More speaker cable "stuff"- the Silversmith Audio Fidelium Loudspeaker cables.

[wyn palmer]

A friend purchased a "Fidelium Loudspeaker cable" at about $1500 for 10' and installed it in his system, claiming how much better it sounded than his old cable. To my ears it seemed to mute the dynamics and generally make everything a bit too mid range heavy for my taste.
He referred me to their web site where the designer has a white paper on the design, including a bunch of electromagnetism equations, where he claims certain wonderful properties for the cable, mostly to do with treating the cable as a waveguide.
Naturally he asked my opinion, and I volunteered to critique the paper, and measure/review the cables on my home system, with the intention of doing a follow up on his system afterwards.
So, here are the results.
I'll split it into a number of posts, covering various aspects of the evaluation.


The cables are as above.
A review.
Silversmith Audio Fidelium Loudspeaker Cables A new paradigm in speaker cables. Review By Greg Weaver (enjoythemusic.com)
Silversmith Audio Fidelium Speaker Cables Review! ~ The Sound Advocate
There are more.
FIDELIUM SPEAKER & INTERCONNECT CABLES. Thin foil (ribbon) design derived from electromagnetic wave and waveguide physics to minimize skin-effect phase errors. The skin effect properties of FIDELIUM are up to 33 times superior to copper or silver. (silversmithaudio.com)

 

[wyn palmer]

I measured the electrical parameters of the cable- the R and L at a variety of frequencies and the C at 1kHz.
One of the designer's claims was that the cable eliminates skin effect in the audio range- essentially because the conductor is very thin and wide.
That should have the effect of making the resistance and inductance essentially independent of frequency.
So what did it do.
R: 2.45ohms/100Hz, 2.452ohms/1kHz, 2.457ohms/10kHz, 2.464 ohms/100kHz.
L: 2.8uH/1kHz, 2.49uH/10kHz, 2.56uH/100kHz.
C= 76pF
I'd say that they did what they claimed- there is no measurable skin effect in the audio band.

So far so good.
However- look at that DC resistance- I'm sure that will have a very significant effect with my speakers/amp.


Green is the frequency response at the output of the amp. Blue is measured at the speaker terminals.
NO ADDITIONAL RESISTIVE ATTENUATOR WAS USED.
The measurement was made directly across the terminals in both cases, just being careful not to damage the RME ADC/DAC.
As you can see the resulting frequency response is highly modified.
In fact, it looks pretty well exactly as the simulations using the RLC and the models for the amp output and the speaker input say it should.
I can't say exactly how it will behave in my friend's system- that will have to wait until I can measure it- but you can bet your boots that it won't be anything approaching flat due to the load impedance variations presented by his speakers.

 

[wyn palmer]

The next aspect was the theory that the designer espoused.
Let's start by looking at the square wave response of the system- DAC, preamp, power amp, speaker cables, speaker load, ADC.

First a 1kHz square wave at the amp out (blue) and speaker in (yellow)



As you can see the square waves are pretty decent- considering what the signal goes through, and except for a bit more noise on the
speaker input they are virtually identical.
Incidentally the noise is there even if there is no signal- but the probes are fairly well separated and the ground connection for the yellow one goes through a longish wire, so it's not surprising.
Next a close up of the rising edge of the waveforms to show delay.




As you can see the traces are separated by c.1us.
This will become important in the next posting where I comment on the "white paper".
Incidentally, measuring the responses using my usual short Mogami 2921 cable is not noticeably different as far as the square wave is concerned, including the delay, and it has appreciable levels of skin effect and yet it has a much flatter frequency response.

 

[wyn palmer]

I'm not going to comment too much on the paper. The math presented seems like a direct copy from EE early undergraduate courses on electromagnetism and can be found on line.
The conclusions essentially are that due to conduction/skin effect issues the audio signal propagates through the cable at a speed which is a fraction- in the order of 10%- of the speed of sound.
Thus, transmission line effects are important, as is the microstructure of the conductor, which cause internal reflections "muddying" the sound.
This justifies all of the choices that were made in the design of his cables.
Yes, they would be important if his conclusions were indeed true- i.e. the speed of sound is c. 340m/s, so the waveform would propagate at 34m/s and the 10 ft (3m) cables would be a half wavelength at c. 5Hz! It would also mean that the delay would be in the order of 100ms, not 1us!
He is correct that the two conductors- the one from the amp to the speaker and the return one from the speaker to the amp- do form a transmission line. What he gets wrong is the frequency scale at which this becomes important.
Clearly the author didn't learn about the Poynting vector and the transfer of energy in a conductor/transmission line- which essentially means that the energy is transferred in the EM fields and not within the conductor itself- and hence is governed by the permeability and permittivity of the dielectric between the two "plates" of the cables. They generally teach that in 4th year EE and graduate level Physics in the US. Thus, the "energy" propagates at c. 50% of the speed of light or in the order of 5 million times faster than he states.
That made all of his conclusions concerning dispersion and reflections and the effect of imperfections/dislocations in the conductor entirely spurious.

