I've been considering this myself...though I haven't tried one, you may want to look into the Tube Audio Design's TADAC. I have Paul's TAD150 pre & it's very nice...he has a good reputation. Paul has a try the DAC for 20 days & return it ($45 restocking) if it doesn't float you boat offer.
Pls recommend tube DAC
I'm looking for a good, inexpensive tube DAC. How much is inexpensive ? Around five hundred bucks. Then again, if this tube DAC is that special i can go up accordingly. Thanks for your advice.