I enjoy my HD800S for classical, ambient, space ambient, vocals, celtic / medieval music and my HD 650 for EDM/techno and jazz. But I wished for a headphone that had the amazing detail and imaging of the 800S but with the thump and warm low end of the HD650. I was exploring many headphone options and am considered the ZMF Auteur or Atticus but then I decided to give equalization through foobar a try. I am listening to flacs. The results were shocking! I turned up 55 hz, 77 hz and 110 hz so it was a pretty steep decline from left to right and the 800S gave me a thumping rumbling sound from the earth in my techno tracks! I had no idea the 800S could produce such impressive sub bass. Put my HD650 in with the same settings and I thought maybe I had been listening to a beats by Dre or something lol... jk of course. I had no idea equalization could sound so good. I have now made my bass ramp much more modest as it seemed to take detail away from mids and strangely the upper end even when it was so aggressive. But with my mild ramp it gives the 800S a beautiful touch of warmth and musicality while still preserving tons of detail. The HD650 now sounds like what I imagine a basshead can would sound like with my EQ ramp. Just thought I'd share my experience. Would love to hear yours.