Got a pair of these today. I was looking forward to them and my UPS guy decided to not leave them. I'm actually not too worried about this, but I wanted them TODAY!
Due to working until 8am I wasn't able to get to the door. Turns out they had come back.
No chance to really listen to them on my main setup yet because I had to work and had a early deadline.
I used them with my Total Airhead (portable) amp from Sansa Clip+ using FLAC files. I made a tiny Double Helix interconnect cable from some scrap wire someone sent me.
Really, really impressed with them in comparison to my HD-600/580 (have both..yeah i'm weird).
No bloated bass or massive mid-bass hump. There's some bass in songs that I feel like wasn't as present on the HD-600..or almost absent (maybe not). I don't mean it's making it worse or anything. Still accurate. These are songs i've heard millions of times. Biggest difference seems to be the soundstaging. It seems that some instruments sound like they're placed almost to my right and left and almost behind my ears! Like do you ever hear something in a recording with a good headphone and you're almost wanting to look behind you. The soundstage wasn't huge due to it being the HD-650 and used with a portable amp/source. Never got this effect with the HD-600/580 ever. I do with my Q701.
Female vocals with this setup so far are definitely better than the HD-580/600. The mids are much fuller sounding. I thought that if the HD-600 had any "thicker" mids it'd be ruined, but I guess not. You know...those upper mids don't really seem "laid back" or recessed or whatever. I'll know if my amp is adding any coloration in this area, but if any, it's probably mild. The Airhead's impedance output is around 1.7-2ohm or something like that. My Micro is a bit better at .5 ohm. The Airhead is pretty powerful and can drive the 650 (and Q701) with ease. Not saying it's as good as a desktop amp, but zero complaints.
I had the HD-650 about 2 years ago but no good computer DAC. I was mostly using various very good full size CD players to my Asgard or Micro Amp. I actually bought the Micro for the 650 and K702 last time and it was my upgrade. I bet the ODAC will be amazing with the HD-650. I should have time off on Sunday to waste half a day listening to music!
So far these don't sound bloated in the bass or muffled at all (yet). Just early impressions. Maybe the pair I had was a lemon. Doubt it. I do know that very warm recordings were kind of muffled and had lots of bass bleed. I didn't realize this until I EQed down the bass. Maybe something else was going on with my setup. I do clearly remember returning the first pair that sounded good and exchanging it for another (first had a paint defect). The replacement sounded a bit worse and it felt like something was missing.
Hopefully my impression of them doesn't change with the Headroom Micro + ODAC. I also have the E9 around to test out. I also bought a DHC cable for my HD-580 awhile back, but I usually just use the stock cable.
BTW it's kind of cool now having the HD-580, 598, 600, 650. I'm actually not a Sennheiser fan. More of a DJ100 or Q701 fanboy
Edited by tdockweiler - 11/15/12 at 8:14pm