I'd love it if you could post the process for how you did the over ear mod. These are by far my favorite sounding portables, but I repeatedly keep thinking about selling them due to the comfort.
It's not that hard. Just look at my photos.
1. Buy Pad with diameter of 90mm outer and 55mm inner. You can buy anything. Remember the outer can be 85 or 90mm. But the inner must be 55mm minimal. It can be up to 58-60mm. For me I used razer kraken pad.
Buy a thick double tape, cut it about 4-5mm and stick it like in the picture (3 from above, the red background). You can see the green double tape there. Just don't open the outer layer of the tape. leave it. The idea is to make the pad to attach more firmly.
2. Make a damping like I make in the picture. Buy some polyester felt as a base. Use the medium thick. Don't go too thick or too thin. Too thick it will become too warm dull sounding, too thin and it will become too detailed,harsh and fatigue. Make a round cut, make two. Buy some foam with tape on hardware store. Stick 3 bar of it to the the polyester felt, then cut it round.
3. It's necessary to use damping, because change from on ear to over ear will change the distance of your ear to the driver, it will become shorter and will bring awful sound if you don't use any damping. Those diy polyester-sponge damping gives more distance from your driver to your ear.
The sound? Very good. It actually improves a lot. You won't believe it until you try it. The tricky part is in the damping. You can alter the sound as you like. Just experiment with it a bit. I used a combo of the medium thickness polyester with a little of the thin one, because I don't like it too bright , and yet didn't like it too warm sounding either.