Best headphone amp for new Senn 650's

The Cary CAD300SEI is a killer headphone amp... definitely overkill on the high end of the scale $-wise, but excellent sounding. it and Senn 600s Kicked the butt of a Stax set up I had on audition for a while. Doubles as a great little integrated for small to medium room systems with speakers of 87db/1wm sensitivity or better. Add a CD player and it's a two-box system.

-Ed

If you like tubes, try the Earmax Pro. I've been very satisfied with my Pro/Senn 600s. The tube combination I've found to my liking is Telefunken 12AT7 and Bugle Boy 6DJ8's. I could listen for hours (and do)!

Try the Musical Fidelity V3 . It is amazing! and under $ 400.00

Just my $.02 here, but since you didn't limit the price, I agree with Ed and Jim that the Cary SEI is nice. I disagree that the Earmax is next best though. I had the Earmax and it was (in my tastes and in my system) not any better that the headphone jack on my Pioner Elite CD recorder. I also have a Headroom Cosmic which easily bested the Earmax. My main headphone rig, like the Cary SEI, doubles as a very nice SET integrated - the Moth Audio SI-2A3. If you like a typical warmer but clean and detailed SET tube sound, the Moth is fabulous. If you like a little more slam then the Cosmic has more of a solid state sound and is tighter in the bass with nice dynamics.

I also had the first version of the ASL MG-Head amp and, although I liked the sound, it cannot drive the Senns to any decent volume and the Moth is much more dynamic, with better detail and focus.

If you like the tube sound, I recommend checking out the ASL OTL32 headamp/preamp or the ASL Twinhead headamp/pre or the RKV. If you want solid state, I think you'd be hard pressed to find anything better than a PPA amp, regardless of price. Several head-fi memebers said they heard a PPA amp with the HD650 at a meet and it blew away the Headroom Blockhead. So you could go with a PPA and save quite a bit of money. There are tons of amps out there, so be careful and don't lose your head over this. BTW I have the HD580 with MG Head OTL and I think it is a wonderful combo.