I've got mine back together still working out some fine tuning, but they are sounding really good.
Pict's to come.
Here's a brief overview....
-Recabled to dual entry with custom magnet wire and teflon
-Sprayed on viscuous damping material in cups.
-840 pads
-Stock felt removed from front baffle.
-Stock felt replaced over vent and 2 slots blocked.
-Small reflex dot on the back of each driver.
-(1) 2mm slice of "pop-up" sponge placed tight against back of driver (this worked better than expected!)
Initial impressions- I think I'm in the same corner with BMF that less is more. In putting these back together I took it one step at a time and with just the re-cable and cup damping they sounded very stock but without the plasticky honkiness, although the highs seemed slightly recessed. They were very relaxed but good in the Ortho like presentation. After that I played around with the venting and tuned to the bass I like and added the reflex dot to bring some top end shimmer back. At that point they were sounding better than stock as best as I can remember from last weekend before I took them apart.
So then I added the slice of "sponge". Initially I was going to try some poly batting underneath but found that the little posts in the cup pushed the sponge right up against the driver. So I skipped the batting. And WOW! The top end really smoothed out and got all nice and sparkly. What's more I believe the upper mid spike levelled out. Bass is nice and tight, not extremely deep but more present than any of my other phones. But what really amazes me is how the soundstage opened up. Listening while going to bed last night I distinctly felt like I was sitting on stage with certain tracks.
Now, for my disclaimer.... I will spend sometime comparing them to my other cans and try my best to assess my owner pride and diy'er placebo effect (as objectively as possible). When I get a chance I will post some pics and longer term impressions, might take a few days as my GF is coming to town for the weekend.
-Dogwan