Digital XLR vs. Analog XLR - Balanced Cables

Mmike84 - It all depend on the DAC. If you use asynchronous up-sampling DAC that rejects jitter like Benchmark it won't make much difference what cable you use. I built my RCA to BNC cable using 75 ohm Canare coax.

I am running a DCS purcel to a Delius. The Purcel upsamples to 24/192 ks/S, but the only cabling method that is capable of delivering this highest upsampling is by using a pair of XLR (AES/ebu) cables, each delivering 96 rates per cable, combined to deliver a total of 192 via the two cables - at least for the DCS equipment. The ideal cabl would be a 6" cable + the terminations.

I have plenty of spare balanced analog cables, but have not yet purchased a pair of balanced digital cables for this applicaiton.

The analog vs digital XLR cable construction, materials etc are not going to make any difference - if indeed there is any difference in construction. As to carrying digital signals are not going to introduce jitter with the cable. Other than compatibility with connectors, there is no benefit to using a balanced connector for transmission of digital signals - there would have to be an incredible amount of noise to corrupt the digital signal, and if there were, the effect would not be in the least bit subtle. There is benefit in balanced connections for analog signals - assuming, of course, that the connections are actually to balanced inputs.

Musicnoise - of course there is a difference in construction and materials. Digital cable geometry is tailored to deliver 110 Ohms characteristic impedance and therefore eliminate reflections. How reflections add up and corrupt edge of the signal (causing jitter) can be calculated using Bergeron diagrams. As for analog cables one of the most important factors is dielectric constant of isolation material. Lowest dielectric constant close to one of air=1 is obtained by using oversized tubes made of foamed teflon. Foamed teflon has even better (lower) dielectric constant than solid teflon while oversizing keeps wire inside away from dielectric. Another factor is purity of the metal - not important with digital cables but very important with analog. The best is very pure zero crystal copper or silver. Purity reaches 99.9999999% for copper (9N) and 99.99999% (7N) for the silver. Zero crystal process is simply forging metal into hot forms instead cold ones. Cooling very slow prevents formation of the crystals (impurities resides between crystals). Zero Crystal copper has just one or two crystals per foot while regular oxygen free copper has few thousands. On the top of this many cables have anti-vibration shields and some have even fluid inside. All this is important of course if you believe, like I do, that cables make a real and big difference. If you don't you can as well use lamp cord - saves a lot of money.

Kijanki-

You point out the parameters which are important for digital and those which are important for analog. However, none of these parameters are incompatible making it entirely possible for a single cable to be optimal for both.

As for anti-vibration shields and fluids, I will not bother to comment.

Kal