"The sound from the headphone out, on the other hand, was decent, but un-inspiring . The sound was a little soft at both frequency extremes. It lacked deep bass weight, and the bass was a little light overall, although punch in the mid-bass was good. The fact that even the Denon D7000 seemed to lack a little bass weight versus what they produce normally was a little disappointing."
I think the sound of Headphone out is because of OPA2134, DMK use the OPA2134 in front of headphone amplifier circiut which is Lehmann design!
Like Rob said the DAC out is wonderful, so the AD797 is good, also Lehmann design is no problem of course, so I also think the "lacked deep bass weight" is because of OPA2134, Maybe we will do some test and replace a better OPA soon!
-- david gao
and please put four AD797BR instead of AR, they are well worth the very small price difference
it would also be nice to add a BNC S/PDIF input instead of RCA, and a 24/96 USB chip instead of 16/48...then I would die to buy it off your hands