Ya know, I've been thinking about converters recently. I don't have a top of the line D/A converter, and so it occurs to me that I can't be sure of "converter tests" I find on the internet, because when I play the files back through my system, my own D/A is probably skewing the results. Seems like the only way to reliably hear the effects of a converter is to have a high quality analog system that can play direct to your monitors, listen to it, then run it through your converter and listen to that - realizing that even in this case, there's *no way you can hear just the A/D* since you can't hear "D" - it has to go through at least one more conversion - D/A - before you can hear it. I guess you can compare graphical representations of converted wave forms, for whatever that's worth.
Anyhoo, I hear a lot of folks talk about how the various chips that perform the conversion are not far from one another in terms of quality, and that the quality deltas are so small that most of us would never care - I can believe that (but, again, obtaining and evaluating audio evidence of that is just not within reach).
But one thing I learned when Black Lion Audio worked on my MOTU Traveler is that there's more going on in a converter than just the chip - by that I mean just the analog components that work to get the signal off the wire and feed it to the chip in the case of A/D, and take it from the chip and put it back on the wire in the case of D/A - if those things (resistors, capacitors, etc.) introduce crappiness, then the practical quality of the conversion is worsened. BLA worked on that aspect of my Traveler, and I swear it sounded noticeably better afterward. You'll have to trust me on that - *because, in my opinion, there's no way for me to prove it over the internet*, for the reasons I mentioned above.
2005 was a good year.