bugged?
https://www.youtube.com/watch?v=YRWU80K8y30
Here we explore how a current loop microphone can provide audio surveillance at low cost and high fidelity.
Tomi Engdahl says:
Phantom Mic on a Mile of Cat5e Cable!
https://www.youtube.com/watch?v=f0nKK43Oeas
Lets listen to what Shure SM58 and a Neumann U89 sound like when run analog down a mile and a half of Cat5e cable.
Tomi Engdahl says:
A normal analog microphone can go OK through a kilometer of Cat5 cable. Audio “mythbuster” Dave Rat lets you to listen to what Shure SM58 and a Neumann U89 sound like when run analog down a mile and a half of Cat5e cable in tjhis video
https://www.youtube.com/watch?v=f0nKK43Oeas
Tomi Engdahl says:
Tips & Tricks – Repairing Mics: Shure KSM37 (137) Senn MD431, Audix i50
https://www.youtube.com/watch?v=BXuWosoTtSA
Broken mics came back from Coachella and from the Rat shop, Let’s dive in and do some mic repairs!
Tomi Engdahl says:
Tips & Tricks Part 2 – Repairing Mics: Beyer M88, Shure Beta 52a,
https://www.youtube.com/watch?v=8miWDn57UZI
Let go deep inside and look for fixes on a Beyer M88 and Shure Beta 52a
Basically no-one makes these hands-on videos — helping the new blood of engineers — either because they don’t have the legitimate old school experience or they’re sadly too gone to speak in full sentences anymore. Step forward Dave. Legend isn’t the word. Your work is creating a body of easily-accessible and honestly-presented knowledge that needs to be on the radar of anyone interested in the practicalities (and engineering problems) of live sound. Fantastic.
Tomi Engdahl says:
Hear Microphone Polar Pattern & Distance Level Drop (Public)
https://www.youtube.com/watch?v=KTdGhqz_WgQ
Here is a simple way to hear the microphone polar pattern and proximity level changes of microphones. These tests will give a great indication of how much gain before feedback and how sensitive a mic will be when singing close and far.
00:00 Intro
00:09 Simple gear, complex concepts
01:02 Polar patterns
02:20 Test setup
02:54 Calibrate levels
03:35 Hear om7 vs Beta58A polar pattern
06:07 Level drop vs distance om7 vs Beta 58A
07:10 Polar and level drop Beta58a vs Telefunken M80
08:30 Polar and level drop Beta58a vs SM58
09:17 Polar and level drop Beta58a vs Heil PR35
10:52 Polar and level drop Beta58a vs Royer 122 Ribbon
11:54 Null in polar pattern vs polarity
13:22 Outro
Tomi Engdahl says:
Phantom Power Mic 6 Miles Cat5e Cable??
https://www.youtube.com/watch?v=SorO-QpqYRU
00:00 Intro and setup
02:14 100 meter (3 28 feet) test Shure SM58, AKG C414 and Neumann U89
04:24 800 meter (1/2 mile) test Shure SM58, AKG C414 and Neumann U89
06:57 1600 meter (1 mile) test Shure SM58, AKG C414 and Neumann U89
09:22 2400 meter (1.5 mile) test Shure SM58, AKG C414 and Neumann U89
11:46 4800 meter (3 mile) test Shure SM58, AKG C414 and Neumann U89
14:21 6400 meter (6 mile) test Shure SM58 and Neumann U89 ( I tested the C414 as well and it worked without issues, I skipped it as it performed the same as the U89)
16:21 Outro
Tomi Engdahl says:
Problems With Mono Sound From Stereo Speakers
https://www.youtube.com/watch?v=VHjdh-Vka-g
Demonstration of how to reduce comb filtering and audio interference issues from sound reinforcement systems.