 

[NH-MAN]

Any guesses on what the FIDELIUM alloy is?

 

[wyn palmer]

Any guesses on what the FIDELIUM alloy is?

I don't know but I can speculate.
Skin depth is related to the inverse of the conductivity. So, in order to achieve the stated goals, it needs to be low conductivity and able to be deposited on the plastic substrate.
Industrial: Design Guide - Conductivity of Alloy Classes (copper.org)
Industrial: Design Guide - Conductivity of Specialty Alloys (copper.org)
It really hardly matters as the argument for its use is just amusingly wrong.

 

[El Rubio]

Any guesses on what the FIDELIUM alloy is?

Wanna know what “Fidelium” is? Check the US patent Office. If they truly believe their alloy and designs are “evolutionary and revolutionary”, they would protect them. Could be somebody else’s alloy that they discovered during a tragic ‘Schmelting’ accident.

 

[Fairlane]

Very impressive research wyn, you clearly know your stuff. Enjoyed reading your results.

Think I will stick with my #14 seaker wire and pocket the $$$ difference.

 

[wyn palmer]

For comparison, here are the RLC measurements for a 10AWG Knukoncepts Kord speaker cable.
C: 197pF.
L: 1.95uH/1kHz, 1.87uH/10kHz, 1.74uH/100kHz
R: 0.027ohms/1kHz, 0.030ohms/10kHz, 0.080ohms/100kHz.
Clearly there is skin effect, but the DC resistance value is 100 times lower, so who the heck cares.
The inductance is lower and the capacitance higher than the Fidelium- which is also to be expected.

In my system, with the electrostatic loudspeakers, the 10AWG cable, or even better- the Mogami 2921- is a far more suitable cable than the Fidelium which is c. 50x the price.
It should be understood that the Fidelium cable is a perfectly fine cable. However, it looks like a moderate inductance, high temperature coefficient, high wattage, 2.5ohm thick film resistor, so unless your loudspeaker looks like a perfect 8ohm load over the audio band you can expect potentially extreme frequency variations for the amp - cable - speaker combination.
Hardly the "neutral over the entire audio band" element that the reviewers (who never seem to actually measure anything) write so gushingly about.

 

[HPMguy]

I always get a kick out of all the "science" around 6' cables. All the physical effects including wave guide and skin transmission are quite real, but essentially un-measurable in short, decent sized copper wires less than 12' long. Audio is essentially highly variable DC current (very rare to have single wavelength sustained signal except when testing, eh?) and all the high voltage, high frequency, etc effects mean absolutely nothing since the distance is well below a half wavelength of anything remotely audio range at the speed at which the signal is moving in the copper wires.

Different story if you are pushing a digital signal, or RF through the wires as a carrier, or going 1000' like you would in a big auditorium, etc, but for home use, most likely the fancy cables with weird shapes or dozens of braided wires will introduce more signal distortions that simple heavy copper multistrand.

My feeling is that the less change there is in the signal the better, and it's hard to beat plain 12 gauge copper multistrand at any length I would ever use.

 

[wyn palmer]

I always get a kick out of all the "science" around 6' cables. All the physical effects including wave guide and skin transmission are quite real, but essentially un-measurable in short, decent sized copper wires less than 12' long. Audio is essentially highly variable DC current (very rare to have single wavelength sustained signal except when testing, eh?) and all the high voltage, high frequency, etc effects mean absolutely nothing since the distance is well below a half wavelength of anything remotely audio range at the speed at which the signal is moving in the copper wires.

Different story if you are pushing a digital signal, or RF through the wires as a carrier, or going 1000' like you would in a big auditorium, etc, but for home use, most likely the fancy cables with weird shapes or dozens of braided wires will introduce more signal distortions that simple heavy copper multistrand.

