I have a pair of woofers that came out of a pair of Oracle Helicon speakers that need to be repaired. They are over 20 years old. The woofer surrounds are rotted. The foam has become sort of a sticky black tar. I tried to find a comparable pair online but i am not having any luck. I decided to refurbish the existing woofers instead.
Nitrile gloves, alcohol, small sharp chisel and cut up pieces of microfiber towel. I used parchment paper to cover my work surface. I used the chisel to scrape as much off as i could. Then i put down a clean sheet of parchment paper to finish it off with alcohol soaked pieces of microfiber towel. Cleanup took about an hour per woofer. Now i have to find replacement surrounds 🙂