Icon, S-1 & W-1 all in red color being driven by a stock Mac Mini (new version) pushing out Apple Lossless files. Need to raise the speakers up a bit, but other than that pretty flawless. I've also been using the Icon with both my Senheiser HD-600s and my Grado SR-200s. On opposite ends of the impedance scale but both work pretty well. I've also tried the Nuforce UF-30s, but they really don't stand up to the more expensive sets of headphones so I might sell those.