Troubleshooting the mids:
Here's what I started with last week (Read further down about the mods I made today):
Here's my T50RP mod ; nothing here was my invention:
1. Separate ear pads from double back sticky tack.
2. Remove 4 outside screws that hold on the baffle.
3. Carefully separate baffle from cup making sure to not stress the delicate solder points.
4. Fill holes in back of baffles with art supply plasticine clay (Claytoons 483 g.) and punch holes with screwdriver.
5. Cut off just enough stock damping felt over bottom vent to expose 1 vent slot; I used an Xacto knife.
6. Cut pieces of Akasa Paxmate Plus to cover the bottom of the cups.
7. Put back together.
I cut away the dust cover on the front of the drivers. This made no difference in SQ; probably because it is very thin and very permeable. I ordered replacements from Full Compass.
I was not satisfied with the veiled mids so I added:
1. Paxmate Plus on walls of cups.
2. 1/16" art supply felt over ear side of baffles to cover the naked drivers.
3. Paxmate Plus on ear side of baffle surrounding the driver.
4. Salvaged ear side baffle dust cover I previously cut away place on inside of cups covering 3 of 4 cup vent slots.
5. Wool felt square over back of drivers, leaving vent open.
The bass and treble were attenuated with these changes and the mids remained veiled.
So, today I:
1. Removed paxmate from the interior cup walls.
2. Removed felt from ear side of driver and left them naked.
3. Removed Paxmate Plus from false cup vent on inside floor (top) of cups.
4. Placed reflex dot of Paxmate Plus over cup screw housing on inside of cups in line with center driver square.
5. Covered 3 of 4 cup vent slots with stock black felt that came with the cans.
6. Left Paxmate Plus around ear side perimeter of drivers.
7. Removed wool felt from back of drivers.
I believe 1, 2, 3, and/or 7 (above) reduced driver's freedom of movement, over-damped the cups, and contributed to muffled SQ across frequencies.
With these mods, the bass now has authority, texture, and extension; the treble is unveiled and well extended, and the mids cleared a bit but are still veiled - slightly muffled. I am hesitant to make any more non-reversible mods such as cutting away the white stock felt on the back of the drivers.
I am interested if anyone has encountered this problem and discovered a solution.
Edited by bluemonkeyflyer - 7/9/11 at 9:06am