Foam Dope

My recommendation: put new surrounds on your ten-year old speakers, enjoy for ten more years, repeat.

Thanks. There are a couple of products guys here have suggested. If you glanced at the product page could you tell me if these seem effective or a plausible fix to you.

http://www.simplyspeakers.com/speake...mi-1291fg.html

There are three reasons I can't get into re-foaming. The first is the probability I'll be around long enough and have the capacity to in another ten years is hilariously low. Heck, I wouldn't bet on next Easter, and the only reason I'd like to extend my stay so long is that the last time I was in a church was Easter 1966, so making an even 45 years of atheism seems like a good note on which to leave.

The second is if I DO make 10 years, I only have one working hand and it's doubly tough - at least - to do the re-foam thing.

The third is that I'm so spectacularly cheap, if I lasted ten years and got a pro to give me an estimate for a re-foam I'd probably drop dead right then. On the other hand, if the re-foam professional fixed them and kept them for his use, I could haunt him through the speakers. That'd be great!
 
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No

Would you be "the" JDub of Supramania fame?




.

I'm just "a" JDub of no fame at all. (I googled Supramania because I'd never heard of it. Seems to be auto related. I know about as much [little] about autos as I do about audio. But care rather less.)
 
I'm just "a" JDub of no fame at all. (I googled Supramania because I'd never heard of it. Seems to be auto related. I know about as much [little] about autos as I do about audio. But care rather less.)

Thanks for the reply. Your namesake on Supramania is also one of their resident chemical/petrochemical experts. I have not talked to him in a while and your literary styles are uncannily similar. Nice to make your acquaintance though. ;)



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I used this stuff from Simply Speakers...

http://www.simplyspeakers.com/speaker-repair-cone-edge-sealer-mi-1291fg.html

First on my 4 HPM-150 woofers, almost 20 years ago now, when Simply Speakers advertised in the back of Audio magazine. Still soft, flexible, no sign of deterioration, haven't rotted. Originals only lasted 14 years. These replacement surrounds with the sealer have been on now almost 20. What can I say.

Also have used it on my Baby Advents about 10 years ago on the new foams they needed, and I used it on the 15 year old original foams of my Optimus Pro 77 speakers I use on this computer. I've seen several posts about those surrounds, hard to find, having to glue two together to make it work. The originals are still in good shape here.

PVA? sounds suspiciously like Aileen's tacky or Elmer's white glue, probably thinned with water to the desired consistancy.....

I've got some 12" CTS woofers I refoamed 15 years ago with a parts express kit, foam is showing no real signs of deterioration, even with hot/cold damp/dry cycles and being exposed to all kinds of stuff in my garage system...wouldn't worry about it if suitable foams are available...

any sort of coating on the foam will stiffen it, raising the Fs and having a negative impact on low end response....where are you located? if it's near west michigan, I'll refoam them if you need to for the cost of foams and getting them to me....
 
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PVA? sounds suspiciously like Aileen's tacky or Elmer's white glue, probably thinned with water to the desired consistancy....
Yep something like that. Simply Speakers told me at the time it was a formulation that won't get stiff over time. What I do know is, it had extended the life of the surrounds of my Optimus Pro 77s. all of which I've seen on this site have rotted and crumbled to bits. Mine are still fine. So if some basically watered-down Elmer's does the trick, great I say! I don't particularly relish the thought of re-foaming 4 HPM-150 woofers, a pair of Baby Advents, and a pair of Pro 77s. Hopefully they will outlast me!
 
Lou

Thanks. There are a couple of products guys here have suggested. If you glanced at the product page could you tell me if these seem effective or a plausible fix to you.

http://www.simplyspeakers.com/speake...mi-1291fg.html



To be honest, I don't really know if this stuff will help or not. However:

The article you quoted claims that foam fails because it “dries out and cracks”. The Foam Guard from Simply Speakers claims to preserve the foam “by preventing moisture absorption”. Why am I skeptical?

If the FG does absorb UV, it may afford some protection, but the best way to minimize UV damage is to keep your speakers out of direct sunlight. However, nothing is going to make foam last forever. Maybe you might consider trading your speakers in for some that have rubber surrounds?

