Regular interconnect or digital?

Probably since it was designed specifically to transfer digital signals.

ozzy

yes, they are not identical...

+3

One of the biggest changes (the huge, like someone swapped the components to much higher grade) occurred when I swapped my first digital cable. I was absolutely sure I would not hear a difference.

High end interconnect manufactures make both with different construction.

Cable carrying digital signals has to have characteristic impedance matched to source output impedance and DACs input impedance (all three the same), otherwise there will be possible reflections on impedance boundaries.  Such reflection can produce time jitter of the signal that will result in added noise after D/A conversion.  Characteristic impedance for high frequency signals is roughly SQRT(L/C) of the cable (independent of length) and for unbalanced DAC connection is usually set at 75ohm (110ohm for balanced input).  Ideal cable would be at least 1.5m - even better 2m.  It is to make first reflection from the end of the cable miss edge of the signal without adding to it (distorting it).  It is possible, that your analog cable impedance is very close, but  chances of that are slim.  Digital cable doesn't have to be expensive since impedance match is most important (cheaper cable can be a better match).

The only case when cable doesn't matter is when it is extremely short (no reflections).  If you can make any cable shorter that 1 foot (6" would be even better), then you don't have to worry about impedance.  It is also possible that your DAC has strong jitter rejection and will sound the same (inaudible jitter).

+1 kijanki! I use a 2 meter 75ohm Monoprice between transport and DAC. No need to spend more!

So I need 1m cable to DAC.  Any recommendations?

There are so many choices. Depends on a budget for starters.

Here is one for sale on Audiogon site. I’m not the seller....just did a quick look for examples. Good name cable.

Cullen Cable True 75 Ohm 1 Meter Nitin Digital RCA Cable Made in the USA! | Digital | Atascadero, California 93422-5309 | Audiogon

@boxcarman   Not 1m, but 1.5-2m.   

Start of transition at the source creates possible reflection at the end of the cable (slight impedance mismatch) that comes back and adds to the this edge changing its shape.  In order to miss threshold point (middle of transition) total travel time (forth and back) has to be more than half of transition time.  Typical transition is about 25ns.  Half of it is 12.5ns equivelent to 2.5m total both ways resulting in min 1.25m one way (assuming 5ns/m propagation).  Of course it is all guessing since propagation time vary (is dielectric dependent), while transition time can also vary.  So this is wide guess, but it doesn't hurt to aim for longer cable.

@jasonbourne52   I just looked at Monoprice cables - seems like solid choice - inexpensive and well shielded.

Thanks, people, for your help.  I am checking them out.

Not knowing your equipment that makes it very hard. If you have audiophile equipment I definitely recommend Transparent. Cardas is a tad warm, which enhances most systems. DH Labs, good budget interconnects.

boxcarman:  technically, I'm sure that what's been said here is true but you asked about sound quality.  With regards to that only, you can certainly use a regular interconnect and get at-least comparable SQ.  When I purchased my first separate DAC in many years a couple years back, I used a Black Mountain pinnacle silver interconnect with RCA's on one end and XLR's on the other I had in the cable drawer.  The transport is a Bel Canto Cdt-3.  I was getting better sound with this combo than the Consonace Droplet 5.0 and Raysonic 228 I previously had.  Of course, I wanted a digital cable so I found an Acoustic Zen MC2 and gave that a try.  The Black Mountain interconnect was more vivid and precise.  There wasn't an area where I felt the AZ cable was better so I re-sold it and later tried a Neotech NEVD with Oyaide BNC and Xhadow RCA plugs.  It's 6 one way, half a dozen the other.  There are difference but really, they are equally good.  

Icherepkai,  I had to compare different cables and the most revealing sounds came from a medium priced Audioquest digital coax cable 1.5 meters.  Not just a small difference and now I am re-visiting all my old favorites [again].  Fun.

Hello boxcarman - Digital cables in my experience should be at least 1.25 -1.5 meters long and cable dressing is important. Keeping the cables from touching each other is key to best performance. I used a very good cable for a while on my Naim nDAC. TheCableCompany sells The Silverstar! mk II By Black Cat Cable. Great bass and smooth high frequencies. I had to move up to the Chord Company’s Signature Super ARAY Digital Coax to out play it. Not all coaxial cables sound the same, in my experience.

I own both Cullen and Signal Cable digital cables - 5’ in both cases.  Both are good but in my system I prefer the Signal Cable which at $64 is a bargain.