Hi, I hope somebody can help me decide between these two. I'm wondering if there are other differences between the Sennheiser hd600 and hd650 other than the elevated bass response of the hd650. Are the hd650's superior headphones in some way, or is it mostly just a matter of whether you want the increased bass? It looks like from the Headroom graph below that the hd600s also have a bump in the highs. Are the hd600s bright sounding? Also, what is the perceived sonic benefit of using the hd650 cable for the hd600s? I'm looking for headphones with great tone, texture and midrange, while the highs would preferably not be up front and can be slightly rolled off; and the bass should be there, but without intruding on the rest of the music. Which of the two would more closely fit that description? I listen to a wide variety of mostly mellow music these days and will be temporarily powering them with an E-MU 0404usb until I build an amp. Thanks in advance.