Am using some older RT5s as rears for HT, one is having a strange issue where the main driver has a little scratchy rattle. I took it out to see if there was some separation somewhere or something silly like that, but everywhere visible is attached. Surrounds look fine, etc. But you can feel the actual area that is causing the problem.
If you (and please forgive the layman abuse of terminology and phrasings) "thump on" the cone gently 75% of it comes back with a nice taut tone like gently thumping a drum, "boomp, boomp".. 25% is flat. "blat" ( told you you have to forgive LOL)
Also if you manually "massage" the cone/driver throw or travel, its smooth everywhere except that same dead area.. there it almost feels "rusty" along the travel,. so it like light sandpaper internally.. and that scraping sound is exactly the sound that comes out of it at low volumes.
So I dont know if there is a possibility of rust, or of something else causing this, or if it is something completely different.
Either way, if there is an easy fix, I'd love to hear it. Or if a replacement of the RT5 main driver is worthwhile to replace how much is it and how do I get it.
I'm obviously not married to these as they are the lowest end Polks I own.. But they work great for rears matching RT7s and LS50s etc.
(By the way, after massaging that little scratchy travel area, the problem greatly decreased but is still there from time to time.
Please,... enlighten me.