This is amazing:http://www.amazon.com/dp/B0093KZWRE/ref ... 1_ST1_dp_1
And real cheap. I have it connected to my main system and it is a fine DAC apart from everything else.
I am running a factory tweaked Sonic Frontiers Signature Pre Amp, I knew the founders, into SFM 75 Monoblocks feeding original B&W Matrix 1 speakers with rebuilt crossovers, amazingly the originals were crap. Biwired with Tara Time and Space speaker wire. I have not rolled that out in a long time.
Others too have praised this little gem, the consensus appearing to be that it's about equal to stuff 10 times it's price. Seems reasonable to me and I have not yet hooked up the SPDIF which is supposed to be audibly better.
Good stuff in it too:
The headphones I have, cheap AKGs, are nowhere near my system so it's hard for me to judge the headphone amp.