Are those still the stock pads?... I'm aching for a pair of better pads for mine.

These are Brainwavz HM5 pads. Tried stock pads, Hifiman velours, Alpha pads, etc. The HM5s had the best synergy. You can use them on the stock frame, might just have to use some tape around the rim to get a perfect seal.

I also tried a paper towel: lowered treble but also killed too much top end air.

I have made the experience that acoustic filters in front of the driver are no miracle thing that can repair too much of a high-end bite. If you go for too dense a material, you will cut high-frequency spikes all right, but you will end up with a thick, muffled and congested mess. If the material is not dense enough, it won't have the desired effect. You have to strike the balance here, and no filter in front of the driver can correct a f**ed-up top end. At best you can fine-tune a high end that is just moderately off.

Microfiber cloth does wonders to reduce treble in that area as well. I just snagged a pair of these to mess around with. Any chance you could snap a photo of the inside, Marv? I'm sure once I have the headphones in front of me, I'll be able to see where you put the Dynamat. But if you wouldn't mind taking a photo or two, it would be much appreciated!

I was more interested in the position of his modding material. Good pics though!

I got myself an entire roll of dynamat lite type stuff at Home Depot. It was in the roofing material section. $25 for 20 pound roll.

Or you could go to Worse Buy (with a car audio section) and get 2 square feet for $30.

Interesting. I was kind of looking for a slightly smaller quantity than that, but I guess I can use the leftovers in my car system.
About how much is in a 20 pound roll?