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
I'm using an M audio Firewire Audiophile. It sounds quite good, but it has some quirky volume problems. They are supposed to address this in a future firmware upgrade, but until they do that, I can not recommend it.
Yes, I'm using the Mini-Dac as a DAC. I'm running USB from the Mac G4 laptop to the Apogee, then balanced XLR interconnects to a pair of Mackie HR824's --- I'm pretty astounded at the quality. I don't know that you need to convert the digital signal from your laptop to PCM in order to run it with your dCS gear. I could be wrong, but I believe you just need to keep it in digital since your dCS gear probably doesn't have a USB input, you need something between your laptop and dCS, something to connect them while keeping the signal in digital. I tried that with an input of a Proceed AVP2 so I could use the DAC in the Proceed. For some reason, it didn't sound that good. Only thing I can figure is that something in the M-Audio piece was degrading the signal somehow. Everything sounded time smeared. I'm going to guess that you could use the Apogee similarly and it would sound way better. I know the Apogee has a better clock/buffer which helps eliminate jitter, so maybe the signal was getting smeared by going through the M-Audio piece even though I didn't use it for DA conversion. When I get some time, I will experiment with the Apogee, connecting to the laptop with USB and taking an SPDiF out of the Apogee to the digital input of the Proceed and see if there's a huge improvement, as I expect, over the M-Audio piece. There may be a less expensive piece that will handle the transer and keep the signal in digital while eliminating jitter and smear for less money -- if there is, I'd like to know about it. In the meantime, I can tell you that the Apogee sounds great in my application.
Here is something that will take a USB input from your computer and convert it to toslink or SPDiF without performing DA conversion for $79 ----

http://www.computersandmusic.com/xcgi/SoftCart.exe/store1/edirol/ua1a.html?L+mystore1+urub1816+1088598294
Oops -- forget that one -- didn't notice that it is the opposite of what I thought. It is for sending digital input INTO your computer using the USB port. Sorry 'bout that. That's what I get for posting before I've had coffee!
No problemo Rsbeck!!! Edirol DOES make one that converts usb to pcm. As does M-audio, Xitel, Waveterminal, and several others. I'm just trying to find which one is the best.

harry