To add to this lovely little discussion again...
The headphone bug bit me hard about 6 months ago. Grado SR60's, Sennheiser HD650's, AKG 701's, and a few amps later, I think I've got it under control now...
My work rig now consists of Sennheiser HD650's powered by one of the new Little Dot MKII's, linked via a DLO Audio dock. When it comes to raw and emotional 2-channel musical enjoyment, I almost prefer it to my home system. Yeah, really. It's that good.
I love the glowing happy lushness of the LD's tubes so much it's my new avatar.
I really,
really love the sound of the setup.