00:00 Into
0037 Same sound from multiple points in space
01:40 Same signal vs different signal interactions
02:11 Multiple sounds from the same point in space
03:05 Unnatural sound assets and issues
04:05 Demo description
05:16 Single speaker pink noise
05:39 Same pink noise to two speakers
06:07 Same pink noise to two speakers with polarity reverse one speaker
06:26 Same pink noise to two speakers
06:32 Two different pink noise generators to each speaker
07:02 Two different pink noise generators to each speaker with one speaker polarity reversed
07:20 Summary
09:00 Multiple pink sources for measuring sound systems
09:26 Outro
Tomi Engdahl says:
How Does Phantom Power Affect Microphones?
https://www.youtube.com/watch?v=qTarfzrCGvI
Phantom Power does change the sound of your microphone, BUT HOW & is More Power Better, Worse, Too Much, or Not Enough?
Can Microphones Work with 12v if their Specs Says 48v?
In this video I test and compare multiple small and large diaphragm condenser and shotgun microphones with both 12 and 48v phantom power and use frequency analysis to find out how phantom voltage affects sound. If you have ever wondered whether phantom power really affects your microphone, this is for you.
Phantom Power – How to Avoid Damaging Your Microphones
https://www.youtube.com/watch?v=DZ5AdyreC4o
Phantom power is used to turn on any condenser microphone such as small pencil condenser mics, and large diaphragm vocal microphones. It is important to understand how to properly use these mics, and how to properly apply phantom power to turn on these mics.
Tomi Engdahl says:
Cupping mic
https://youtu.be/l6VhW_GJTlo
https://youtu.be/wJW29lbUv0U
Tomi Engdahl says:
DIY ribbon mic
https://www.youtube.com/watch?v=o_m8pnQ-QkI
Building a DIY Ribbon Mic
https://www.youtube.com/watch?v=0nWW8RuNACE
Tomi Engdahl says:
Microphone boosters?
https://groupdiy.com/threads/microphone-boosters.75923/
Tomi Engdahl says:
https://www.thatcorp.com/datashts/AES129_Designing_Mic_Preamps.pdf
Tomi Engdahl says:
https://www.richardmudhar.com/blog/using-piezo-contact-mics-right/
The sound to voltage conversion isn’t noted for its high quality – most piezo contact mics are tuned speaker elements used in reverse. The brass disc on which the element is glued is designed to resonate at the design frequency of 2-4kHz so that a large audio output is achieved with a small power input. This will tend to lead to a peakiness at mid-frequencies, which is why I glue these to a magnet to try and spread this peak and make the coupling to the source better.
However, the main reason these have gotten a bad rap is that many people couple them into a standard audio load, which loses low frequencies.
The reason why these devices often sound tinny is because the piezo sensor presents its signal through a series capacitance which is small, typically 15nF or less. When wired to a normal 50 kilohm line input this forms a 200Hz high-pass filter, which eliminates the bass.
If wired to a consumer plug-in-power microphone input of about 7 kilohms impedance, the result is a 1kHz high-pass filter. Hence the reputation for poor bass performance…..”
A piezo element can be thought of as a sound-dependent voltage source in series with a large capacitance of about 15nF. Here the trouble starts. You need to put this into a load which is higher than the impedance of the series capacitor at the lowest frequency of interest. If that is 20Hz, since the impedance of the capacitor is 1/2pifreq*C then you want that to be > 530k.
So what to people do? They go and stick this into the line input of their recorder, typical impedance 50k, or the plug-in-power mic input of their recorder, typical impedance about 7k, and they start to grouch that this damn thing sounds tinny. Which is does – from the frequency response you can see that the mic input starts losing low frequencies below 1kHz (red line) and the line starts to go below 200Hz (green line).
These things are very much like the crystal mics people used to use with valve open reel recorders in the 1950s/60s. Valves do high impedance really well, and inputs were often in the area of 1 megohm input impedance. The move to transistor circuitry meant consumer audio inputs tended to end up around 50k which is reasonably easy to do. Crystal mics also used the piezoelectric principle, and were valued for their low cost and high output voltage which overcame the preamplifier noise better. Transistorising audio gear killed off the crystal mic as they sounded tinny and harsh with the lower input impedances for the same reason.
