deafdoorknob
1000+ Head-Fier
The TH900 pads fit. Just like Hifiman, you take the mounting rings out of TH500RP pads and slot them in the TH900 pads. Unless, like me, you take the TH900 pads off the TH900 and then they already have the mounting pads inside. I found the headphones to sound more open and I could hear the cymbal crashes and the crunchy guitars much better but some of the bass was sacrificed. I did not listen for too long because I wanted the pads back on my TH900's and I ultimately preferred the sound of other pads.
Cheers.
thanks for the insight! btw, have you attempted or tempted to swap the cups of the th500/900?
in essence, a ZMF - style closed fostex planar
... and a semi open dynamic driver fostex as well if the cups are swappable!
I am a little tempted to try that when I get my th600 back from my friend *evil mad scientist laugh*