I posted this in the Full-Size headphones forum, but after poking around here I realize I may have posted it in the wrong place. This may be a more appropriate place.
 
I have an extra set of Accidentally Extraordinary 51st Studios headphones. There's some physical damage to them, but nothing I can't fix. I like to tinker and learn how things work. I have some basic knowledge and can handle a soldering iron.
 
That said, I want to try out some DIY improvement to this spare set. I'm not sure where to start, however. Do I replace the drivers? (they're 40mm). Are there features that can be added that might improve the sound? I'm looking to have some fun and see what I can do.
 
Any suggestions?

Try some damping material like felt.
Or maybe swap pads. Or drill holes to make for a different bass response perhaps. Dunno..