Looking for a great tube headphone amp

Don't rule out the MELOS SHA-1...

I'll cast my vote for the ASL MG Head amp driving the Sennheiser HD600. I don't find it excessively tubey, very good bass, excellent dynamics and revealing without being brittle, an excellent combination!

I second the Melos SHA1 or its relatives. Sounds very, very good and reasonable from a tube rolling standpoint. You get a pretty nice pre-amp in the bargain, too. I am a dedicated Stax man, but appreciate the Melos, also.

Interesting to see that I'm the only one here who didn't find the ASL MG Head DT to work to his satisfaction with the HD600's, hearing a consistent sonic signature across all of my sources that comparision revealed was endemic to the amp. For the record, since some of the above folks mentioned this, I did invest in a new pair of JJ EL-84's and burned them in well, but didn't find the sound a whole lot improved. I returned the unit for a refund, but I currently have no use for the upgraded tubes, which have a long life ahead of them...offers, anyone?

Before you buy a tube headphone amp consider the GRACE 901.This is the amp used by the best engineers extant and what they final master what you wind up listening to yourself.At 1300 retail, not cheap but when I am listening to my HD 600'S sourced through the audio aero mk1 with the GRACE I feel graced.