Best $300 or less Tube Headphone Amp


I have a pair of Sennheiser HD600 cans and I'm looking for a $300 or less tube headphone amp that will work well with them. Thanks!
oregon3
Have you checked out www.head-fi.org? They sponsor a set of forums dedicated to headphone users, including a forum on headphone amplifiers. With a little searching you'll probably be able to get some specific recommendations for your particular headphones. Good luck.
ASL MGhead. I use it with my senn hd600, and it has good synergy.

Also, the high gain grado RA-1 actually has a little more detail but you lose some of the tube qualities.