I'll answer this then go back through the thread.
I mainly use it for my full sized cans, DT880/250, Shure 440, and modded SR80s. It was the Beyer that really showed the advantage of having both in the line. Without the Asgard, the bass was less present and the highs tended to sound shrill.
Oh and my STX is dead quiet, no interference at all, but I think it's because I got an adequate power supply when I got it installed.
Edited by rroseperry - 12/15/11 at 10:06pm