Headphones

[Mach]

I use a pair of semi-open AKG 240 & K66  Phones to reference back and forth which both have a flat response for mixing purposes along with my studio monitors.
For tracking to avoid bleed it's the Audio - Technica ATH M50'S and they sound terrific.

[T.C. Elliott]

I ended up eventually buying a set of Sony MDR-7506 headphones and i love them to listen to music and to mix on.

re: mixing on headphones:  I just recently wrote and recorded 12 songs in 36 hours and then mixed them the following two weeks and at least two songs were almost completely mixed on those headphones. I did my final exports and tweaks on monitors. I cannot figure out which two they are. Granted I did a ton of writing, recording and mixing in a very short time. But listening back I couldn't tell you which ones were mainly headphone mixes and which ones are completely monitors. I would say that if you learn your headphones (what the bass response is, what they accentuate or not) just as you should with your monitors, then it really is a viable option. Just be aware going in that there are limitations.