BmWr75 simple mods (a BMF variant)
I've been restoring and building speakers for a few years now. So, decided to mod a pair of Foxtex T50RPs using only good practices I've learned from working on speakers. None of the mods listed below are new, they are just simple ones that are easy to do and really make these cans sound better.
1. Used Plasticine (modeling clay) to create a better seal between the driver baffle and the ear cup (reduces potential air leaks and maybe resonance/vibrations). Just cut pieces of Plasticine that are approximately the size of the outer groove that runs around the circumference of the ear cup (see picture below courtesy of BlueMonkeyFlyer), placed the Plasticine pieces in the groove and smear it in with your finger.
2. Installed Paxmate (Silverstone) foam in the bottom of the ear cup only (not on the raised area in the center of the cup). If I didn't already have the Paxmate, would have tried this mod without it and maybe used more cotton (see below) to make up for the missing Paxmate. The next step may be sufficient to damp the housing and driver.
3. Installed Riteaid natural adsorbent cotton square (~2.75" x 2.25") in the ear cup. (This cotton comes in a sheet rolled up in a square box. You will find it near the gauze and bandages at a Riteaid store.) Used half the thickness that comes in the Riteaid box. So, one ~2.75" x 2.25" separated into two pieces is all you need to do both ear cups. Fluff up each square to a uniform thickness by pulling the compressed areas apart with your fingers. The cotton gets compressed on the edges you cut. Also, if you put so much cotton in the cup that it gets compressed when the driver baffle is reinstalled, this probably partially defeats the damping ability of the cotton.
4. Installed Shure 840 pads.
5. EDIT - sealing up the 4 bass port slots 75-80% definitely helps tighten up the bass and improve the extension into the lower octaves IMO. I used the loop part of some peel and stick velcro (because I had it lying around) to cover the bass ports. Easy to cut to the correct size and stick right over the bass port felt.
This is the second pair of T50RPs I've modded. On the first set I followed most of BMFs V6.3 mod. On this second pair, I avoided the messy and more difficult Dynamat/Felt installation on the ear side of the driver baffle......and did not Plasticine load the back of the driver baffle (just to see if this makes a difference, can't tell it does so far).
This second modded T50RP sounds great to me and the bass is much better than stock.
The nice thing about these mods is they are simple and don't require chiseling off felt covers or in any way getting a sharp instrument near the driver. So, risk of damaging the driver is essentially nonexistent. Just be careful to not stress the wires where they connect to the driver. Damage risk is minimized if you only open up one ear cup at a time to do the mod.
All of these mods are completely and easily reversible also if you don't like them.
Edited by BmWr75 - 2/5/12 at 6:21am