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
The headphone jacks on the Manley 300B preamp and the Cary 300sei integrated amp are also very good.
I currently use Consonance M20 with my AKG K701. I enjoy that heavy headphone amp a lot, but would still prefere something more versatile like Musical Fidelity X10 V8 with input, bypass and USB-Dac.
I use my speakers for parties only and only headphones deliver me a quality listening sessions!
The price-no-object headphone device is Grace Design M902 which is also a balanced preamp, highest resolution universal DAC and state of the art headphone amp.
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Best headphone I have heard (vs. Senn 650, AKG 701, Stax Lambda Pro)is the AKG K1000. If you go that way, they need to be driven from the speaker outs from about a 5 wpc or better amp. This puts many SET integrateds into the picture. Right now I am using a Glow Amp 1 which has USB DAC or RCA line level inputs. The K1000s have very quirky ergonomics; about $1K on the used market (no longer made) but are cleary the best I have heard.