Pros: Controlled bass, solid soundstage, excellent headphone amp, silent operation, versatile
Cons: whimpy power supply, low quality potentiometers, slightly weak midrange presence
I've written a fair amount about this audio interface in other forums, especially on the ComputerAudiophile site, so I'll summarize here. I originally purchased this interface as an upgrade to my Behringer UCA202 for making live direrct to two track recordings of piano recitals and school band concerts (using Rode NT5 mics). Unfortunately, I didn't get much use out of the interface during my first year of ownership due to firmware issues (lots of dropouts and popping during recording and especially during playback). I finally got around to giving the February, 2008 firmware update a try in fall of 2008, and that made all of the difference for me. I'm currently running the interface with the beta v1.4 drivers on Windows XP (sp3, 32-bit) and Windows 7 Ultimate 64-bit with great results so far.
While I do still use the interface for live recordings (in fact, I'll be using it to create one this week), it now spends most of its time as the primary source in my main music system. Like many here, I use Mediamonkey to stream FLAC files via USB to the E-MU. The outputs of the E-MU are connected to 1/4" TS/RCA adapters connected to LAT International IC-200 cables (which were more expensive than the E-MU 0404 USB itself!) which run to an Emotiva UMC-1 pre/pro in "Direct" mode. That feeds a McCormack DNA-1 power amp which drives Legacy Audio FOCUS SE loudspeakers. Instead of the wimpy stock wall wart, I'm using a Regal Electronics R1JG-5500 linear regulated power supply, which seems to improve dynamics and bass slam. Sound with the stock supply was somewhat lean by comparison.
Compared to my Denon DVD-2930CI SACD/DVD-Audio player, the E-MU with upgraded power supply provides more controlled bass with lifelike impact and dynamics. The soundstage has the same width as the Denon but more depth and detail, especially when playing high resolution sources. Separation of individual instruments and musical lines is better and there is more air around each contribution to the mix. That said, the Denon seems to be slightly more comfortable to listen to for extended periods of time. I have not decided if my tendency to skip around more with the E-MU is due to the fact that I have complete random access to my entire audio collection (via Mediamonkey) vs. spinning one optical disc at a time in the Denon, or if there is something about the sound of the E-MU that's not quite perfect. Direct comparisons, switching back and forth, always tell me that the E-MU is better in just about every way (and the Denon was a $650 unit when I bought it), but sometimes the head and heart don't always agree.
I had the opportunity to audition my E-MU along with a friends M-Audio ProFire 610 this weekend through Aerial Accoustics 10T loudspeakers. Neither interface was perfect but both offer amazing audio pleasure and value for money. In his system, the E-MU rendered bass with exemplary control, neutrality, and authority while the M-Audio interface produced mushy, poorly controlled bass with less impact. However, midrange presense and detail were clearly better in his system through the M-Audio. Unfortunately, we didn't have two sets of identical interconnects, so the E-MU may have been at a slight dissadvantage, but regardless, both interfaces were a delight to listen to in their own way.
I hope to audition the E-MU with an Emotiva XDA-1 DAC soon. I'd also welcome the opportunity to compare it directly with a Benchmark DAC1 since this DAC is so popular in the ~$1k price range. Because technology changes so fast, spending much more than $1k on a DAC is hard to justify, at least for me. For now, I am delighted with the little E-MU 0404 USB and will continue to use it until I find something for less than $1k that's a lot better.