Here’s an idea: Put a large pickle jar by your favorite listening chair. Toss a quarter in the jar every time you sit down to enjoy some music. If you listen every day, it should only take a couple of years to collect enough to have your speakers professionally refoamed (going by the prices on the SS website).

Good luck!
 
I've mentioned before in another thread that I have a pair of old stock HPM-150 woofers that have never been out of their original boxes and factory plastic bags until about 6 months ago. Foams were completely crumbling and falling apart. So UV doesn't seem to have anything to do with causing it, likely would accelerate the process though.
 
I've mentioned before in another thread that I have a pair of old stock HPM-150 woofers that have never been out of their original boxes and factory plastic bags until about 6 months ago. Foams were completely crumbling and falling apart. So UV doesn't seem to have anything to do with causing it, likely would accelerate the process though.

Ed - I didn't mean to imply that foam would last forever in the absence of UV. If the lifespan of foam surrounds is 10 to 15 years, as I have seen quoted, then UV might be the difference between 10 years & 15 years. In your case, it is conceivable that additives migrating from the plastic bags to the foam could have contributed to their demise, but if the drivers were old enough they would degrade anyway.
 
Here’s an idea: Put a large pickle jar by your favorite listening chair. Toss a quarter in the jar every time you sit down to enjoy some music. If you listen every day, it should only take a couple of years to collect enough to have your speakers professionally refoamed (going by the prices on the SS website).

Good luck!

JDub is coming through with some great advice. I don't even have foam surrounded woofers and i am going to try it!

plus, unless you are Rembrandt, a professional refoam will be much better than any paint job you can give your surrounds.
 
Well I guess I am being doubly cautious, using sealer on my foam, and having a jar to put quarters in! :D

quarterjar.jpg


An Apple sauce jar though. And I seriously doubt the outgassing from the apple sauce rotted my old foams! Those woofers are about 31 years old.
 
The butyl surrounds on my purchased-when-new EPI M50s lasted 31 years, and got replaced. I'm 55 now, so another 25 or so years, and I'll be hiring one of AK's current young guns to have them redone a second time, I suppose. Whoever it is should be very experienced by then.
 
Can we all agree that foam rubber disintegrates over time?

If it didn't they'd call the stuff Kryptonite and even Superman couldn't destroy it.
 
In my book, something that cost $10 and lasts 15 years is acceptable. Even if you have to pay someone another $15 to replace it.

I'd rather maintain the designer's specs.
 
Here's the result so far on my 15 year old Pro 77s that are notorious for being completely rotted away by now...

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I speak from experience with the Simply Speakers product.:thmbsp::thmbsp:
 

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Foam has specific characteristics that were an essential part of the speaker design. Changing the mass or flexibility of the foam will change the driver resonance point and affect the low frequencies.

Modern foam is more durable that that used a couple decades ago. It's not that hard to replace.

Yeah, but deteriorated foam also affects the sound then if the surrounds become less supple and brittle over time. Wrote the following in a similar thread:

There is a wonderful stuff you can use to make your surrounds (far) more durable, if they are not too far gone, and it's called STP Son Of A Gun Protectant. Yep, the stuff you use in and around cars. It immediately lifts the dryness and brittleness of foam that's been there for years. The surrounds become more supple and provide more air tightness. Don't ever use silicone on foam, as one expert (by the name of Troels Gravesen) mentioned on his website *. That's alright for rubber surrounds, but it will eat away foam in a slow motion sort of way (remember how the bodily fluids ate away metal in the movie Alien?). Make sure to apply STP gently. Use a thin plastic bag you spray it on first, then apply by stroking it on. A brush may form a risk.

I bet that 'STP doping' brings the surrounds closer to their original specs than any replacement foam surround.

* http://www.troelsgravesen.dk/C17.htm
He's sooooo wrong! Told him that. It's the undiluted silicone that dissolves foam. How do I know this? Well, I still have a small bottle of liquid silicone, and tried it once.
 
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