Sennheiser HD 600 open back -- best sounding phones I've heard. Amazing clarity and definition, and a HUGE sound stage.
But thanks to Rob for also turning me on to the Meze 99 Classics. He made me realize I needed closed back phones. Warmer sound than the Sennheisers, and also lovely to look at.
And for running or working around the house/yard, I love my Jaybird X2 wireless Bluetooth buds. The best sounding buds I've heard - even better than the Jaybird X3 and Jaybird Run.