Modding Fostex T50RP headphones

Not much here on the Fostex mods, possibly this thread could die like prince Andrews' reputation...

On the off chance someone else has modded or bought some modded Fostex phones, I'd just like to ask for opinions and experiences. I picked up a mint pair of ex demo T50RP mk3's for a bargain so thought to give it a go. Instead of paying silly money for a few bits of felt using the Mayflower kit, I got everything from Amazon. Now I have enough to do around 50 headphones for the same money!

Reviews of modded phones are generally very good especially the Argon mk3 from ModHouse Audio. These cans can really shine if done right it seems. If someone here has some Argon's, I would love a little peek inside ;)

The basic method involves lots of damping - acoustic foam on the insides of cups and modelling clay on the driver baffles. Then according to taste, felt over drivers and cotton/ natural felting wool inside cups. I had the sense to weigh each baffle after adding the clay to get them both exact. Upgraded pads are a must with these, so have a couple types to try.

The 3D printing files for the open Alpha cups, kindly donated by Mr speakers, are available on on HeadFi. So will hopefully try these out sometime.

If someone is thinking of trying this then get in touch, I'll send everything you need.


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Thanks Chalky yes saw that on RobRobinette site. Thought of trying it but for now I simply replaced the existing socket with a non locking one. I butchered the sound with the first mods with way too much clay in the baffle. Subsequently improved it but not brilliant so a way to go yet tuning them.

Not sure if you have seen the Open Alpha project where you print your own ABS cups thereby recreating the Alpha Dogs by Mr speakers. Supposedly very good.