[marillion64]

I had both the K601 and the HD595 and sold both of 'em.I found the bass of the 595 kind of dirty and muddy compared to the bass of the HD 650 and I didn't like the K601 (I only liked the beautiful soundstage) but I haven't tried the K701 yet. To me the more you spend (on those brands...) the more you get...

 

[Foe-hammer]

First impressions (pre burn-in) of the k601 is very favorable, and better then the 595s. The k601s have a larger sound stage, more bass, and do not sounded canned like the 595s. They are very comfortable and light, more so then the senns, but the only thing i don't like is that the headband slowly slips down my head over a period of time, while the senns stayed put. Other then that i'm very pleased with the k601s

 

[QQQ]

I think 601 are slightly better overall headphones than 701.