Electrical tape for the bass ports. I don't think you need dynamat and acoustic foam at the same time, same with plasticine and tungsten putty.
Quote:
Originally Posted by
Omark12 
About to buy my own T50 RPs and some modding materials. Placticine, tungsten putty, silverstone accoustic foam, dynamat, cotton balls, and shure 840 pads. Am I missing anything?
I got the T20RPs working by virtue of having a 3.5mm to 3.5mm male to male cable which I use for the auxiliary port in the car. It fit the T20RP's removable cable slot perfectly, so I was able to use it without an adapter.
My T20RP MKII modding pictures and explanation (Click to show)
Sorry for the bad picture quality again.

I mass loaded with plasticine. Standard procedure.

I filled the little headband screw area with plasticine as well. The T20RP MKII does not have the cover for this area, so I thought I'd cover it myself.

Then I covered the top of the plasticine with acoustic foam on the headband screw area. This is my replacement for the felt that is on the T50RP models.

I filled the rest of the areas with acoustic foam on the side opposite the driver, careful not to mess up the area where the screws go through.

I put two teased cotton balls into the baffle as well before sealing it back up.

Final step for my modding was to add a ring of acoustic foam to the outside to puff out the stock pads as well as isolate that area a bit more. More isolation to the pads can't hurt.
Not pictured: I covered 3.75 of the 4 bass ports with 2 layers of electric tape to tune the bass and treble.
My first impression after I did the first mods was slightly disappointed. I had mass loaded, acoustic foamed, one cotton ball, and 3 bass ports filled. The bass had come out to play, but the highs were massively recessed. I covered half of another bass port and added a cotton ball to each side and that let the highs come back to a level I liked. Sound balance feels very nice, significantly better than stock, but I still find it slightly behind where I want it in treble.
The Lows: Although not as hard hitting as the +10dB equalization that I had done before at stock, the bass was certainly significantly better than stock with significantly greater presence. Compared to the aggressive equalization, the bass slam felt greater before mods, but I feel like the bass has tightened up after mods to compensate. There's enough bass for me with 3.5-3.75 bass ports covered, I wish it were a bit more but I feel like I start compensating the upper frequencies when I mess with that.
Overall, I'd call the bass on the quick side. Zabava by EnichKin's bass line is rendered quickly and cleanly, as clean as any headphone I own can do.
The Mids: Very clean and detailed. The lower mid hump is gone from the sound signature. Vocals no longer feel unnatural or congested. The issue with the singer feeling too far away has been corrected. Overall, I'd say they beat my beloved KRK KNS 6400 in terms of mids detailing, and that's the KRK strong point. Killer mids, though. The detail that you could hear in the stock form has come out very nicely with the more balanced sound signature. I'm very impressed overall with the mids.
The Highs: After mods, they have sufficient volume in the upper highs (12khz+). It can hear the odd high pitched clicking in Holiday by Swimming with Dolphins (as far as I can tell, this sound is centered at 16khz, but extends in both directions, of course), but it isn't overwhelming. I'm admittedly a guy who likes very bright headphones (I love Grados, bump up the treble on my KRKs, Beyers don't bug me, and I rather aggressive equalize Sennheisers) and these are my most subdued headphones of the bunch -- I wouldn't describe them as dark, but they're certainly not bright by my standards. My ears do yearn for a bit more treble than what the Fostex is giving me, but it gives enough.
Percussive attack is greatly improved. It's not perfect, but it's very good. When you start adding more percussive attack through EQing these headphones, you make sacrifices because the treble and vocals start coming forward more and also run the risk of sibilance.
I'm convinced of orthos. I'm still a little in awe of how good this headphone is. I still want to try and tune out the little bits I don't like about it, but this level of progress is crazy,
Edited by SanjiWatsuki - 12/31/11 at 3:02am