Having needed an audio cable recently for the lab, I was saddened to see the poor quality of some off-the-shelf pre-assembled cables. I didn’t realize poor audio cables were still a phenomenon in the 21st century. It got me wondering, how can we test and compare cables and complete cable assemblies?

It is an important question because many are forced to spend a small fortune on cables each time any hi-fi or audio/visual product is purchased from stores – the products do not come with the cables, and stores charge a premium for them because they know users won’t want to wait a further day or more to buy something cheaper and better online – especially at Christmas when the postal service is struggling.

All sorts of ‘techniques’ are used. As an example see the ‘gold-plated optical cable’. Incidentally the plating at a guess might cost just pennies or less, but a high premium is demanded for it – despite the fact that no property of gold is useful for optical signaling purposes. Gold has a high perceived value even if the quantity of it is tiny. The wording is always clever to leave a certain impression yet tell no lie.

The cables below may be really good. I have no idea, I have not tried them. Yet the prices are impressive. These screenshots are cropped and reduced in size for fair use as examples of price versus listed features.

This post investigates how sometimes we can do better ourselves at a fraction of the cost of some pre-assembled cables – and we’re going to avoid anything non-persuasive (i.e. anything we can’t throw available test equipment at to prove or disprove), so no ‘directional’ conductors or oxygen-free copper or silver wires or Kevlar shielding allowed!. However, all comments and suggestions would be gratefully received – I know there are probably many practical considerations such as cable flexibility and durability which are of concern to users. Therefore the information here is more of use for a home environment until there is feedback from people on whether it is useful for studio or live performances too or what modifications they would prefer such as ultra-flexible cables. This post also examines how we can test off-the-shelf and home-made cables and see how good or bad they really are.

What things would we want to see in good audio cable assemblies?

Everyone will have different requirements but from a general point of view these requirements would come out pretty high:

100% coverage shielded cables, grounded, to minimise capacitive pickup and RF pickup
Two and three cores for flexibility. The two-cored cable could be used for mono or stereo applications; for mono use one of the cores would provide the audio signal and the other core would be used for the ground connection. The shield would be grounded at one end. For stereo use, the three core cable could be used, and the shield would be used as the ground connection at one end. For balanced audio use (e.g. with XLR connectors) then again either cable could be used.
Ideally a controlled pair cable for balanced audio applications, to reduce the effects of as many modes of noise pickup as possible

Introduction
Much has been written about digital audio, its defining standards, the ever-
changing hardware and software, the various applications in recording and
broadcasting and telecommunications and the audibility of this or that configu-
ration or artifact. In this book the late Julian Dunn focused instead on the mea-
surement of digital audio signals, and examined in great detail techniques to
evaluate the performance of the converters and interface through which the audio passes.

Ideally every cable should transfer a signal between two items of equipment
with zero loss and distortion. In the real world this is not possible because subtle
changes occur in the signal and these may result in readily perceived changes to
sound or video quality. The degree of signal degradation is determined directly by
the design of the cable.
Maximising real world cable performance requires an understanding of the signal
transmission process and the engineering tools available, to ensure that the signal
arrives in the best possible condition

In this video ‘Audiophile Interconnect Testing – do cables make a difference?’ I’ll be using the Omicron Lab Bode 100. #OmicronLab #Bode100