I don't find this reassuring.
I know all the reasons why putting the CD transport in with the DAC makes it easier to pull out a jitter free stream. I know that using a wordclock output from the DAC helps overcome the limitations of the spdif standard. Somewhere back at the beginning of this thread (
see post #166) John spoke about the MDAC (and therefore I would assume and hope, also the QDAC) having an external clock loop to improve the jitter of external spdif devices
But the CD counterparts
are bit perfect, and so 25 years after the creation of the CD digital standard and with the amount of silicon available at low cost ... I expect better
So, referring back to Dominic's comments in
post #250, I fully acknowledge that "the way to get the best results (jitter rejection) is not having to perform any". But despite Dominic's comment in that "There is no perfect jitter rejection in this world"...
on the basis that in high quality audio reproduction there is no limitation on time delay within the audio decoding process (this isn't HT and we don't need to sync image and sound), I can't see why data can't be pulled in and buffered and then clocked out in a perfectly stable, controlled and 'jitter-free' way. I do understand that this will/may introduce further circuit design and clocking problems and tasks.
None of this is intended as negative comments on what has been endeavoured and appears to have been achieved in the current designs - I'm waiting for the QDAC as it appears to be just the digital/analogue preamp I'm looking for. Prior to this (thread) I'd been eyeing up the Buffalo and Wyred4Sound offerings, but John & Dominic's designs do seem to genuinely advance the state of the art at a surprisingly low price point.
However, I think that something more universal should be possible for the 'digital source era'
They really are just 0s and 1s
Chris