Beyerdynamics T70
Audeze LCD-2
Audeze LCD-3
Onkyo TX-SR805

“Then I compared both Burson amps with the my Onkyo TX-SR805 receiver. Its headphone jack is fine, but sounds drab and lifeless after you get used to something better. If you have already invested in a great set of headphones you really should consider moving up to a dedicated headphone amp, like the Burson Soloist.”

Full Review Here: http://news.cnet.com/8301-13645_3-57508400-47/the-burson-soloist-will-make-your-headphones-sound-better-than-ever/