I have tried to only comment on those products that I have experience with. I only use Apple Powerbook, G4, and G5 computers.
My standard was to compare to a CD tranport on my system (McIntosh MCD 205 transport, McIntosh 1201s into XRT-28s). I compared by having a friend switch instantly back and forth between the CDP and the computer system playing the same music. Note that I could not switch quickly between the DACs so my comparisons are mostly with the CDP. I have tried the following USB devices, DACs, etc.
USB to M-Audio Transit into Monarchy DIP/DAC - did not begin to compare to CDP
USB to Transit to McIntosh MDA 1000 DAC - did not begin to compare to CDP
USB to Apogee Mini DAC - Sounded better than CDP, maybe just a bit tiring
USB to Waveterminal into MDA 1000 DAC- Sounded better than CDP
USB to Edirol UA-25 into MDA 1000 DAC - Sounded better than CDP
Apple G5 optical to MDA 1000 sounds better than CDP
The Mini DAC sounds really, really fantastic. It is not an upsampling DAC. The MDA 1000 upsamples to 768kHz. The two sound very different, all I can really say is that I am now listening to the MDA 1000 almost exclusively. The Mini DAC might be just a bit "digital" sounding.
I did not listen to the DACs on the Waveterminal or the UA-25.
Further comments:
I would probably end up electrocuting myself if I opened up the Waveterminal, so I am not your guy there. The Waveterminal is $240. The UA-25 has additional drivers, but still sounds great on the Mac. I find the iTunes software virtually flawless, so I have not looked for any alternative. I think that if you want to upsample, it should be done in hardware.
