A very superficial view. 
Fortunately, the HD800 is not Nicki Minaj.

I guess you don't get the analogy of how sub-bass frequency is referred to as the "bottom end" of the frequency range, while buttocks on a person is also referred to as the "bottom end." It has nothing to do with being superficial--it was an apt analogy while being a bit tongue-in-cheek. And to be clear, I'm a composer/sound designer with a professional audio production studio, so my assessment of audio gear is from the point-of-view of a serious audio professional.

Word of honor I have respect for your professional activity, but the fact that you are a composer / sound designer is not unconditional argument. I am well acquainted with many of your colleagues, and I know what qualifications / competence at all different. I am a professional painter, but if I tell you that Mona Liza is daub (I do not think so) you are unlikely to believe it. And thank God!
Although, if you say that Beethoven is your name - I will apologize!
By the way, my personal opinion - HD 800 are extraordinary headphones, Stradivarius-headphones.

Well... I fully agree with your review. Well stated.

I think he'll come crawling back to the cross eventually... his impressions mirrors my own the first time I tried the HD800. It is not a headphone you should be quick to judge. It is also very transparent, it can be bright, dark, smooth, harsh... depends on the gear.

Good review, thanks,

oooh come on yuo lot. If it sounds radically different to pretty much all the other high end phones - Stax 009, LCD2/3 etc etc then it is they are ALL wrong, or the HD800 are inaccurate. This argument has been going round the forums ever since these phones were made, and it seems to me that they do some things really well, but others very poorly. Lets face it, who wants a track car to drive to work?

There are enough great high end phones out there to not compromise this much IMHO.

I just wish Sennheiser would make a Planar or Electrostatic to take on the high end offerings. Then I would get excited!

I don't think listening to something twice gives you enough experience with something to review it.

@kalrykh - It depends on who's doing the listening. If it's someone who has extensive experience with audio gear, worked as an audio professional, know exactly what to listen for, uses audio test tones and a carefully selected playlist of musical material that he knows like the back of his hands and use them to assess specific capabilities of the gear, and was listening in a controlled environment without distraction and noise, was using high-end audio source and gears in the signal chain, had other flagship headphones there to do direct comparisons with, and had ample time to do the listening tests, then even just one listen session is enough. 

Thanks Lunatique for your review; this is helpful.

Thank you Lunatique! I actually signed up just to leave this comment. I have read a lot about the HD800 and have been listening to it for the last two days. As a non-audio-professional, I was amazed at first at the huge amount of detail. With that, it was a lot of fun to listen to tracks that I thought I knew by heart and suddenly finding new things in them.
BUT, I was very disappointed by their lack in the "bottom-end" as well as by their obvious harshness / brightness. I wasn't sure I could listen to them for long in the long run. So, I am happy that I found your review, because I was already starting to think I might have "strange ears", when everyone is hyping them so much while I wasn't able to "look over" their (to me) obvious flaws.
A little off-topic here: As I trust your input - is it safe to say that a HD600 would be the best choice in the lower price segment for "pleasure" listening?
It is not, that I didn't have pleasure seeing all those details with the HD800, but it was just lacking the "power", the musical "feel" that I expect from listening to rock music.

@Philipondio - Generally speaking, the entire HD5XX/6XX line of headphones are a little lacking in sub-bass (but otherwise are great headphones). The HD650 is a little better but it's still not quite there compared to newer headphones today that can reach to 30Hz or lower and maintain a fairly flat response. 
 
The "Wall of Fame" at InnerFidelity run by Tyll Hertsens is currently the most authoritative source for best headphones in every price range and format. There's no other source that's as knowledgeable, comprehensive, and with equally good taste as what Tyll is doing at InnerFidelity: http://www.innerfidelity.com/content/innerfidelitys-wall-fame
 
Tyll favors the HD600 more than the HD650, but I prefer the smoother sound and slightly more filled out sub-bass of the HD650. Neither are as satisfying as could be, and I think you'll have to maybe spend a little more for something that can reach lower and remain flatter in the frequency response.
 
I don't know if you have to have open headphones or you're okay with closed, and if so, take a look at the excellent closed headphones in the same price range as the HD6XX series--some probably are a bit better in terms of having fuller range and overall a bit more neutral (which is critical for the best audio reproduction. There is no better "sonic signature" than simply audio reproduction that's as neutral/transparent as possible. All colorations are inherently flawed and problematic because they skew the frequency response in subject manners that may or may not be ideal for different people's tastes or music genre, while neutral/transparent sound skews nothing and make everything sound simply as they should.

Great review! I'm not an audio professional like you, but I find my listening experience very similar to yours. 

The HD800's have pretty good sub-bass extension, according to every graph I've seen and my own hearing. I guess an argument could be made for elevated bass in headphones due to the lack of bone conduction.

Interesting you reference InnerFidelity while talking about how overrated these are where he says of the HD 800s:
 
"When I set up my lab, the only headphones I knew I had to buy were a pair of Sennheiser HD 800s--they are as close to perfect as a headphone gets."
 
http://www.innerfidelity.com/content/brilliant-sennheiser-hd-800-page-2

It did not take me more than 3 mins to dislike these headphones. There is a huge void in the low and mid end frequencies. My songs which would normally have a thump, was entirely lacking. The high end had too much treble. Voices lacked warmth became of the missing bass. They shrieked and hurt my ear. 
 
I don't get it. How can people think this is the best headphone is beyond me! They "may" have a wide sound stage but so what? They're missing a lot of things. I still love my Grado PS500 over these by far and even the rest of the Grado line! They are still the best headphones I have experienced without the requirement of amplifiers.

I would tend to agree, the HD800s are very precise headphones, built with an unbelievably great chassis, and are super comfortable to wear. But that's where my compliments stop. It doesn't really do what other headphones near or even below it's price point can do with similar, if not more detail.

I've never heard these headphones so i can't comment on that, but as i was reading your review i felt the urge to point out that neutral bass is surprisingly little for some people. And also that the vast majority of music, with real recorded instruments, does not go near 30hz. So unless people have a lot of experience conducting ensembles with people playing the bottom octave of an organ, piano or contrabassoon, it's very difficult to know what exactly a perfect response to that region sounds like. It's also an awkward spot for our ears, because sensitivity to a given pitch will decrease drastically below 60hz