So I got the HeadAmp audition TH600's last night and spent about three hours listening to a variety of genres, sources and found them to be an amazing headphone. Comfort is extremely good, both regarding earpads, headband and weight/balance on my head.
I fed them from my Pioneer rack system from 1978, which has a Spec 1 preamp and Spec 2 amp through the SG-9500 equalizer, sources started with my turntable, then it went to the Sony CD player and finally iPod touch directly into the Aux input via RCA's.
These headphones are a basshead dream - they will literally take anything you throw at it, and that is plenty of power. I would bump the loudness switch at times just to see how they reacted and they simply hit harder and deeper. Astonishing to be honest. And not a one trick pony either - clean, clear highs and mids that are great for vocals and female voices.
Playlist included Eagles One of These Nights (drums and cymbal response), Steely Dan Aja (percussion on this song is about as good as it gets with drum solos that simply are the gold standard to me), Dave Koz Whisper in Your Ear (to test separation and low level clarity), Boz Scaggs Lowdown (again with the cymbals "S" response), Zachary Breaux Small Town in Texas (percussion again), Celine Dion Halfway to Heaven (for both her amazing vocals and Kenny G's sax response). That's the highlights but I literally went back and forth for three hours last night listening to different songs on these and my Denon D7000's literally one after the other back and forth.
I'm sold. These are amazing headphones - funny though, the box calls them reference headphones. Flat response headphones they are not - unless you are looking for basshead reference. That is not a criticism, it's a funny little paradox - I LOVE bassy headphones and these do it all extremely well.
Oh, and the final comment - my Denon MD7000 (full Mark Lawton mods and angle pads) are AS GOOD AS THESE. In every way. I could not tell them apart for the most part. Stock would have been no contest - the D7000 would have gotten curb stomped.
So I won't be getting TH600's but if I wanted another comparable pair to add to my D7000/D2000/D600 stable, these would be it.
I do love these - the looks are understated in all black with the silver hardware attachments setting off the flat black, and the earpads may be the largest diameter inside in history. Very, very comfortable.