I agree with JoelPearce and others who advise against asking someone to make a mod for you. Instead, do it yourself. My first DIY headphones modification was 2 weeks ago. I read through this entire thread plus about a quarter of the massive Orthodynamic Roundup thread. I cherry picked posts/pix and pasted into a Word document. Each post is identified by the author. This made it easier for me to go back and check details of specific mods that most interested me.
The T50RP is really easy to open up, mod, and put back together. I've done it about 15-20 times on this one set and 6 times on T20v2. It does make a difference...with just about every modification. What sounds good to me, however, might not sound so good to you.
Follow the procedures outlined by smeggy, mrspeakers, joelpearce, sanchu, boilermakerfan, and several others within this thread. The supplies can be picked up for less than $10; I did mine for < $5.00 worth of plasticine and Akasa Paxmate Plus. Pick and choose what looks interesting/feasible and give it a shot. It's fun. Just be careful when separating the baffle from the cup so you don't pull the wires off from the driver and headphone jack solder points. You can use some hot glue on the 2 wires connected to the driver but avoid using hot glue on the jack connections. Hot glue on the jack connections prevents the jack from seating in its baffle receptacle when you're ready to close it back up...lesson learned.
Here's my T50RP mod with ideas from all of the above; nothing here was my invention:
1. Separate ear pads from double back stick 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 ordered Shure 840 pads but have not tried them, yet. I may add Akasa or felt to the cup walls. I may try felt over the back of the driver. I am hesitant to remove the stock white felt despite positive results reported by some on this forum.
The bass is textured. Mids are prominent. Highs are extended without fatigue. I'm happy with this but will probably continue to tinker because it is fun.
Off topic; same principles:
Here's a T20v2 I modded:
1. Roll a 6" rope of Elmer's adhesive putty tack and press against round driver on back of baffle. I used 1/2 of a 1 oz (28 g.) package per side.
2. Cut Akasa to cover bottom of cups; leave vents uncovered.
3. Cut stick-on felt and place around walls of the cups.
4. Replace stock foam puck to cover vents.
5. Cut Akasa for outside of baffle under ear pads; obviously leaving the driver uncovered.
6. Put back together.
7. Replace broken hanger with replacement that Smeggy gave me (Thx Smeggy!).
8. Sounds amazing; almost as good as modded T50RP; so I bought another set on ebay.
Price paid: $25 for phones and ~$5 for modding materials. I may try Akasa on the cup walls; Akasa on one cup vent and remove the stock foam puck; same as previous with felt on back of drivers.