Re-foaming speakers?

[Shawn Pixley]

I have an excellent pair of speakers for our stereo. I bought them from a recording studio many moons ago. Unfortunately they are 30+ years old. They would cost many thousand of dollars to replace with equivelent sounding speakers. Money that I would prefer to spend differently (or not spend at all).

The foam between the speaker frame and the cone has disintegrated. I'm going to order new foam to repair them. Does anyone have advice or guidance for the task?

[Tom Stenzel]

I have an excellent pair of speakers for our stereo. I bought them from a recording studio many moons ago. Unfortunately they are 30+ years old. They would cost many thousand of dollars to replace with equivelent sounding speakers. Money that I would prefer to spend differently (or not spend at all).

The foam between the speaker frame and the cone has disintegrated. I'm going to order new foam to repair them. Does anyone have advice or guidance for the task?

Yikes, my 30 year old JBL woofers just did the same thing. I'm looking for a set of replacement woofers but having a problem sorting out the sub woofers from the woofers. Seems any large speaker is advertised a sub woofer nowadays whether it is or not. What I would get wouldn't be big $$$, I just don't listen to music loud anymore. The floor standing pecan cabinets are in great shape and cover up some issues in the room corners so some rehab is in the cards.

As far as refoaming the old ones I would think getting the voice coil lined up is the big issue. Me, I'm going to chicken out.

-Tom

[Phil Thien]

Yikes, my 30 year old JBL woofers just did the same thing. I'm looking for a set of replacement woofers but having a problem sorting out the sub woofers from the woofers. Seems any large speaker is advertised a sub woofer nowadays whether it is or not. What I would get wouldn't be big $$$, I just don't listen to music loud anymore. The floor standing pecan cabinets are in great shape and cover up some issues in the room corners so some rehab is in the cards.

As far as refoaming the old ones I would think getting the voice coil lined up is the big issue. Me, I'm going to chicken out.

-Tom

Just have someone else do it, then.

Swapping some cheap drivers for the OEM JBL drivers would be an enormous mistake.

[Phil Thien]

I have an excellent pair of speakers for our stereo. I bought them from a recording studio many moons ago. Unfortunately they are 30+ years old. They would cost many thousand of dollars to replace with equivelent sounding speakers. Money that I would prefer to spend differently (or not spend at all).

The foam between the speaker frame and the cone has disintegrated. I'm going to order new foam to repair them. Does anyone have advice or guidance for the task?

You don't want to learn how to refoam on high-end drivers. Honestly if you have some high-end JBL or Electro-Voice or whatever stuff, I'd pay the reasonable rates experienced techs charge to do this work.

If you have your mind set on it, I'd suggest trying on cheap, disposable drivers to perfect your methods, before doing the big-ticket stuff.

[Don Bunce]

http://www.decware.com/newsite/refoam.htm

[Matt Day]

I refoamed a nice-ish pair of JBL speakers (8" woofer IIRC) and it went well. I'm not an audiophile but I don't think its necessary to align it exactly totally perfect. I think I did a pretty good job.

[Mike Cutler]

Hmmm......
This has me thinking I should look at the Klipsch Cornwall's and Heresy 1's I've had stored in the basement for 2 decades.

[Jim Matthews]

It's not that difficult.

If you don't drink coffee, and it's the larger drivers - you can manage.
I've seen your woodworking product Sean, you're up to this.

http://www.parts-express.com/cat/speaker-surround-refoam-kits/328

[Matt Meiser]

I just redid the drivers in our center channel speaker with a kit from eBay seller simplyspeakers.com. Couldn't have been much easier. They offer service too if you don't want to DIY and it's pretty reasonable too but shipping will drive up the overall cost.

[Phil Thien]

I'm going to reiterate that I think this is a job for pros, unless someone wants to take a few practice runs on some cheap drivers.

I've seen lots of first-time attempts that look like carp. I've also seen kits sold with glue that is too viscous (and runs) and surrounds that are the wrong size.

If these were 80's Advent speakers or EPI or something I wouldn't care. Vintage JBL/EV/Altec stuff is extremely collectible (and valuable) and crappy refoaming jobs will drastically reduce the value of the gear.

Some of these woofers can sell for hundreds of dollars each, used.

[Pat Barry]

I have an excellent pair of speakers for our stereo. I bought them from a recording studio many moons ago. Unfortunately they are 30+ years old. They would cost many thousand of dollars to replace with equivelent sounding speakers. Money that I would prefer to spend differently (or not spend at all).

The foam between the speaker frame and the cone has disintegrated. I'm going to order new foam to repair them. Does anyone have advice or guidance for the task?
How will you be able to line everything up properly? Doubtless gluing in the foam is pretty easy, but getting everything lined up so the coil drives the speakers freely, now that seems like a big issue. Going thru the trouble and not getting this right is highly likely to go wrong. Plus, if the foam is bad who's to say the voicecoil itself or the cones aren't bad? Why not just buy replacement speakers and put them in the enclosures you have?

[Shawn Pixley]

My understanding is that the typical method for alignment is shimming the voice coil to the cone.

As to the voice coil, cones, magnets, and cone, I am confident that they are good (I can visually see the cone is good). The speakers were working well up to a couple days ago when LOML turned it up louder than usual while I was at work. The speakers in question are 15" drivers. Replacing them with equivelent quality would be expensive.

The speakers in question are 4.5 way monitors. Each horn is isolated from the others (except the 15" bass and 10" mid bass). The current equivelent is something like Bowers & Wilkins 801 or similar. I doubt I could get equivelent speaker replacements. By and large, the quality of speakers has gone down (though many of the other components have gotten better). What is good for a guitar speaker is bad for an auiophile speaker. With a guitar amp speaker, you may look for a particular break-up at volume. With a home audio speaker you don't want any coloration of the sound. What I look for is audio speakers not home theatre level.

As you can see I am not enthusiastic about speaker replacement. The speakers need to give great sound in a 14'x45'x15' high room.

[william watts]

Many years ago I did that same job on a pair of Warfdale woofers. You need to remove the dust cap and shim the voice coil to keep it centered on the magnet pole peace. Then you can glue the foam surround to the cone and the speaker frame. I used acetone for solvent to desolve the old glue. In those days I had to cut my on foam, but they did work without any noticeable difference in performance. Later, in my working life, I had occasion to have speakers "reconed" and found this guy who was reasonable and reliable.http://www.nealspeakerrepair.com/about.html this is the way to go.

[Shawn Pixley]

So, I am happy to report that the speakers were successfully re-foamed. There was a hiccup on the way, but in the end it all worked out.

We ordered the foam kit and when I arrived we pulled the 15" woofers. When we removed the foam from the first woofer, we used alcohol right away when cleaning the surfaces. That created a gooey mess n the frame / basket. On the second, I scraped thoroughly before cleaning with the alcohol. Much better. The first foam was for a flatbevel on the cone. Unfortunately our cone, while flat beveled, was slightly smaller than their foam kit. It would have a maximum bond of 1/16" all around rather than the 1/4" orginally. We got on the phone and the supplier swapped out the flat bevel kit for the non-beveled version. This gave us an approximately 3/16" overlap.

The youtube videos showed the installers working much more sloppy than we did. We used a cut down acid brush rather than the q-tip. So we didn't really have excess glue on the cone. Reinstalled them last night and now good to go. Thanks for all the feedback.