Back! And I promised folks I'd post things, so here's the 1st thing on my mind right now: Koss Porta Pro dynamat mod: 1. Rip off foam/ear pads and you should see this: 2. Cover it with dynamat like this: Also how to "improve" on dynamat: get regular dynamat and replace the stock aluminum sheet thing with metal foil tape material. Found here: Aluminum: (brighter sounding, somewhat harsh in the upper mid, but will work better with darker headphones, this is virtually indistinguishable from stock dynamat, me thinks) https://www.amazon.com/AMACO-ArtEmboss-Metal-4-Inch-16-Feet/dp/B000XAHG9K/ Brass: ("bitey" sounding, but not bright. More relaxed than aluminum. My favorite as I find it best for dark-neutral headphones) https://www.amazon.com/AMACO-ArtEmboss-Metal-4-Inch-16-Feet/dp/B001684AKQ/ Copper: (somewhat darker and "heavier" sounding than the other two. Best for HD600/800) https://www.amazon.com/AMACO-ArtEmboss-Metal-4-Inch-16-Feet/dp/B001685T1U/ What do I mean by "replace"? Well, scrape the black goo thing off the stock dynamat piece and then spread them on to the metal foil tape and use it like that instead. Also, you may want to have just a thin layer of the goo instead of a super thick one like stock dynamat. This makes the piece much thinner, more compact, easier to slot in other places, and you can apply it on surfaces where applying stock dynamat as it is would not make sense. *Actual* or *real* improvements to sound? Well, who knows. But it's worth a try, isn't it?