I also have the Quicksilver Headphone amp. It is awesome, built like every other piece of Quicksilver gear....like a tank. It is high quality and sounds great with any impedance phone. Its killer for the $$$ I had mine built with a chrome transformer cover like my Mid Monos.
Headphone amp?
I would like to add high quality headphones to my system, which consists of a Pass Labs XA30.8 and XP-20 preamp, and SoundScience Music Vault plus speakers. Do I need a headset amp or is there some other way to use say, a pair of HD800s phones? I could in a pinch plug in to my CD player but I doubt it would be as good my amp/preamp. What would the cognoscenti suggest?