Best Headphones & Amp---Opinions Please


I have a B&W / Lexicon centered high-end system. Just discovered the joy of listening to headphones. Have the Senn 650's with an upgraded 15 foot Cardas cable (no headphone amp) connected directly to my Onkyo 905 receiver. I would like to "push the envelope" in this area by upgrading to whatever my fellow aduiogoner's may suggest.

I would like opinion on the best equipment available. Cost is not a major consideration, but, I would rather not spend considerably more just for a 5 to 10% improvement--in other words---the most bang for the bucks.

Thanks in advance for your assistance--Dave
djones1915
Really appreciate all the great suggestions---Audiogoner's are simply the BEST! I only wish I had more specific knowledge I could share---I do what I can though.

Thanks again---Dave
I'll throw a couple ideas out there:

Ultrasone ED9 (used, out of production)
Ultrasone ED8
Sennheiser HD800's
Grado PS1000's

Those are my top four, relatively "affordable" cans.

As far as an amp goes, look at:

Trafomatic Experience Head One
The Woo's mentioned above
TTVJ 307A
PS Audio GCHA (I think they are out of production)
Headroom BUDA

Or...just get a Stax SR7-007 MKII and a Stax SRM-007tII and be happy.

Disclaimer--the only thing I offer for sale out of the above is the PS Audio, the rest I do not.

Peace,

Lee
Argh, one more, although I haven't heard it yet:

Red Wine Audio Isabellina

But, given Vinnie's past products, I am sure it is a great amp.
I'm not a headphone guy, but then I heard the Sennheiser HD800 playing just through an ipod, and now I want a set. Too bad the wait is so long to get a pair. They are being hand built in Germany in a cleanroom, and are way backordered.