Piezo contact microphone hi-Z amplifier using a FET
http://www.richardmudhar.com/piezo-contact-microphone-hi-z-amplifier-using-a-fet/
Piezo contact microphone hi-Z amplifier – low noise version
http://www.richardmudhar.com/piezo-contact-microphone-hi-z-amplifier-low-noise-version/
Tomi Engdahl says:
Do Vocal Mics Go Bad? Lets Hear what happens!
https://www.youtube.com/watch?v=0gIrgXsioQE
Null testing vocal mics to hear degradation do to build up of spit and other issues
Tomi Engdahl says:
Lav Mic EQ & Processing For Corporate Shows
https://www.youtube.com/watch?v=Az3pw2qLiWA
01:26 – Mic placement as an A2
02:49 – System Design & Processing
05:52 – Channel Strip & Subgroup Processing on Console
18:53 – Mixing Techniques
Tomi Engdahl says:
https://www.dpamicrophones.com/mic-university/the-basics-about-distortion-in-mics
Tomi Engdahl says:
How To Eliminate Microphone Feedback | 5 Must-Know Tips
https://www.youtube.com/watch?v=z2ceO8D_MUw
What causes microphone feedback? How can you eliminate mic feedback to prevent the squealing, howling, or screeching sound of feedback from ruining your live performance? In this video, I’ll teach you how to set up your PA system and ring out stage monitor wedges to prevent microphone feedback before the show begins.
0:00 – Introduction
0:16 – What Causes Microphone Feedback?
1:03 – Tip #1
2:32 – Tip #2
3:19 – Tip #3
5:20 – Tip #4
6:26 – Tip #5
7:31 – Bonus Tip (Tip #6)
7:49 – Subscribe To Audio University!
https://audiouniversityonline.com/5-steps-to-eliminate-microphone-feedback/
Tomi Engdahl says:
The Magic of Tube Microphones! – Marc Daniel Nelson
https://www.youtube.com/watch?v=0eCn99sxdSQ
In this episode of MakeMineMusic, Marc Daniel Nelson shares his experiences and stories of
the magic of Tube Microphones. Join him in this fireside chat as he breaks down his personal
experiences with a vast array of microphones.
C12 by AKG
AKG’s C12 is one of the best-known tube condenser microphones in history. It is a side-address, large-diaphragm design based on AKG’s CK12 capsule, a 6072 dual-triode glass tube, and a transformer-coupled output circuit.
Telefunken ELA M 251 (AKG made)
Arguably one the most beautiful microphones ever produced, the TELEFUNKEN ELA M 251E has been featured on countless hits and classic recordings over the decades. Today, prime examples of vintage ELA M 250 / 251 (both “E” and “non E”) microphones have become rare and highly sought after jewels, commanding tens of thousands of dollars on the vintage market.
Neumann M50
The Neumann M50 is a pressure-type microphone with non-directional characteristics. After its introduction in 1950, the outstanding tonal quality and omnidirectional pattern of the Neumann M50 made it the gold standard for the recording of symphony orchestras, either with the single-microphone technique, a stereo pair, or the Decca Tree for three-track recordings.
Neumann M49
The M49 has a dual-diaphragm design, which allowed it to become the first condenser microphone with a remotely switchable pickup pattern having constant sensitivity: the psu doubles as a pattern selector, with a continuously-variable potentiometer for choosing cardioid, omni-directional, figure-eight or any position in-between the three.
Neumann U67
The U 67 was developed to replace the venerable U 47 as the company’s flagship large-diaphragm condenser. The U 67 is incredibly versatile. No source is off limits; its high SPL handling, ruler-flat frequency response, detailed midrange, and sweet, velvety character with a hint of delicate airiness make it a first-call mic for drums, piano, acoustic and electric guitars, strings, woodwinds, brass, percussion, and vocals.
