Thankyou for the help wje, as a last quick question, is there a mod (to the headphones themselves, not the pads) that you recommend? There's tonnes of them from putting clay in the backs and covering the driver with felt or something? It's a little daunting, is there one that is gaurenteed to give good results whilst not being very hard?
While yes, some users have placed other materials on the ear side of the baffle, it has typically been done for a few reasons.
1) It was explained the the orrthodynamic drivers are bi-polar (I believe) and need damping on both sides of the baffle.
2) Others have placed materials on the ear side of the baffle to bump out or raise the ear pads to provide a better seal or slightly raise the pads on one side or another to fit their own person head shape better.
Normally, when it comes to applying the modifications, I'd suggest sticking with the 4 or so basic mods that are performed inside the headphones first - as those items are proven and tend to provide the best increase in performance from the headphones themselves. The other enhancements should probably be done one at a time so you can determine the value of the modification. Granted, these mods cost very little to purchase the materials, so really it's just your time that is spent. However, doing this smaller simple mods as "extras" will possibly provide big improvements for some users and lesser improvement levels for others. It all depends on many variables.