What's the best USB audio interface?

The Edirol UA-1A will do the job for you,
doing the D/A conversion as well.
But the UA-1D passes SPDiF/Toslink
to your DAC and I'll bet your DAC is
better than the one in the UA-1A.
Go for the UA-1D.

Interim Summary.

Thanks to all the a-goners who have breathed life into this
thread. Your input has been very helpful and is certainly greatly appreciated.

Some URL's for quick reference
(for anyone who is, as I was, totally lost):

One user's experience with the Roland UA-1D
http://www.andrewkilpatrick.org/projects/spdif/reviews/edirol_ua1d/

Successor? of the UA 30, UA 3D
http://www.edirol.com/products/info/ua3d.html

Motu 828 is an (expensive) USB audio interface
http://www.motu.com/english/motuaudio/global/body.html

A short review of the Roland / Edirol UA 30
http://www.techtv.com/audiofile/story/0,23008,3321060,00.html

Audiotrak (EgoSys) OPTOPlay, simple feature-set similar to the UA-1D
http://www.audiotrak.net/eng/optoplay.html
Maya 7.1 USB (overkill) -- http://www.audiotrak.net/eng/maya71u.html

ESI U24 waveterminal (esi-pro.com, ESI=formerly Ego Systems or EgoSys)
http://www.homerecordingmag.com/review3.asp (truncated review)

Ballpark price points:
USD 0.1k - Sonica; UA-1D; Optoplay;
0.15k - UA 30, used; Stereo-Link 1200 ($169: 220-240V internat'l version);
0.25k - ESI U24 Waveterminal;
0.8k - Motu 828 (firewire 2xXLR or 1/8" to RCA);
1k+ - Apogee Mini-DAC (shipped Mar2003, price est. mini-me based);

Possible strategies:
- kiss (keep it simple,stupid): Optoplay; UA-1D; Sonica;
- added flexibility: UA 30; UA 3D;
- better build: ESI U24 waveterminal;
- consumer convenience: stereo-link;
- overkill: 828; mini-dac;

For the moment it seems that the k.i.s.s. strategy wd be most reasonable. Information/3rd party reviews/tests on the ESI/Egosys/Audiotrak products is harder to locate (they've got good mentions elsewhere in the forums tho). There are some unresolved issues: e.g. compatibility with the OS. Ultimately, I'd like to get this setup running under some flavor/color of Unix -- Linux or a version of BSD -- with a low-key text-based GUI (vs. some color and graphics-intensive one in windows) controlling the whole thing. There is some learning curve. The contributions are encouraging.

I have the M-Audio Sonica. I like it a lot. It runs to a Monarchy DIP and then a ART DI/O DAC and then to my preamp. Music sounds good.

The Sonica requires Windows XP or 2000.

John

The m-audio description of the sonica mentions Win XP, 2000 but also Apple's OS X. But I wonder whether the sonica might still work with linux kernel 2.4 and above which has USB support - OS X is Unix-based as far as I know. I think it may be to some degree widespread that USB devices can be used with Un*x, even if this OS is not officially supported. May be just wishful thinking tho.

I am using an older computer as my music server. I am currently using a AMD K6 522 mHZ CPU with 256 MB SDRAM to host about 4000 mp3s (legal downloads from www.emusic.com) and a bunch of live shows in the lossless SHN format. I have several older used hard drives and a PCI IDE controller card which controls the three hard drives and the one CD-ROM (a generic Creative 24x). The computer is also networked to a faster CPU with even more music (more SHN files). I have a generic 2 MB video card. My OS is WinXP Pro. I don't have any other hardware (no PCI soundcard or modem). This computer is basically a bunch of old parts that I had laying around.

My media player is Foobar which uses the kernel streaming to move the music out the USB port. Foobar sounds much better than the other media players I have tried (WinAmp, FreeAmp, MusicMatch, MS Media Player) and uses far less resources. It only works with the XP/NT. Foobar also has fewer features than most media players. It is a slim player and not full of bloat like many of the others.

Attached is a review of the Sonica from ExtremeTech:
http://www.extremetech.com/article2/0,3973,662385,00.asp

Also, I have not found drivers for the Sonica except for NT/XP drivers.

Hope this helps.

John