elfgesang: That's a shame, but i totally get it. If a headphone is not comfortable to me, i let it go no matter how good it sounds. It's just too distracting. For me the 800S is super comfortable, since my ears are on the larger side. On the 660S my ears would touch the inner foam which was a bit annoying but other than that i loved the secure fit.
I have owned the massdrop
HD 6XX (HD650 version, sounds the same but cheaper), and I too did not like that my ears touched the foam. The sound was inferior, lesser soundstage, less clarity, muddy bass.
But it was way cheaper so okay. I did like the design of it, it looked like a proper headphone. I have sold them, after I had the HD800S. I could sell them for about 15 euro loss, after having it for almost a year, so I have positive memories about them. One guy is happy with it somewhere. After the HD800S for me it was only collecting dust.
These I did not own but tried:
I have tried the
Focal Clears, I preferred the HD800S sound, mainly because of the soundstage. The Focal Clears looked much better, but I think the sound and comfort is slightly inferior. Maybe the bass was a bit superior, but less detail in the music and smaller soundstage. The Clear puts the music in your head, the HD800S surrounds you with music. The Clears have the advantage tough, that they sound great from a cheaper source, not that picky. They are enjoyable for younger people I think. I also dislike the pads wear out after some time, don't look that pretty anymore, and are super expensive. For the HD800S, pads last longer and much-much cheaper to replace.
The
Hifiman Arya still didn't beat the HD800S, maybe an equal at most. Some may prefer the Arya, I can understand that, depending on source and taste. The Arya is superior in bass response, a little bit less clarity and detail I think. A bit narrower soundstage. Comfort is equal.
The
ADX5000, well, had more clarity, but since then I have improved my chain with a Violectric clone amp and silver cables, so if I compared them now, maybe the difference is less. It touches your ears, which I dislike after the HD800S, maybe you can remove that fabric which protects the drivers from dust, so your ears fit. It is possible I would change to that, I think the ADX5000 surpasses the HD800S in clarity, detail. The soundstage may be less, but gives you an airy, effortless sound. A more vivid, alive sound. The HD800S is a bit dull next to it, well a bit more relaxing maybe. The looks and build quality is also better, built like a spaceship. It's a possible upgrade from the HD800S.
The
Hifiman HE1000SE was superior in sound, in comfort an rough equal, I think it also looks better than the HD800S. It is more expensive. The sound may be "too much" on the long run tough, too much detail, too bright. Maybe on the longer run I would prefer the HD800S from a quality source, it is not an animal, but a tame beast.
The HD800S are my endgame, unless I win the lottery and can afford something like the
Susvaras with quality source or the
Sennheiser Orpheus \ HE-1.
Maybe the
Hifiman HE1000V2 stealth can come into play later, I don't know, I don't think it's worth it or better for my taste. Maybe try it one day. Maybe pick up a used
ADX5000 it has a normal price and somewhat better sound I think, but I need a new listen. Definitely properly built, doesn't look like a cheap toy.
I have also read on local forums, that wealthy people upgrade to fancy headphones like the HE1000 or Utopia or Stax, but still buy the HD800S again, come back to it for some reason, maybe keep both. I think the HD800S from a good source can have the natural, clear, realistic sound, not the overexaggerated, super-duper "too much" sound, that's why they buy it again. From a good source it's truly a great headphone.