Neumann M269
The M 269 is a large-diaphragm, multipattern tube condenser microphone. It is a variation of the Neumann U-67, developed as a way to sell the U-67 to the German broadcast market.
Neumann U47
The Neumann U 47 is the granddaddy of large diaphragm condenser microphones and features a legendary sound that has captured the vocal stylings of the greatest singers in the modern era. The Beatles used it to great effect, as did Frank Sinatra. From Ella to Adele, the Kingston Trio to the King of Pop, the vocal sounds of jazz and rock, folk and pop would not be the same without a U 47 in the studio.
Tomi Engdahl says:
$30 DIY Shure SM7B Microphone!
https://m.youtube.com/watch?v=tdt8GCBKEHk&feature=youtu.be
Tomi Engdahl says:
SM7B vs SM58 Mic SHOWDOWN
https://youtu.be/FPO8dfE9inY
https://youtu.be/DPw0-UHq3f8
Tomi Engdahl says:
https://hackaday.com/2022/10/02/camera-mounted-stereo-mic-is-fluffy-and-capable/
Tomi Engdahl says:
Test – Do Audio Transformers Mess Up Sound? – Part 1
https://www.youtube.com/watch?v=so_sXkH8QOk
Lets see and hear the impact on the sound of having an isolation transformer connected to an Audix TR40 measurement mic and a Shure Beta 58
00:00 Introduction
00:54 Transformer Specs Radial JS3, Twin ISO Whirlwind ISO2
02:14 Crimson, Cinemag and Lundahl
02:48 Do transformers hurt the sound?
04:16 The test setup
06:35 Baseline curve with Audix TR40 mic and hardwire split
08:41 Compare Audix TR40 into 1 vs 2 console channels hardwire
09:48 Impact of Whirlwind ISO2 connected to TR40 mic
11:20 Transformer alters sound of mic everywhere
12:35 impact of Radial JS3 connected to TR40 mic
13:53 Impact of Whirlwind ISO2 connected to Beta58
15:52 impact of Radial JS3 connected to TR40 mic
16:38 Outro
Tomi Engdahl says:
https://hackaday.io/project/188265-external-mic-for-phone-timegrapher-app
Tomi Engdahl says:
There are 4 types of microphone:
Dynamic Microphones.
Large Diaphram Condensor Microphones.
Small Diaphram Condensor Microphones.
Ribbon Microphones.
https://blog.landr.com/microphone-types/
Tomi Engdahl says:
PROXIMITY EFFECT IN MICROPHONES EXPLAINED – HOW IT AFFECTS DIFFERENT SOUND SOURCES
https://www.dpamicrophones.com/mic-university/source-dependent-proximity-effect-in-microphones
Proximity is when a microphone produces more bass by getting closer to the sound source (a point – or line source). This article takes you through some of the basics of proximity – and introduces a more advanced perspective on the phenomenon.
The effect of proximity is well-known to most sound engineers. The singer’s voice gets more bass when the microphone moves closer to the mouth. As the microphone moves away, the sound gets thinner.
Proximity only exists with gradient-types of microphones – wide cardioid, open cardioid, cardioid, super-cardioid, hyper-cardioid, figure of eight – and everything in between. Thus, the closer the directionality pattern comes to a figure of eight, the more proximity is exhibited. Also, the proximity effect is strongest on-axis. If you turn the microphone, the proximity effect is reduced.
Note that the proximity effect, by design, sometimes provides a flat response when the mic is close to the source (i.e., vocal microphones) – or provides a flat response when the microphone is further than 1 meter away from the sound source (in distant recording or the like). For this reason, when evaluating this information for gradient microphones (for example in a spec sheet), the distance at which the frequency response is neutral/flat should be stated.
The sound sources
Proximity is dependent on the sound source. A point source generates a spherical sound field where the SPL drops by 6 dB/doubling distance. A gradient microphone close to a point source (1 m), practically no proximity effect exists.
