I have an older pair of JBL L88s. They have been in perfect working condition for years. When I hooked them up today they are making a loud popping noise. (From the woofer) I tried it on a different amp and it does the same thing. When pressing the cone in lightly it sounds fine, no scraping. Other then the popping noise they are still pumping out nice bass. I took one of the woofers out of the enclosure and ran it free air. Of course it popped really hard even with it very lightly on but I found when I was holding it down against the carpet with a bit of pressure it actually sounded more or less normal. There is a vent in the center of the magnet that was being covered when I was doing this. So far to me it seems like theres a problem with inadequate pressure for the sub to operate in the box normally. Why would something have changed? They are in they're stock enclosures and have been for the last 20 years.

Any ideas or tests I can try?

I tried swapping the wires to see if it was phased wrong but it didn't change anything.

I need these speakers for Saturday for my party so it would be greatly appreciated if you could give me a hand!

Thanks,
Zac

I played around with the 'High Frequency Level' knob on the back of one of them just wondering if weather it had gotten turned or something. At one point in the switch it was basically just the woofer playing and it sounded ok and then there were other parts where I could almost get the tweeter running with the sub with no problems but there was always still a bit of cracking. I am now gonna have to say that it is not so much cracking and more just HORRIBLE distortion. Any ideas?

Zac

I suggest you post this thread in the speaker forum.

Ian

Yea sorry, I posted this here at first because It hought it was a problem with the woofer.

Thanks for the tip. It is reposted now in the speaker forum.

This thread can be deleted.

Zac