Science that explains why we hear differences in cables?


Here are some excerpts from a review of the Silversmith Audio Fidelium speaker cables by Greg Weaver at Enjoy The Music.com. Jeff Smith is their designer. I have not heard these cables, so I don’t have any relevant opinion on their merit. What I find very interesting is the discussion of the scientific model widely used to design cables, and why it may not be adequate to explain what we hear. Yes it’s long, so, to cut to the chase, I pulled out the key paragraph at the top:


“He points out that the waveguide physics model explains very nicely why interconnect, loudspeaker, digital, and power cables do affect sound quality. And further, it can also be used to describe and understand other sonic cable mysteries, like why cables can sound distinctly different after they have been cryogenically treated, or when they are raised off the floor and carpet.”


“One of the first things that stand out in conversation with Jeff about his cables is that he eschews the standard inductance/capacitance/resistance/impedance dance and talks about wave propagation; his designs are based solely upon the physics model of electricity as electromagnetic wave energy instead of electron flow.


While Jeff modestly suggests that he is one of only "a few" cable designers to base his designs upon the physics model of electricity as electromagnetic wave energy instead of the movement, or "flow," of electrons, I can tell you that he is the only one I’ve spoken with in my over four decades exploring audio cables and their design to even mention, let alone champion, this philosophy.


Cable manufacturers tend to focus on what Jeff sees as the more simplified engineering concepts of electron flow, impedance matching, and optimizing inductance and capacitance. By manipulating their physical geometry to control LCR (inductance, capacitance, and resistance) values, they try to achieve what they believe to be the most ideal relationship between those parameters and, therefore, deliver an optimized electron flow. Jeff goes as far as to state that, within the realm of normal cable design, the LRC characteristics of cables will not have any effect on the frequency response.


As this is the very argument that all the cable flat-Earther’s out there use to support their contention that cables can’t possibly affect the sound, it seriously complicates things, almost to the point of impossibility, when trying to explain how and why interconnect, speaker, digital, and power cables have a demonstrably audible effect on a systems resultant sonic tapestry.


He points out that the waveguide physics model explains very nicely why interconnect, loudspeaker, digital, and power cables do affect sound quality. And further, it can also be used to describe and understand other sonic cable mysteries, like why cables can sound distinctly different after they have been cryogenically treated, or when they are raised off the floor and carpet.


As such, his design goal is to control the interaction between the electromagnetic wave and the conductor, effectively minimizing the phase errors caused by that interaction. Jeff states that physics says that the larger the conductor, the greater the phase error, and that error increases as both the number of conductors increase (assuming the same conductor size), and as the radial speed of the electromagnetic wave within the conductor decreases. Following this theory, the optimum cable would have the smallest or thinnest conductors possible, as a single, solid core conductor per polarity, and should be made of metal with the fastest waveform transmission speed possible.


Jeff stresses that it is not important to understand the math so much as it is to understand the concept of electrical energy flow that the math describes. The energy flow in cables is not electrons through the wire, regardless of the more common analogy of water coursing through a pipe. Instead, the energy is transmitted in the dielectric material (air, Teflon, etc.) between the positive and negative conductors as electromagnetic energy, with the wires acting as waveguides. The math shows that it is the dielectric material that determines the speed of that transmission, so the better the dielectric, the closer the transmission speed is to the speed of light.


Though electromagnetic energy also penetrates into and through the metal conductor material, the radial penetration speed is not a high percentage of the speed of light. Rather, it only ranges from about 3 to 60 meters per second over the frequency range of human hearing. That is exceptionally slow!


Jeff adds, "That secondary energy wave is now an error, or memory, wave. The thicker the conductor, the higher the error, as it takes longer for the energy to penetrate. We interpret (hear) the contribution of this error wave (now combined with the original signal) as more bloated and boomy bass, bright and harsh treble, with the loss of dynamics, poor imaging and soundstage, and a lack of transparency and detail.


Perhaps a useful analogy is a listening room with hard, reflective walls, ceilings, and floors and no acoustic treatment. While we hear the primary sound directly from the speakers, we also hear the reflected sound that bounces off all the hard room surfaces before it arrives at our ears. That second soundwave confuses our brains and degrades the overall sound quality, yielding harsh treble and boomy bass, especially if you’re near a wall.


That secondary or error signal produced by the cable (basically) has the same effect. Any thick metal in the chain, including transformers, most binding posts, RCA / XLR connectors, sockets, wire wound inductors, etc., will magnify these errors. However, as a conductor gets smaller, the penetration time decreases, as does the degree of phase error. The logic behind a ribbon or foil conductor is that it is so thin that the penetration time is greatly reduced, yet it also maintains a large enough overall gauge to keep resistance low.”


For those interested, here is more info from the Silversmith site, with links to a highly technical explanation of the waveguide model and it’s relevance to audio cables:


https://silversmithaudio.com/cable-theory/


tommylion
We live in a capitalist country. If you do not research/study these things independently, then you very well may fall sway to the honey coated sweet nothings being whispered into your ears… 

There is no provision or amendment in the constitution that says for profit companies have to have the consumers best interests at heart.

any cable fetish type bother to peek under the hood of their equipment? The wires inside don’t seem to be very impressive.. 

Yet the 27 caret solid unobtainaim core with unicorn mane outer braid will bring out the mini/macro dynamics…all for $5,000 per 1/4 meter….

and John dunlavy was a exceptional producer of speakers.. it’s low class to disparage the deceased when many recording studios use(d) his products..


@theaudiotweak 

Thanks for the video link. I am only part-way through, but consider it to be very insightful, and particularly useful for those of us who do not have engineering backgrounds.
So it would be O.K. to disparage John D if he were alive? Plus I didnt disparage I just stated that I am not convinced that he is the ideal spokesperson for all things audio. Also I should remind you that JBLs were a darling of recording studios for years and these speakers stunk.  
Perkri, I want to tell you that I enjoyed very much your post regarding the comparison between recorded images and recorded sound, as it gave me much to think about. However, I do not think it is an accurate comparison, and that I believe you may have made a categorical mistake.

You see, the cave paintings at lescaux and others actually began as ‘expressions’, creative or otherwise, that the fact of their being recorded were mere default outcomes of the expression itself - they were not originally intended to be recordings, the medium of which simply allowed the recording to occur. In much the same way as the prehistoric expression of sound began as simply that, an ‘expression’, to which no default record of that expression was available at the time, since the default medium of sound as air waves was, and still is, transient.

In line with this logic, one can say that the ‘expression’ of images and sound may have indeed occurred in prehistory at about the same time, in fact, in much the same way that little by way of time separates the intended recording of the visible world by way of photography from the intended recording of sound waves - gauged in relation to the duration of the human species.

It was a categorical mistake to associate and thus compare the act of expression with an act of recording. The visual act of expression is intrinsic related to its medium of record, while the audible act of expression can be entirely independent of it. I hope this makes sense.

From the viewpoint of prehistoric survival, it could indeed be argued that both sight and sound, had to evolve in tandem. 

And, in similar vein, it can be argued that seeing is no different from hearing - they both take years of experience to perceive well, observantly, and insightfully. There are as many people who look but do not see, as there are who hear, but are unable to listen.

In friendship, kevin : )