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Static in Woofers after Refoaming

M

Mike232

New Member
I'm sure I could dig through the thousands of posts here about this problem, and I actually started to, but there are just so many that it seemed simpler to post my own question.

I'm not new to refoaming. I did some JBL Decade 16s a few months ago and they sound great! But I just did a beautiful, careful refoam on some 10" woofers for another speaker brand. I used a 30Hz tone to center the cones and it worked very well. Sad to say, after firing up the speakers, both woofers have a static/rattle. One just a little, the other really bad. The cones are centered. If I move the cones in and out by hand, there is no scraping.

So I guess there was more damage in the speakers than just the foam surrounds.
1. Is this problem possibly from playing the speakers with the foam surrounds rotted out? (I got the speakers at a garage sale, so don't know how they were used/abused).
2. Why didn't the static/rattle show up when I was centering the cones during the refoam?
3. Is there something I could have done to check for the problem before doing the refoam?
4. Is this problem potentially repairable? Should I take off the caps to look for something?

The spider suspensions look great; no sag.

Please, help!
 
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Is it possible that you could have dropped some debris into the voice coil gaps? It takes next to nothing to make a noise and can be outrageously loud. As Pete pointed out, sometimes the tinsel leads can rattle against the cone. And if the caps are not fully attached, they can rattle. And, none of these problems would show up if you move the cones by hand.

GeeDeeEmm
 
i had it with one of my p.a speakers after leaving them with dj.s at an all night party .. i thought the speaker was surely blown then found the loose cap .
 
Good thought re: the tinsels. That isn't the problem, but is something I'll keep an eye on in the future.
The caps are tight; I never messed w/ them.
I think it's a problem with a heavy rubber ring that goes over the foam edge and which centers a milled aluminum screw-down frame that holds the speaker in the box. I THINK (lightly) tightening down the aluminum frame may have distorted the rubber ring slightly, which may have pulled on the new foam. Am re-doing it (re-gluing the foam, this time with 1.5V battery) but don't see how to prevent the same problem from happening again.
 
Another interesting effect happens with my Spendor`s when checking them with a frequenzy generator around 50 Hz - bad and loud ventilation noises from the canvas dust caps mid/bass.
Coated them with woodglue so they are sealed. Noise was gone.440949197_o.jpg
 
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