Difference in sound between copper and silver digital cables?

@almarg - Al, thanks as always for you complete and thorough descriptions and reasonings.

Your point about... 

one "Wire Type" being optimal for 50, 75, and 110 applications.

It was the RCA connectors I was referring to as being suitable for those impedances and not the wire type. But I do understand that according to conventional wisdom,  the impedance of the RCA should match the cable - so I too, wondered how one connector could be used for all three impedances.

However. Keith Louie Eichman has been delving into the minutia of the science of cable and connector design for over 30 years and has far more knowledge than myself, so I have no reason not to believe his assertions about his RCA connectors. 

The only tools I have to test their performance is my ears and to me they sounded better in every way.

The geometry of my cables is a signal wire inside a helix coiled neutral wire and unfortunately I have no idea what the impedance of that cable might be.  But perhaps it is the cable geometry that is performing "the magic" here? 

My I first attempt at making a cable for SPDIF purposes used some wire from a piece of CAT6 Ethernet cable and Copper Harmony RCA's using the Helix geometry. The signal wire was a single CAT6 wire and the Helix neutral was a twisted pair.

My "point of reference" for the comparison was a commercially available 75 ohm 1 meter cable specifically designed for digital transfers from Van den Hul, that had the requisite 75 Ohm RCA's. This was a conventional Coax geometry.

The results even surprised myself - that simple little CAT6 cable provided significantly better performance than the Van den Hul product.

I do not claim that my Helix geometry, with the KLEI RCA's,  would work for any length of cable, since my interconnects, as tested, were only 3 ft long.

The set of cables I finally ended up keeping in my system were only 18 inches long. Which also seemed strange since, from what I have read on this forum,  a digital cable should be over a certain length in order to work at it's best..

But I did compare the 3ft to the 18 inch cable and found no difference

Others have tried my Helix design as a SPDIF interconnect on longer cables,up to 3 meters, and they claim to have had similar success. 

There are many out there that do not believe the claims I have made regarding the Helix Cables and the Harmony RCA's in my many postings on this forum. 

And - if I hadn't tried them for myself, perhaps I wouldn't believe those claims either.

But there are now dozens of people from around the world that have tried them and reported significant improvements in sound quality.
- So it is not just my ears that is hearing the improvement

Regards - Steve

Jorma digital gets rave reviews but at $1700 it's way out of my price range. What common or boutique brands with a balance of richness and detail can be had for ~$300? Notwithstanding the implementation, does silver coated copper give you the best of both?

I get "just try them," but, seriously, it would help to narrow the field.

@ pmboyd

Audio Envy Digital Cable fits your criteria easily and saves you $175; I compared against Black Cat Mk 2, Snake River Boomslang and Revelation and it beat them handily...

I prefer the sound of copper by a good margin but AE copper design is more transparent than several silver cables I tried but just more musical.


Wig

pmboyd, between the personal tastes of audiophiles and your preferences, no one here can direct you to the perfect choice. 

As a reviewer, I suggest you not only consider digital cables, but the companies that most impress you in terms of cabling. I have found that companies I enjoy speaker, power, etc. cabling also make favorable digital-related cables. Cable companies tend toward their house sound, and try to get their cables to have similar characteristics. So, if you like a particular company's power cords, speaker cables, etc. the odds are good you would be pleased by the USB. 

Failing that, a company with wide recognition for quality build and good to superior sound is Audioquest, with many models and price points. I vouch for there being discernible differences between models. 

I now use regularly Clarity Cable's Supernatural USB, which would be outside of your price category. However, the previous Natural USB may work for you.