Is th900 the best close back or is there something out there better.
Yes, the Sony MDR-R10 (the bass heavy version, imho).
Depending on what you want, select yourself something from this list:
- Sony Z1R: less colored, less sub-bass emphasis, more mid-bass emphasis (too thick imho), better mids, better highs
- Fostex TH900: in modded form, my preferred closed can this side of the R10, beats Z1R in mids as well, but still very colored
- Denon D7000: softer, smoother and more musical than the TH900
- Denon D7200: in stock form, the most linear closed can, but smaller sound stage, and feels more limited in the bottom end. You don't miss any bass though, just bass emphasis.
Some comfort issues with the head band.
- Massdrop Fostex TX00EB (or other varieties): a tad more bass and more treble and larger sound stage than the D7200, otherwise similar.
The AKG K872 might play as well. I don't like the Audeze closed cans. I have not heard the MrSpeakers closed cans.
If you can't listen to all of these, and have money, get a Z1R.
If you don't have that money, get a TH900 or one of the others.
Watch the Aeon, perhaps your best bet.
IMHO and YMMV.