I agree with Alex, the Focal's are a natural upgrade from the 650's. Just as musical, but with great bass, and open high end. I own both the Elear and the Massdrop Elex. Both are great, but the Elex are definitely better. Just make sure you get a good amp to match. I recently swapped out my Modwright Tryst for my Trafomatic Head 2. The cool part about the Head 2 is that it has 5 different impedance settings. When I initially hooked up the Elex I put the amp to the 50 ohm setting which seemed like the perfect match based on specs. The headphones sounded good, but not fantastic. In particular the bass and high end extension seemed off. I turned the knob to the 100 ohm setting and suddenly it was a whole new ballgame with everything snapping into focus. I've been into high end headphones for about 15 years and I forget sometimes how importance impedance matching is. The Tryst is a fantastic amp, but since you can't change the impedance it only works best with certain headphones. I've tried to sell the Head 2 off and on for years because I thought it was good, but not great. Well, with Focal Elex's it is truly great. So good, that I might actually consider selling the Tryst, which is something I never thought I would do.
Bottom line- find a headphone that is comfortable and meets your musical styles and then find the amp that really drives it well. You will be rewarded with fantastic sound for a long time.