My feeling is that the less change there is in the signal the better, and it's hard to beat plain 12 gauge copper multistrand at any length I would ever use.

The point is that the signal is, in general, NOT propagating in the copper wires. If it were, it would be really slow. It propagates outside the wires and between the wires in the electric and magnetic fields that are generated. This is true all the way down to DC. Maxwell's equations have no frequency bounds. The Poynting vector is what defines the flow of energy. This is true even in the case of a perfect conductor where the electric field in the conductor is explicitly zero.
Understanding this requires the use of partial differential equations and cross products and is not for the, well, uninitiated.
Multistrand, insulated, wire, can reduce losses due to skin effect, but overall, what is important from a loss perspective is the real part (the resistance) of the conductor at a given frequency, and transmission line theory accepts this- even transmission lines at 60Hz (power lines)- where skin effect actually is a problem.
I know that this is contrary to what most people believe, and indeed what is often taught in high school and even in college to some extent, but it is the case.
For circuit design in most cases, it is a convenient, and sufficiently accurate, approximation at LF.
I hadn't planned to do this- but just to illustrate the point:
https://web.mit.edu/6.013_book/www/chapter11/11.2.html

 

[UncleAng]

Green is the frequency response at the output of the amp. Blue is measured at the speaker terminals.
NO ADDITIONAL RESISTIVE ATTENUATOR WAS USED

I have mentioned in many posts that it is possible to make speaker wire and interconnects that will affect sound. But my argument has always been WHY! They're nothing but grossly overpriced tone controls and they don't make one's system better or more resolving, rather they simply degrade the linearity.... fools gold.

 

[Audiofreak71]

I have mentioned in many posts that it is possible to make speaker wire and interconnects that will affect sound. But my argument has always been WHY! They're nothing but grossly overpriced tone controls and they don't make one's system better or more resolving, rather they simply degrade the linearity.... fools gold.

Here we go smh


Audiofreak71

 

[wyn palmer]

I have mentioned in many posts that it is possible to make speaker wire and interconnects that will affect sound. But my argument has always been WHY! They're nothing but grossly overpriced tone controls and they don't make one's system better or more resolving, rather they simply degrade the linearity.... fools gold.

Certainly, they can affect the frequency response- that's obviously demonstrably true. However, I've never been able to measure one that affects the linearity- at least not in the accepted harmonic/intermodulation/many tone senses.
The problem is that reviewers, and often listeners, are not objective observers in the true sense, but make what they claim to be "objective assessments".
These assessments are, alas, often tainted with their expectations- the manufacturer claims some goofy mumbo-jumbo based benefit and the reviewers are immediately biased towards believing that claim when an audible (or sometimes not) difference is found.
That does not mean that the outcome is not better. As you wrote, sometimes the element simply causes a change in frequency response, or for amps a change in the harmonic structure, that the reviewer likes for whatever reason.
I consider myself to be a trained observer- based on many years of listening to diverse audio systems and being able to correctly diagnose differences and often correctly assign causes. To my ears, this set of cables changed both his and my system substantially, but differently. I know now why my system sounded so different- but I don't know why his sounded so different (although I can surmise) as I do not know the impedance characteristics of his speakers/amps.

In any case, at least this tends to explain why people claim that cables sound different.
The answer is- they do, and they can measure quite differently in different systems.

 

[NH-MAN]

In any case, at least this tends to explain why people claim that cables sound different.
The answer is- they do

I spent 2 months everyday testing different cable conductors from house wiring, just using the center conductor of a coax cable to heavy gauge fine strand wire and everything in the middle. They all sounded different; some it took a long time and it might have been tiny difference but might be that little something one needed. One type stayed on a half hour and was horrible. funning thing is its was the type probably used the most out in the wild.

I urge others to try the same, the progression became predictive, and it was not what most would think, to me.

find the conductor you like best then you should be able, if you feel the need to, spend some money on a good set made with the same type of conductor and have confidence you will like it.

 

[E-Stat]

R: 2.45ohms/100Hz, 2.452ohms/1kHz, 2.457ohms/10kHz, 2.464 ohms/100kHz.

As your frequency plot indicates, that level of R has a similar effect to using a high source impedance SET tube amp.

If your M-Ls share a similar Scream Machine Roller Coaster impedance curve as the Montis where the values double in the space of an octave, it is easy to understand how it would change the tonal balance in your system. I use tube amps, but fortunately, the speakers have a far tamer curve.

