My new house has a home theatre with 2 JM Lab Cobalt 800s Sub's. Both of them aren't 100% and one of them is definitely "broken" and since they were good/expensive I wanted to know where to start learning how to fix it if possible versus replacing it with a cheaper option. What happens with it is that if they sound goes above 1/8th of it's volume or so, it just makes a screeching sounds instead of the bass sound. The other speaker is mostly fine but if it goes above 70% of it's capacity or so, then the same thing happens. So with the second one, it realistically never happens in movies, while the first one I have had to disconnect because almost any amount of bass makes it happen.
Most searches I have made have resulted in how to fix a broken sub that just doesn't make any noise anymore. But they definitely still make a sound, and it's pretty loud and annoying. I think a decent way to explain the sound would be if someone put the front cover on the sub up against the actual cone and it's just hitting it and vibrating off it. Not sure if that's a great explanation though.
I know this is a basic question and you guys can't walk me through everything, but if you have any idea what it wrong, or the actual name for this phenomenon is (and not just "blown speaker" as I would know it). I would appreciate it, that way I can start my search somewhere.
Thanks
