For sale I have an Anedio D2 Dac/Amp. This is one of the best DACs I've ever heard and the amp is even better than I anticipated. It powered all of my headphones extremely well. It would even push the HE-6s, though not to the levels of a speaker amp. I used it mainly with USB and it really did shine.
Comes with power cord and RCA interconnects.
Price includes shipping. Add 3% for paypal, or gift.