I hope it's ok to take someone elses statement and quote it.
For what it's worth, here's a quote about the ATH-W5000...
"But, I just fired up a flamenco cd of Ojos de Brujos tonight, through my now fav Audio Technica W-5000 headphones, and there's another eye (ear) opening session going on here! I've not turned off the Solo Green, had a signal passing through it all this time with a streaming on line radio station, through a soundcard. I wish you all could hear the AT's through this amp. I've got a pair of the AKG 701's also, but there's no comparison in every conceivalble area of reproduction. The AT's are, to me, akin to Stax with bass. Incredibly fast, detailed and musical. The Solo Green is improving, still. An amazing statement, but I can't deny what I'm hearing. I'm just floored, here. So much hitting power, more depth, no harshness at all. This set up is completely flat, no tone controls, no dsp, no nuttin. I'm learning to keep a signal going thru this amp. It has just continued to get better and better."