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

Showing 11 responses by holmz

Also interesting is that what is seen on the scope matches what is heard from different cables. Impedance mismatches do seem to create ringing distortion. This colors instrumental tones and textures, alters characteristic instrumental timbre, and so the less of it the better

The guys using a Time Domain Reflectometer machine to fix the internet yesterday did exactly that.

But the speed of light and the speed of electrons is about 3e8 m/secs, and the speed of sound is about 3e2 m.sec, so roughy a million times different.

Those ringing waves and echos would need to be caught in a crossover or something like a capacitor or inductor to hold them long enough to be around to be heard.
(Or am I missing something?)


I think I’ll just try and keep my cables short by keeping my amp close to speaker.

Plus most speakers do not have special cables inside of them, and nor do the amplifiers, so unless the speaker cables are a lot longer, then I am sort of stuck with the sonics of what is in the speaker and amplifier.

Even those plate amps like Hypex and Purify have normal wires and they just hook up to the normal wires that grace the drivers.
Good catch on the speed… it is the speed of electricity, like you said, and not the speed of the electrons.

I get the impedance mismatch on on say a 50 ohm connection, but what is the mismatch on a near zero ohm cable versus a speaker input to the crossover?

Was that o-scope X-Axis scale in the audio regime? Or a lot higher in frequency?

Are there any plots of these echo waves?

Whatever wire is inside a speaker, what does that have to do with anything? That is as lame as "power travels 500 miles what difference can the last 5 feet make?" Ringing is ringing. Are you saying less isn't better? What are you saying anyway? Besides some internet guys did something on the internet?

I am saying if the amp is directly connected to the speaker with say a 1” wire at 0 ohms, that seems optimal.
And if that wire was say a foot long, and the wires inside of the amplifier and also in the speaker are both a foot long at 16 gauge… then the effect of a foot long wire at 10 gauge connecting them seems to have a bot less of an effect?

If the capacitance of the wire causes the amplifier to oscillate than that is clearly significant.
It would be nice to seen example of  this radial ringing that you speak of.
Your 40 years of "selling" your cables dont beat acoustic, psycho-acoustic and all speakers designers experience in the world...

I think he is claiming that his 40 years is in-line with the psycho-acoustic part. Which makes sense if he was selling cable to people and using psychological methods.

Speaker designers are different than the cable people.

Then i will say that cables could be miraculously good but they will not replace marvellous speaker nor room acoustic like someone just said erroneously...

To my eye that the poster was using sarcasm when “the Odin cables paired with Logitech” was presented.
Given the ABSURD claims of many audiophiles/audiophools, I find it absolutely hysterical that the NON believers (ie. the SANE sector of the "audiophile community" are the ones being labelled as "Flat Earthers".
I rather think you've got your cryogenically-treated wires crossed! Cables raised off the floor?? That's a nutty as the nuttiest Flat Earther.

We really need a collective term for a group of nutty audiophiles. Maybe a Placebo of Audiophiles. An Idiocity of audiophiles? A mid-life-crisis of Audiophiles? A Brainwashing of Audiophiles? So many great possibilities.

Buffaloes have a group as an “obstinancy”.However here is no word for a group of chefs.

The idea of a Heston chef approach where one cryogenically cools the cables in liquid nitrogen, and then needs to cook, or “burn in” cables has a sort of witches brew, or cauldron feel to it… So coven comes to mind.
Maybe “A Resonancy of Audiophiles” since there is a group think to it?
Then i apologize if sometimes by my lack of the mastery of english language i mistake sarcasm with claim....

But he also said that cables are more important than speakers... Is it a sarcasm too?

Yes I believe so.In the limit where one just has a $100k cable and no speaker, then the cable will not make magic.


My point is all changes are important, cables included, but their meaning and characteristics CANNOT be assessed WITHOUT acoustic treatment and control over a room related to the specific speakers charracteristics...
If an RCA, or a speaker cable, cannot be AB identified in a 1/2 blind test, then one could argue that they are not in the group of “All changes are important”.


And why does it bother you what someone does with their money?
Guess you just want them to know what you do, right? Because you are the be all and end all of audio knowledge because you were a button pusher in a studio?

Most of those studios are running specific interconnect cables that are not “magical”… they are just using shielded twisted pairs with low capacitance and inductance. Anything that enters the CD is either coloured by them, or it has not been coloured.
If I use those same cables on my playback system, then will it sound different than if I use some high $ cables? And why are the studios not using kilo-$ interconnect cables?


With a liquid metal cable, for the liquid metal, it is all surface. there is no depth to penetrate. It is ’liquid’ down at the molecular alloy level, which is about as close to being a pure atomic/pure element level fluid, as you’ll ever get to. Conductive. 
Usually metals are most conductive as we approach 0 Kelvin. I am not sure how one makes a classical atom, or molecule, or alloy of copper (or silver) metal differ from the known melting point and boiling points that have been observed for centuries?
And how would a liquid version of it stay put?
I would assume it would drop out like a melting fuse
So I was assuming ^that stuff^ was what this quote was referencing:
Given the ABSURD claims of many audiophiles/audiophools, I find it absolutely hysterical that the NON believers (ie. the SANE sector of the "audiophile community" are the ones being labelled as "Flat Earthers".
There’s 3 electrical parameters in poor quality cables that "can" influence the sound.
A combination of Resistance, Inductance and Capacitance, which ’’can" create filters with the output impedance of the source/input impedance of the load

You find all three parameters used in speaker xovers to roll off the individual speaker drivers into each other, so they work "hopefully" as a summed flat response.

Then is it possible to use a neutral cable and a DSP?

With the title being “Science can explain…”, it is hard to believe that these cables can sound different when there is no scientific proof that the signal going through them has any measured difference.

If they are shown to be able to identified subjectively as different, then we would be in a different place and could at least know that they are different.
Coincidentally there is a recent review in audio science review in which RCA cables from three distributors, with fairly wide price differences, are compared from both a performance and an auditory perspective. No significant differences were found

https://secure.aes.org/forum/pubs/journal/?ID=979


That's funny AES did a study and found the opposite. I would trust AES over ASR any day of the week.


Do you have link to ^that^ AES study?
So, either I buy into skin effect, waveguide, blah blah blah, or... I believe this is caused by gear and ears being more sensitive than the pure math shows.

Given those two choices, I pick the latter, simpler version.

The third column is the psychological aspect of expectation.
That is a whole bundle of interesting and confusing stuff.

“CEO/Designer Jeffrey Smith is a Wyoming native and a graduate of the United States Naval Academy with a Bachelor of Science degree in General Engineering. He also earned a Master of Science Degree, With Distinction, in Defense and Strategic Studies / Weapons of Mass Destruction Studies from Missouri State University and was a National Defense University Countering Weapons of Mass Destruction Fellow. His initial tours in the Navy included assignments in which he studied sound transmission in and worked with the acoustic environments of some of the world's oceans.”

And a minor in weapons of mass distraction?