Before you go into complex mods just test earfanatic's principle. try loosely placing a piece of foam, or even a rolled up length of bubble wrap aove your head. It might be all that's needed. I'm using something like this on a pair of modded and heavy (much more than 840s) Fostex T50RPs, they're now more comfortable on the head than my HD580s.
4/17/10 at 7:55am