It's funny that the HD800's keep getting the mention around here on Headfi..
I'm certain that some people would swear by them. However, I had the pleasure of auditioning them the other day with the Bellari HA540 amp, which had enough juice to power a small country
The source was my Iphone 4 with bass heavy Massive Full-On Psytrance, with tracks by DNA, Ananda Shake and Electric Universe (anyone who's anyone on that scene has to know who these are) ..
So here's my take: Comfort level... Sublime .. absolutely sublime.. I don't think I've ever worn anything more comfy and non-intrusive as these things.. and I've had the XB500's which are raved as one of the most comfortable headphones out there.. Construction.. Wow... that's all I can say, sheer brilliance there.. From the headband, the earpads, cushions, the visible drivers and sheer magnitude of these things.. it's really un-worldly to experience wearing and holding them.. In fact, they're so overwhelming.. when I held them.. I actually held them for a minute before I put them on.. trying just to figure out if I should listen to music through them or use them to go back in time..
So.. those are the pluses for construction..
As for sound... Well.. they're definitely Hi-Fi headphones.. on that there is no dispute... Wide WIDE WIIIIIIIIIIIIIDDDDDDDDDDEEEEEEE soundstage.. very airy, engulfing surrounding, surprisingly warm, laid back and soothing.. Very natural sounding headphones, no doubt..
Now, is the sound worth $1500.000 in my opinion, No. With construction in mind.. $900 - $1000 realistically speaking is fair..
The Drawbacks.. well, they leak.. not all that easy to drive, even amped.. and they LEAK... I wouldn't call the HD800's a fun headphone by any means.. they are too Hi-Fi to be fun.. Hell, I love my SRH440's, and I can tell you that they're not a fun pair of headphones..
I think for all round good-to-go headphones, those Panasonics sound like a steal..
Also, for those who are looking for a competitor for the HD650 and HD800's, I give you the Grado PS500 for on-ear design, which sounded better than the HD800 on all aspects (less the soundstage) and for what, $500 Retail.. And for Closed Back Circumaural design, I give you the almighty Shure SRH940. Truly, Truly underrated headphones and well underpriced - For $350 retail and $270ish online/street... if you have $1000 - $1500 to spend on headphones, give the Grado PS500 or the SRH940 a try.. most likely you'd get one, or the other.. or both before you buy the HD800.. and would still have money to burn on a portable amp and drinks..
But hey.. we're discussing budget cans... right... Yeah.. those Panasonics... look sexy..