I was in the same situation 6 months ago and my research lead me to the Bel Canto DAC rev 1.1 - the .1 is an power supply upgrade from the original. The BC DAC retails for 1300.00 and they can be acquired on A'gon used for 500-600 dollars. Do a google seach a read the reviews -the BC is an excellent performer
NOTE....which ever DAC you settle on be sure to pair it with a high performance digital cable. When I initially purchased my DAC, I bought a well reviewed budget digital cable and at the time though it was a good performer...that was before I auditioned a Transparent digial reference cable -the difference was night and day. I never would have imagined that swapping out 1 cable would make such a difference, but it does, at least with my setup the diferrence was audible.
Good luck!