I just received my HD 650 today.
I mainly listen to trance music and today I learned that the HD 650 wipes the floor with high-end headphones, that I used before, like Stax SR-407 and Sony MDR-SA5000.
These headphones excel in mid and high frequencies, but lack in the low end. This 650 is different, not muddy Beats bass, but very clean, energetic and full bass sounds.
I am impressed.
I also listen to trance and I'm really impressed the way these headphones work out with this kind of music where vocals don't have an outstanding importance as in other genres...