How important are transports?

A good DAC will buffer the data stream it is receiving so that the timing from the transport is irrelevant. So the timing will be based on the clock in the DAC, and the assumption that the DAC knows the rate to play the data back at (which, in most cases, is present on the front panel of the DAC as an indicator light or timing readout...e.g. 44K, 48K, etc.).

The only room for error is the transmission of the data stream, which needs to move data at a fraction of the rate that computers routinely send (and receive) digital data (losslessly, I might add, over extremely inexpensive cables).

Steve N - I appreciate your perspective, but I'm guessing that you don't have your DAC, personal computer, and house fan all plugged in to the same power strip. My only point being that when evaluating audio components that are bad about creating electrical hash on the line (Transports), audible differences may be partly due to power quality differences seen by the rest of your system.

Here's what I know: the $30 CD Drive in my computer can read most CDs (except those that are heavily scratched) PERFECTLY (tested via checksums during the ripping process) at speeds up to 52x normal playback speed. If you don't think your audio-quality CD drive can read CDs at 1x playback speed, or some ridiculous liquid you apply to the surface of the CD will somehow make these perfectly read bits sound better, I've got some swamp land in Florida you should definitely think about investing in. :)

It is all about the DAC.


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Might be some solid truth  to this opinion. 
= Meaninga  good cd player that boasts a good DAC inside, might still be a  serious contender to the newest  DAC craze bandwagon everyone is jumping on.
I'm old school,= a  combo ina  high quality cd player suits me just fine.
I ck out the DAC in the cd player, if pics show high quality,  , then why go  for separates?

In asynchronous USB the transport is slaved to the clock of the DAC. The clock is all-important as good clocking is the only viable antidote for jitter. Nevertheless the quality of the USB implementation of the transport as well as of the DAC are paramount (garbage in-garbage out), in addition short cable with tight tolerance to USB specs matters greatly, too. In S/PDIF it‘s the originating clock of the transport, the quality and impedance match of the cable and the noise environment around your stereo that matter most.