View Full Version : Refoaming Speaker Kit Advice

10-12-2007, 03:00 PM
I got a speaker refoam kit and it came with the new foam, glue and gasket set. It did not come with shims and the instructions do not say to cut the cone open and install the shims. I have seen instructions on other pages showing the inner cone opened and shims installed before the foam is glued to the metal speaker housing. Has anyone installed the foam without the shim process? The speakers are Infinity SM 112.

10-12-2007, 03:03 PM
This should help:

10-12-2007, 03:04 PM
I have done it both ways. If you do not use the shims just make sure the speaker coil does not bind while you are doing the re-foam.

10-12-2007, 03:20 PM
Depending on the dustcap most cloth or paper dust caps can be removed carefully with a pen knife by lifting underneath and reused for an original look. Dented paper or cloth dust caps can be soaked in water for a short time and smoothed out, let dry and they look almost new.

Personally I prefer shimming, I've done woofers both ways and had better luck by shimming, YMMV

10-12-2007, 03:36 PM
If you shim, it will be mechanically perfect.

I've done it both ways, and have only "missed" on one woofer out of 6 that I've done without shims.

I was able to correct that one by rotating the woofer until it "sagged" away from the rub. :smoke: Lucky.


10-12-2007, 04:39 PM
Just hope it's not a JBL as they have very tight tolerance voice coils and shimmiing is almost a must!

10-12-2007, 04:46 PM
Yesh, indulge us- what is the speaker you're shimming?

Older Boston Acoustics and EPIs and Genesis are all reportedly easy to do.

Some JBLS, Infinitys and the like, not so easy.

10-12-2007, 05:06 PM
There is a woofer surround seller named Rick Cobb that was recommended to me by several AK members that uses a process to align the woofer without shims or cutting the dust cap. His kit includes a CD that creates a 30 cycle tone through the woofer that you play during the final step where you glue the outer surround to the speaker rim.

He sells on Ebay, if you search "best speaker foam", you will find him (Ebay name: looneytune2001)

I used his product with good success to refoam some JBL L26 speakers.

Cheers, Snade

11-08-2007, 08:14 AM
Yesh, indulge us- what is the speaker you're shimming?

Older Boston Acoustics and EPIs and Genesis are all reportedly easy to do.

Some JBLS, Infinitys and the like, not so easy.

I need to refoam a pair of Boston Accoustics A100 speakers. I have never done this before, so a couple questions:

**Who offers the best kits? Is there a noteworthy difference in materials from kit to kit?

**Should I attempt this at home? I have never refoamed a speaker before.

11-08-2007, 08:23 AM
These guys offer good kits with shims and instructions.
I have done hundreds of re-foams over the years, and I shimmed every one. I have had to do "0" over.

11-08-2007, 08:48 AM
When i did my first refoam i used the kits from . They give yor everything needed plus a instruction cd showing how it done. englissa

11-08-2007, 09:03 AM
**Should I attempt this at home? I have never refoamed a speaker before.

Yes go for it! It's not overly difficult and is very rewarding :thmbsp:

11-08-2007, 09:16 AM
I've personally bought surrounds from ReEdger and GordonW with great results. Last nite, I did the surrounds on my New Large Advents with no shims and no rubbing. YMMV, of course.

11-08-2007, 09:32 AM
I have used the alternate method with success. I use a AA battery to raise and lower the cone for gluing and set the initial centering of the voice coil. I then connect the speaker to an amp or receiver through which I am sending a LOW level 30hz tone for woofers an 100hz for midranges. I use my computer to generate the tones using a program called TrueRTA. It is downloadable on the web. I've done 5 pair this way so far with success on all.

11-08-2007, 08:16 PM
**Should I attempt this at home? I have never refoamed a speaker before.

Yes, by all means. I recently did my first pair, and was surprised at how easy
it was. I used the shims, and it worked out great!

11-08-2007, 08:42 PM
never shimmed a woofer ,never had a failure. glue the cone to the surround first and let completely dry. when you glue the surround to the frame exercise the speaker by hand while the glue is setting being sure of course that the voice coil is not rubbing and let the surround position itself on the doesn't matter if it is not exactly centered in the frame , what matters is that the voice coil isn't rubbing.

11-08-2007, 09:46 PM
I've done two Infinity's w/o shimming. Seems they have a very stiff spider (the cloth dust cover behind the cone) and it holds the cone centered pretty well. I agree that you do the cone side first and let dry completely (over night). Then do the metal frame (basket) and you can push the cone in and out while the glue sets. First push gently about 1/2 way out to the edge on one side and then in 1/4s (compass points) all the way around. You'll know in about a minute if it's tending to one side. Adjust the surround slightly away from that side and do the 4 point push test again. If all quiet, put bull dog clip or cloths pin on the important point and continue working your glue down the rest of the way around. As long as you work the glue down, keep testing for rub. If all quiet all the time, your there :)

11-08-2007, 10:29 PM
I bought surrounds from ReEdger. Did not shim. After I removed the old foam I gently pushed the cone up and down (and just a tad side-to-side). The spider was fairly stiff -- the woofer pretty-much sat-up nice and pretty all by itself so I figured no need to shim. Speaker: New Large Advent (Jensen Advent -- circa 1982/83).


11-08-2007, 10:56 PM
Wow...that's the exact same pair I did last night. Small world. Still haven't gotten around to listening to them yet. II just have to get a big a$$ pair of Altecs out of the way to get them in the spot! But, I'm going to replace the terminals on them first as I hate those stock ones. I also should have the new caps and resistors in for them from PE the first of next week.

Oh, I didn't shim mine either. I first glued the surround to the underside of the cone and let it sit for half an hour. Then, came back and did the surround to frame and used a hair dryer to help to set them up. 24 hours later, they look great.