Compatibility question regarding a Chord 2Qute and a PS Audio Perfectwave Transport


After much deliberation I've decided on a 2Qute DAC and have located a used one in good shape.
My transport is a PS Audio Perfectwave memory player. I didn't think much about the compatibility of these two units until just now, when I'm about to buy the 2Qute.
....Here's the issue:
The PS Audio transport output options are (in order of quality according to the company), I2S, S/PDIF via balanced XLR, Coax via RCA and the optical.
The 2Qute's inputs options are: USB, BNC Coax and TOSLink optical.

Here's my question: From my reading it seems the 2Qute does much better with a USB input (the only input that's galvanically isolated).  Some go so far as to say if they had to use only the coax input on the 2Qute, they wouldn't want this DAC.
While separately the PS Audio transport and 2Qute are great, combining them forces you to use the coax connections which, on both units, are sub optimal.
....So you have two units that are pretty decent on their own and them combine them and have to use the least SQ optimal output/input.
Am I looking at this correctly?
Is this combination self defeating?
Kind of bummed as I was getting myself pretty sold on the 2Qute.
Thanks.
--My speakers, amp and preamp are Magnepan 1.7's, Butler TDB 2250 and a Modwright.
andrew-benn
Regarding the coax cable, I contacted PS Audio and got the following reply.  I'm not including the authors name as I didn't mention I'd use his email in a post.
_________________________

Good morning,

Though a bit expensive, we really like Anti-cables.

Specifically, http://anticables.com/interconnects/digital-rca-interconnects#!/Level-3-2-Reference-Series-RCA-75-Ohm-Digital-Interconnect/p/14696953/category=3682629

Though a bit expensive, this COAX cable is brilliant. The length is less important, and it’s the 75 Ohms which is crucial.

Best,



Well, I’m not sure what to suggest regarding that cable. On the one hand I would of course consider a recommendation provided by PS Audio for a cable to be used with one of their products to be extremely persuasive. On the other hand I don’t see how a cable employing that kind of construction can maintain an accurate 75 ohm impedance, at frequencies extending far into the MHz (radio frequency) region (those frequencies being very important in the transmission of digital audio signals), and without significant variations in the impedance along its length.  Not to mention the lack of shielding.

BTW, I note that Anti-Cables only offers their digital interconnects in a length of 1.5 meters, and near the bottom of their web pages on those cables they reference the paper by Steve Nugent of Empirical Audio which explains the rationale for that length. That length should be viewed, IMO, as providing the best odds of being optimal (unless an extremely short length is practicable, such as 6 or 8 inches or so), but both technical considerations and anecdotal reports that can be found here and elsewhere suggest that it will not always be optimal. As I mentioned earlier what length will be optimal depends on signal risetimes and falltimes (the amount of time it takes for the signal to transition between its lower and higher voltage states, and vice versa), which is almost never specified, and several other component and cable dependent variables.

Good luck. Regards,
-- Al
andrew, much of my knowledge of digital cables was learned from Almarg and others on the forum. My background is in the analogue world of broadcast and studio recording. So digital came later.

It is a trial and error process, so buy from companies that offer a return policy.
I agree with Al's statement regarding the construction of Anticables. We need to hear from a user's experience with them.  
My first coax cable was a 1.5m Mogami for $30, not great, but it got my kit up and running.