I thought this was hilarious and relevant to the HD598 thread.. probably the best description for HD598's sex appeal:
kwadgauy: Don't comment if you don't understand. These have burl wood accents. Burl wood is the closest material in nature to the composition of cochlea of the inner ear. This produces resonances that standard headphones cannot possibly replicate. If you combine those with green marker on the rims of your CDs and oxygen free cables, you will hear music that is, quite literally, more lifelike than the original recording. Or if you prefer mp3s, 128kbps will sound like 320kbps with these headphones. The resonances produced by the burl wood literally increase the effective bit rate. There is a warning on the headphone package that the super-lifelike reproduction of these headphones can cause epileptic seizures in some people.
Pollution has killed off all but a small number of the burl trees from which burl wood is obtained. As a result, it is extremely rare and expensive, and that is why you almost never see it used for headphones.
Someone at work saw me wearing my HD598s and asked me if they were an old pair of my Dad's headphones from the '70s. He wasn't kidding...