Could you describe the concert hall you attend? What position do you choose for your body while listening? Don't you sit backwards to the stage? Whenever I hear rock drums or percussion, what I hear from the HD650 sounds completely false. No matter the drums were amplified during the live event or not. There is most of the snare drum crash sound lost on the HD650. The resulting sound is more of a fart while sitting on the armchair. The overall resolution, accuracy and speed of the HD650 is far below HD800's abilities. There is just no comparison. It's a budget family car against a sports car. You can read in the User's Manual what the HD650 were designed for. There is a funny passage about "new listening habits" saying nothing more than people don't want accurate and analytical sound after all. Reading between the notes - the HD600's, being overall more accurate became a PITA for many "hi-fi" equipment users giving unbearable sound which in fact wasn't their fault but caused by sound quality provided by equipment with the hi-fi sticker. So, Sennheiser had to prepare a product being pleasantly sounding from any device inluding onboard PC sound cards. The recipe for this is simple and visible on FR graphs with no 1/3 octave smoothing - bumped up bass and lower midrange together with deeply cut frequencies past 10kHz.