 

[wyn palmer]

As your frequency plot indicates, that level of R has a similar effect to using a high source impedance SET tube amp.

If your M-Ls share a similar Scream Machine Roller Coaster impedance curve as the Montis where the values double in the space of an octave, it is easy to understand how it would change the tonal balance in your system. I use tube amps, but fortunately, the speakers have a far tamer curve.

Yes, except the high source impedance SET amp also adds oodles and oodles of "lovely" distortion...

Yes, the ESL11As are similar to the Montis. They have an improved but essentially identical panel.

The Soundlabs are not so different. You need to look a bit closer at the measurements, methinks.

The Montis have beyond bass area impedance excursions of c. 18 ohms at c. 1kHz and c. 0.8 ohms at 20kHz. The Soundlabs (in max brilliance mode i.e. without the resistive HF attenuator, I believe- please correct me if I'm wrong) have equivalent peaks at c. 14 ohms at c. 1kHz and 0.4 ohms at 20kHz- consistent with a larger panel with higher film/stator spacings.

The local minimum after the bass region is at c. 300Hz for the Montis and is about 8 ohms- very similar to the Soundlabs.
Having impedances much higher than this (a consequence of having an active Bass driver) in the bass region has minimal effect. Higher impedances, in some sense, are better, as the sensitivity to series impedances becomes increasingly small. Small variations are easily compensated for in the frequency response control of the bass unit, so this is entirely a canard.

A conventional tube amp with output transformers and without significant levels (>> 3dB) of negative feedback would have extremely large variations in frequency response into this load. Of course, the >> 3dB negative feedback would have other effects- such as extending the harmonic distortion spectrum in undesirable ways.
With this cable the -3dB point with the Soundlabs driven from a near ideal amp (i.e. the AHB2s) would be at about 5kHz, and about 6KHz with the Montis/ESL11As (just as the measurement shows).

 

[wyn palmer]

I spent 2 months everyday testing different cable conductors from house wiring, just using the center conductor of a coax cable to heavy gauge fine strand wire and everything in the middle. They all sounded different; some it took a long time and it might have been tiny difference but might be that little something one needed. One type stayed on a half hour and was horrible. funning thing is its was the type probably used the most out in the wild.

I urge others to try the same, the progression became predictive, and it was not what most would think, to me.

find the conductor you like best then you should be able, if you feel the need to, spend some money on a good set made with the same type of conductor and have confidence you will like it.

I'm attempting to show the correlation of measurements with sound outcomes. This is not that. If you have measurements, please supply them. If not, this is simply another unsupportable audiophile opinion, and you know, everyone has one, they all have exactly the same value, and are out of place in this thread.

 

[E-Stat]

The Soundlabs (in max brilliance mode i.e. without the resistive HF attenuator, I believe- please correct me if I'm wrong) have equivalent peaks at c. 14 ohms at c. 1kHz and 0.4 ohms at 20kHz- consistent with a larger panel with higher film/stator spacings.

That's what the chart shows but never use the HF control at max. Just past 12:00.

The local minimum after the bass region is at c. 300Hz for the Montis and is about 8 ohms- very similar to the Soundlabs.

I refer to the huge swings in the midrange.

A conventional tube amp with output transformers and without significant levels (>> 3dB) of negative feedback would have extremely large variations in frequency response into this load. Of course, the >> 3dB negative feedback would have other effects- such as extending the harmonic distortion spectrum in undesirable ways.
With this cable the -3dB point with the Soundlabs driven from a near ideal amp (i.e. the AHB2s) would be at about 5kHz, and about 6KHz with the Montis/ESL11As (just as the measurement shows).

First of all, I would not choose a cable with such a high resistive value. The VTL amps employ about 15 db of feedback.

 

[NH-MAN]

I'm attempting to show the correlation of measurements with sound outcomes. This is not that. If you have measurements, please supply them. Of not, this is simply another unsupportable audiophile opinion, and you know, everyone has one, and they all have exactly the same value, and are out of place in this thread.

Excuse me I didn't think it was out of place to support what I quoted from you. For your testing to mean much it would also have to include all different types of conductors. If you know anyone that has spent 2 months every day listening to and confirming different types do sound different let me know. Measurements aside I still think people need to listen to different types. Then one could use your measurements to support what they heard.