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groover
06-06-2009, 06:36 PM
I'm in the final stages of re-foaming four 128H's from my 4411's. Everything has gone without a hitch thanks to Rick Cobb's kit and all the advice from this forum. One question though...

In trying to replace and glue down the 4 gaskets around the perimeter, they seem too snug to fit if I butt them inside the outer basket. When I let them sit comfortably against the new foam surrounds, they overlap the metal basket by just a hair, but enough to raise the end and make it not level.

Is it better to let them overhang the basket a bit or is it proper to butt them against the lip and let them press the foam inward a bit?

Photos coming soon.

Allanvh5150
06-06-2009, 10:37 PM
If they are from Rick and they are the correct ones, the 128H had two different size cones, get rid of the old surround material, glue the surround to the cone and let it sit until dry and then the new foam should sit inside the frame perfectly.

Allan.

groover
06-07-2009, 07:17 AM
I might not have been clear, Allen. The foams are a perfect fit. They glued down perfectly inside the basket with amazing tolerance. The pieces that don't exactly fit are the four gasket pieces that glue over the top of the outer foam edge. These are the gasket pieces that have little slits where the four screws go in. These pieces don't quite fit within the lip of the basket and the raised edge of the new foam surrounds.

midlife
06-07-2009, 07:38 AM
I have never refoamed a speaker, however I would venture to say you do not want the gasket pieces to interfere with the surrounds' suspension roll.

rek50
06-07-2009, 02:22 PM
How about sanding them "just a hair"...

Allanvh5150
06-07-2009, 06:39 PM
Gotcha. All the 128's that I have ever done, I have always reused the original foam gasket. The originals are 11mm or 7/16" wide. If they only just touch the foam roll I wouldnt be too concerned. The ones that I have here have a gap of 1-2mm. Are yours the same width?

Allan.

tjrad
06-17-2009, 12:16 PM
Hi,

I have the same problem with the gaskets. They seem like they are a hair to wide and press up against the foam. The question I have is, are they really necessary? If you are mounting them back in JBL cabinets like L112's, they are never used... Can I leave them off?

Thanks,
Tom

SMKSoundPro
06-17-2009, 12:48 PM
No. Do not leave them off.

I always take the foam surround gaskets and gently stretch them in my hands, then put them into place. Align the mounting hole and gently massage them all four of them into place. Lay the driver on its face on a flat surface to set and dry. Then all is well! Sweep on a tone/signal generator to make sure all is centered and sounding clear. Then back into a cardboard box, cone up, for storage, or back into a cabinet.

Scott.

tjrad
06-19-2009, 08:30 AM
Thanks for the advice....

The problem is that I bought the speakers re-foamed but without the gaskets. I can't find the foam gaskets so opted to get the cardboard ones. Based on what you said, I guess I should sand down the cardboard ones and glue them on. Does anybody know where to get the foam gaskets?

evans224
06-20-2009, 09:57 AM
[email protected] ([email protected])
Email Rick Cobb-he sells surrounds to most of us here. He should have the correct gaskets.

tjrad
06-23-2009, 10:19 AM
Thanks.. I checked with him and he didn't have any..

mech986
06-23-2009, 01:34 PM
4411 exploded diagram here:

http://www.jblproservice.com/pdf/Studio%20Monitor%20Series/4411LR.pdf

The 128H woofer has 4 gaskets which is part #52806, listed in the Feb. 2009 parts list at $0.76. I just checked with Dave at JBL Pro Parts, they are on back order but expect to get some possibly by July 1, maybe more like July 15.

I'd suggest giving them a call around that time to see if they have come in or order them and be put on the wait list. For essentially $7 for both woofers + shipping, doesn't make any sense to do anything but use the OEM part. Hopefully, it will fit with the surrounds you have. If not, you could cut these down a smidge.

Hope this helps.

Regards,

Bart

tjrad
06-25-2009, 08:27 AM
OK. Thank you for investigating. I will wait and check back with Dave in July.

Tom