warm digital cable

01-26-12: Mapman
I'd question whether any digital cable has a signature sound that is evident in general from application to application....

I second Mapman's comment. Given reasonably good quality, I see no reason to expect a high degree of correlation between the effects of a given cable on jitter in one system, and its effects on jitter in another system. And many reasons to expect a low degree of correlation. The same even applies to the effects of a given cable on jitter in one system, and the effects of a different length of the same cable type in the same system.

An example: Impedance mismatches can be a significant contributor to jitter. No impedance match is perfect. If the input or output impedance of a component that is being connected is inaccurate to some degree, relative to the 75 ohm ideal for S/PDIF, then a cable whose impedance is SIMILARLY inaccurate will provide a better impedance match to that component than one that is more accurate.

The other major contributor to jitter that can be affected by the cable is noise, that is either "picked up" by the cable, or that results from ground loop effects between the components that are being connected. In general, a shorter cable length will minimize both of those effects. However, a shorter cable length will often worsen the effects of impedance mismatches, unless the cable is very short (see this paper). Whether noise-induced jitter or jitter than results from impedance mismatches will be a more significant issue in a given system cannot generally be predicted.

Putting it more generally, the effects of a given cable on jitter are dependent on a complex and largely unpredictable set of relationships and interactions between its parameters, including length, impedance accuracy, shielding effectiveness, shield resistance, propagation velocity, etc., and the technical characteristics of what it is connecting, including signal risetimes and falltimes, impedance accuracy, jitter rejection capability, ground loop susceptibility, etc.

My suggestion to the OP is simply that you try a variety of different cables at different price points, and make your own choice.

Regards,
-- Al

i would think that parts, e.g., dieelectric, wire type, geometry, connectors, etc., should affect digital as well as analog.

i believe i could ascertain the difference between a digital cable made of silver and one made of copper.

MT,

You might hear a difference between two cables in any particular system but as Al points out, the results would likely not be reproducable consistently from system to system due to different jitter factors. So it does not seem likely that one could consistently attribute a particular sound with a particular digital cable.

My DAC reclocks things so jitter seems to be a non issue, and I have to say (really...I have to say it) that among all the cable changes and upgrades over the years, the S/PDIF upgrade from a basic VDMxr to the beautifully made Audioquest silver VDM 5 has made the least obvious improvement. Still, it SEEMS better...according to advertising spiel it should be better...and that's enough for me! Nobody wants to sit there listening to beautiful music thinking their digital cable might not be letting 100% of the beauty through. Still, bad digital recordings still sound bad, but I can listen the LP instead in some cases so that's okay.

When I ugraded from a generic digital coax cable to a K-Works Goldenheart digital cable, to my surprise, I noticed improvments in many areas, timbre, soundstage, noise floor, and more, but the overall frequency balance of my digital playback chain was not noticeably affected. So I would agree with Mapman.