I'm starting this thread since it appears there are few threads on the topic of external soundcards currently.

From the http://www.pcavtech.com/soundcards/compare/ one can find a few qualified opinions on what a good soundcard is, but I would guess the most important aspect is to get it OUT of the computer (and shielded like there's no tomorrow).

So what are the experiences / opinions of the users on this forum?

I'm indulging myself in a single *bump* -

Hasn't anybody considered the interference from the computer as a noise-factor in a soundcard?
Are there really that few external soundcards?

Take a look at http://www.pcavtech.com

All soundcards analyzed at there are internal. The best ones (LynxTwo, CardDeluxe) have better noise & interference performance than most external DACs. BTW, there are some relatively old external DACs analyzed at there, so you can compare.

As yoi will see, noise & interference inside a computer is not a big issue if good engineering practice is used.

I think that balanced connections is more of a requisite when you want to achieve ultra-low noise levels.