The SPL from point sources drops by 6 dB/doubling of distance.
The SPL from line sources drops by 3 dB/doubling of distance.
The SPL from plane sources drops by 0 dB/doubling of distance.
To conclude, we have a bass lift when the microphone is close to a point source.
When proximity?
Basically, proximity effect occurs when sound comes from a point source or a line source, the microphone is a gradient type, and it is pointing towards the sound source. Proximity effect does not occur when the sound source is a plane source, the microphone is a pressure type, or the microphone is pointing to the side. However, in between these specific conditions, there are variations.
Trumpet
Sometimes, the proximity effect does not come into play due to the instrument’s frequency response. For instance, a trumpet is basically defined as a point source. However, the spectrum does not extend to the bass range. Thus, proximity is not a challenge when recording this instrument.
Grand Piano
A grand piano (the space just above the strings) is regarded as a plane source even though the individual strings might be seen as something else. The levels are relatively constant at 2, 4, 8 and 16 cm. There is no proximity effect (nothing to emphasize low frequencies).
Acoustic guitar
An acoustic guitar (microphones centered at the front of the top wood sound board, below the bridge) is a plane source at small distances. However, the spectrum is not that attractive in this position, so other microphone positions are usually preferred, mostly because the sound from the body hole is strong here.
Kick drum
You might expect the drumhead of a kick drum to function as a plane source due to the significant diameter of the skin. However, its behavior is closer to a point source. The drumhead is not a pure plane source at any distance – so proximity exists.
Tomi Engdahl says:
A Binaural Microphone For The Great Outdoors
https://hackaday.com/2022/12/17/a-binaural-microphone-for-the-great-outdoors/
A binaural recording is designed to mimic as closely as possible the experience of listening through human ears, and thus binaural microphones are often shaped like the human head with the microphone cartridges placed where the ears would be. That’s not the only way to make a binaural microphone though, and the Crown Stereo Ambient Sampling System, or SASS, did the same thing with a pair of pressure zone microphones for outdoor recordings. [Filip Mulier] doesn’t have one of the originals, but he’s done his best to make a SASS-like microphone of his own.
SASS-style Stereo Microphone for Nature Recording
A high quality weatherized microphone for stereo recordings outdoors.
https://hackaday.io/project/188609-sass-style-stereo-microphone-for-nature-recording
Tomi Engdahl says:
A Simple High-Fidelity DIY Mic Pre Amp
https://hackaday.com/2022/12/16/a-simple-high-fidelity-diy-mic-pre-amp/
If you’re doing any serious work with microphones, you’ll typically find yourself in want of a dedicated preamp. [ojg] needed just such a thing for acoustic measurement duties, and set about working up a cheap DIY design by the name of ThatMicPre.
The design is based around the THAT1510 preamp IC, known for its good frequency response and low harmonic distortion and noise. The design is also compatible with THAT1512, SSM2019, and INA217 chips as well. [ojg] gave the design switch-controlled gain levels, providing greater accuracy than a potentiometer adjustment, and the ability to supply phantom power for mics that require it. The PCB is designed to rely on through-hole parts and common connectors for easy assembly.
https://github.com/ojg/thatmicpre
Tomi Engdahl says:
https://hackaday.com/2022/12/17/diy-square-guitar-is-anything-but/
Tomi Engdahl says:
Microphones: An abundance of options for capturing tones
https://www.edn.com/microphones-an-abundance-of-options-for-capturing-tones/
Tomi Engdahl says:
Meghan Markle Used A Neumann Mic To Make Her Spotify Podcasts Sound Warm And Engaging
https://www.forbes.com/sites/marksparrow/2023/01/02/meghan-markle-used-a-neumann-mic-to-make-her-spotify-podcasts-sound-warm-and-engaging/?sh=137815482087
When Spotify signed up Meghan Markle – the Duchess of Sussex – to present a series of podcasts for a staggering $20m, the streaming giant was duty-bound to ensure the Duchess sounded great. The words in the podcast may have been Meghan’s, but the sound of those words was down to Neumann, the legendary German microphone manufacturer that’s part of the Sennheiser Group.
