You make the 1540 sound really bad there compared to the HD650. HD650 can sound slow and have no sub bass, the HD650 are really good for slow music etc, but anything fast or with deep bass they are not as good, they also have the "3 blob soundstage" which can be annoying. But yes overall the HD650 are very good, the 1540 are faster and have sub bass while not losing much in other areas, ideally you would want more than 1 pair of headphones, for example HD650 + 1540 or D2000/D5000 etc. I also found the 1540 a bit grainy when using Xonar STX as headphone amp, but using NAD D1050 they sound good.