Audiophile USB to PCM


I have an excellent upsampler and dac (dCS Purcell/Delius) and am looking for the very best USB to PCM conversion. So far, I've tried SlimDevices Squeezebox, and Xitel Pro Hi-Fi link.

Both are very good, but I was wondering if there are any other options I should be considering. Both the Sutherland USB Preamp and the Wavelength USB Dac convert to analog. I'd like something of similar quality that stops short of the digital to analog conversion so that I can let the dCS gear do that.

Any suggestions would be appreciated.

harry
hbrandt
Rsbeck, the apogee is a fine DAC, from all I've heard. But, I don't think it is in the same league as the Hbrandt's $14K dCS stack. While apogee is forward thinking in incorporating USB into the box, there are very high end DACs that don't--the U24 and M-Audio pieces work well in those applications. You may want to try a Waveterminal for your application. I didn't think the stock Transit/Sonica family sounded that great compared to some other pieces, but they still sounded pretty darn good with decent source material, so I still don't understand why you had bad results. Maybe a bad unit?

As an oddball sidenote, I had my g/f close her eyes and played some short clips from the same song through iTunes. One an uncompressed .wav file ripped with EAC. The other was a derivative mp3 created with LAME using the "alt preset extreme" VBR setting--a *very* high quality mp3 that I've heard many say is overkill. Yet, she was able to clearly ID the .wav as "sounding fuller" and "better"--notwithstanding the fact that she has significant hearing loss.
Edesilva, I've had the exact same experience too in comparing VBR mp3 and a .wav out of an M-Audio Firewire Audiophile. Interestingly enough, if I convert the VBR mp3 and burn it to disc (I use the program burrrn. It's free, uses LAME to decode and does gapless burning of tracks), and burn the .wav (or just play the original cd) the difference between the two decreases dramatically (though I still notice it on most tracks). I've noticed this on other setups as well. Something's going on which I haven't figured out yet. I've tried Winamp and Foobar and have had the same results.
When you say you "convert the VBR mp3," do you mean turn it back into a .wav? Hmm. If that is what you meant, one possible explanation may be that the CPU has to do more processing on an mp3 and that somehow causes audible changes--i.e., its "easier" for the computer to play back a .wav? Strange. But, it does take some serious time to create mp3s, so maybe...
Yes, I mean convert mp3 to wav. I can't imagine it has anything to do with processing power. If my ipod can do it at all then my 3.0ghz machine should be doing it effortlessly. One thing I haven't bothered to do is a .wav on the hdd versus the same track on cd.
This is a great conversation and I'd bet it has been read by many looking for the right solution for PC SPDIF out.

Ultraviolet/Rsbeck's gon posts about the M-Audio Audiophile (USB, firewire) have made me skeptical of the unit before it arrives on Wednesday. The PC digital out is the last piece in my system and has been the most difficult to choose. Here are the most important things I have gathered:

1. The M-Audio Audiophile USB using SPDIF digital to external DAC at least sounds different (and reportedly worse) than other units such as the Waveterminal U24. I haven't found any direct comparisons with RME or SoundDeluxe. All I've read about those are they are recommended. You can get a used RME card with SPDIF for about the same price as a USB Audiophile.

2. The piece matters! I'm going to re-post Dmitrydr's comment. If true, this seems to be the most important thing to know about buying SPDIF out for a PC: "you'll need a box (where jitter will inevitably appear) that accepts USB data flow, and converts it to SPDIF, i.e. performs quality reclocking, etc. Here, if this box is treated just as part of the audio system, and connected with short good SPDIF cable to the DAC, there should be less jitter then from a normal CD player. However, for low jitter this box must have audiophile-grade power supply, oscillator, and other parts, so its price level must be expected somewhere near any other audiophile DAC. Cheap solutions must introduce lots of jitter, making the whole idea nonsense."

3. The Waveterminal U24 is capable of not re-sampling 44.1 CD audio which may account for its truer sound (but no one seems to know for sure).

Oh, and Hbrandt -- you got me interested in this reclocking business with the Apogee Big Ben comments. Please convince me not to spend another $1k on it or I probably will ;-)