I finally identified the model as a Neumann BCM 705
There is a condenser variant of the BCM 705 (the Neumann BCM 104), but the green Neumann logo identified it as a dynamic design rather than the more usual red. Dynamic microphones are far better at rejecting room noise, which is essential for recording on location rather than in a sound-proofed recording studio.
I should have known that in such a high-profile production, the producers would use something like a Neumann or the ubiquitous Shure SM7B. The Neumann looks far more elegant and sounds warmer to my ears. The BCM 705 is also relatively well-priced and designed for broadcasting and podcasting with the ability to bring out emotion in a voice.
Inside the BCM 709, there’s a dynamic capsule voiced for a smooth and clear sound with excellent speech intelligibility. The hyper-cardioid pickup pattern and internal shock mount and pop filter minimize unwanted room sounds, making it ideal for recording in untreated spaces while on location.
Neumann developed the BCM 709 with radio DJs, podcasters and talk show hosts specifically in mind, but the design also performs well for announcers, newscasters and voiceovers. The BCM 705 excels at conveying emotion and pulls out the warmth in a speaker’s voice. The shape of the microphone makes it ideal for use on a boom arm, enabling it to be mounted horizontally or vertically. For video streamers, the BCM 709 is ideal when mounted in a horizontal position, as it won’t obscure the face.
The BCM 705’s frequency response is specifically tailored for the human voice. It has a gentle presence boost above 2kHz to enhance speech intelligibility. At the same time, its soft bass roll-off compensates for the proximity effect, creating a low-end which is full but never boomy.
The Neumann BCM 705 doesn’t require phantom power and it’s easy to set up. Connect it to a USB audio interface or digital recorder using an XLR cable, and you’re ready to broadcast live or record a podcast. Although it’s primarily designed for broadcasting and podcasts, the BCM 709 can shine in the recording studio. Its dynamic design soaks up high sound pressure levels enabling it to capture powerful vocals or a blast from a brass section.
Verdict: The Neumann BCM 709 is a superb dynamic microphone with a pressure gradient transducer ideal for podcasting, announcing and streaming. It has many of the excellent characteristics of a traditional condenser microphone, but it can sound like a studio microphone, even in an untreated room. The built-in pop filter and anti-rumble suspension make it incredibly versatile and excellent at rejecting unwanted sounds, no matter where it is used. It does need a fair amount of gain, but the noise floor is excellent
Pricing & Availability: The Neumann BCM 709 dynamic microphone is available from Neumann distributors and costs $729 / £569 / €649.
Tomi Engdahl says:
Microphones: On-PCB options for catching tones
https://www.edn.com/microphones-on-pcb-options-for-catching-tones/
Tomi Engdahl says:
The sound of music, according to physicists
https://phys.org/news/2015-07-music-physicists.html
For almost two years, this physics grad student has been testing how sound radiates from live musical instruments, which includes hearing the same song over and over… and over. But the monotony has a purpose; it’s all about helping musicians, instrument makers, concert hall designers, audio engineers and music producers enhance sound quality.
The work takes place in one of two anechoic chambers at BYU. Anechoic, meaning “free from echoes and reverberation,” describes a room built with walls that absorb sound energy, so noise can’t bounce back to a listener.
Bodon and physics professor Timothy Leishman devised a recording system with a rotating chair and a semicircular array of 37 microphones that puts musicians out of their comfort zone.
Tomi Engdahl says:
Better GoPro Sound – No External Mic
https://www.youtube.com/watch?v=qINqqMym-Ok
GoPro is known for crap sound and everyone recommends external mics which is all good if ya want to carry around extra stuff and wires and a mess.
But if you just want or need to derive a decent audio file from your camera, here are some settings and a listen to the differences. Also I dive into the 3 mics on a GoPro Hero5 and what makes up the wav file.