Digital Cable Choice; how critical is it?

Jeffcott,
Although the Cyberlight mentioned above is fiberoptic it needs RCA or XLR connections on your transport and DAC. It sends and receives light signals at its terminations.

I really am a music guy & not a computer/techie guy. So, considering that the digital information that runs from the DAC to the Preamp is 1's & 0's or bits & bytes or whatever they are called; how critical is it to the sonic perfromance that I use an elaborate digital cable, as I have done with my analog interconnects?

Apart from clocking issues...I really can't see how it can make a difference. Either the bits all arrive or some of them don't.....you will soon know if some don't as you may get some nasty pops or clicks.

As for clocking.....a cable, being a passive device, physically cannot add "jitter". Length and electrical properties will of course modify the absolute timing and shape of the clock signal but a constant shift is NOT of concern, as audible jitter issues come from VARIATIONS in the clock signal between ticks. Furthermore, some jitter is not a problem provided it is small enough and random....i.e NOT influenced by some highly correlated influence such as oscillations in a power supply with bass response or induced correlated RF noise from somewhere.

Jitter is more component related than cabling. Changing from optical to SP/DIF might make a difference but the cause is most likely due to RF interference or the accuracy with which components either generate or interpret these two different signals.

If your clock signal is accurately re-clocked in the DAC (rather than a slave to the transport) then you have nothing to worry about (except your DAC)

....just my two cents.

My experience has been that most digital cables do sound different and that it's not necessarily a matter of cost. Please remember that a bit stream (0's and 1's) is NOT traveling down the cable, but an analog waveform with peaks and valleys that gets sampled and turned back into 0's and 1's. So anything that can effect an analog cable can effect a digital cable. In fact, some of the best digital cables I have heard (at least metal S/PDIF cables) are really analog cables at heart. So keep that thought in mind when auditioning cables. FWIW, the best performing S/PDIF cables I have heard are the Audio Note Pallas, the Locus Design Core, the Apogee Wyde Eye, and the Kondo Sounds Labs KSL-LP, most of which are terminated with RCA's (in my case).

"As for clocking.....a cable, being a passive device, physically cannot add "jitter". Length and electrical properties will of course modify the absolute timing and shape of the clock signal but a constant shift is NOT of concern, as audible jitter issues come from VARIATIONS in the clock signal between ticks."

Everyone thinks they are an expert. You are incorrect. Read this white-paper:

http://www.positive-feedback.com/Issue14/spdif.htm

Important aspects for a S/PDIF coax cable:

1) length
2) characteristic impedance
3) terminations
4) conductor sizes
5) geometry
6) metallurgy
7) dielectric materials

Steve N.
Empirical Audio

"Please remember that a bit stream (0's and 1's) is NOT traveling down the cable, but an analog waveform with peaks and valleys that gets sampled and turned back into 0's and 1's."

This is certainly true, however the analog nature alone of ALL signals is NOT the main reason why digital cables often sound different. This has specifically to do with digital circuits and how they treat the signal versus analog circuits.

Digital circuits detect transitions in signals and make decisions based on this. The detection of these transitions is not an absolute thing. There is uncertainly involved because of the imperfect voltage references, ground noise and voltage noise. Slow risetimes in the signal can increase the uncertainty, making it much worse. Reflections can superimpose on the signal shifting it in time.

Steve N.
Empirical Audio