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Chris Brown
03-31-2014, 07:36 AM
When I read people talking about the life of speaker foam, I regularly see figures as low as 10 years quoted. I last had my JBL L150 speakers refoamed in 2002, so we're about a dozen years on now, and I work those 128H woofers pretty hard.

I'm curious how long you've had your foam last, after you already replaced it once. Also, did you find the experience of refoaming them for the second time more difficult than the first time? Just wondering because at that point you'd be removing user-applied glue from the cone rather than factory glue, etc.

Do you always just use the speaker until the foam fails or have you ever replaced your foam simply due to a certain number of years having passed?

Fort Knox
03-31-2014, 04:00 PM
When I read people talking about the life of speaker foam, I regularly see figures as low as 10 years quoted. I last had my JBL L150 speakers refoamed in 2002, so we're about a dozen years on now, and I work those 128H woofers pretty hard.

I'm curious how long you've had your foam last, after you already replaced it once. Also, did you find the experience of refoaming them for the second time more difficult than the first time? Just wondering because at that point you'd be removing user-applied glue from the cone rather than factory glue, etc.

Do you always just use the speaker until the foam fails or have you ever replaced your foam simply due to a certain number of years having passed?

If they work..... I'd just keep on rockin':)

rdgrimes
03-31-2014, 08:08 PM
Depending on the quality of the foam used, they can get pretty loose before they start to come apart. They'll get very brittle to the point where you can easily poke a finger through the foam. Things like UV and smoke will speed things up a lot.

But yeah, if its working don't sweat it.

audiomagnate
04-06-2014, 10:47 AM
I think ozone or some other component in air pollution is a big factor. Foams around here (western Colorado) seem to last a very long time, up to 40 years, while foams from more polluted areas don't last anywhere near that long.

DavidF
04-06-2014, 10:53 AM
When I read people talking about the life of speaker foam, I regularly see figures as low as 10 years quoted. I last had my JBL L150 speakers refoamed in 2002, so we're about a dozen years on now, and I work those 128H woofers pretty hard.

I'm curious how long you've had your foam last, after you already replaced it once. Also, did you find the experience of refoaming them for the second time more difficult than the first time? Just wondering because at that point you'd be removing user-applied glue from the cone rather than factory glue, etc.

Do you always just use the speaker until the foam fails or have you ever replaced your foam simply due to a certain number of years having passed?

Greg Timbers mentioned in last year's gathering at TiDome's that regular use of the woofers will extend the life of the foam. No mention of why that is but since you have yours in constant use....?

BMWCCA
04-07-2014, 04:31 PM
Greg Timbers mentioned in last year's gathering at TiDome's that regular use of the woofers will extend the life of the foam. No mention of why that is but since you have yours in constant use....?

In a recent discussion about tire deterioration due to age, a friend who is an engineer and also testifies in trials involving tire-related-accidents mentioned that the regular use and heat-cycling of tires actually keeps the rubber from aging and cracking. He cited better flow of the waxes and oils in the rubber. :dont-know:

Fort Knox
04-08-2014, 04:09 AM
I think ozone or some other component in air pollution is a big factor. Foams around here (western Colorado) seem to last a very long time, up to 40 years, while foams from more polluted areas don't last anywhere near that long.


An extreme failure rate ..is sunlite on my 69 Chevy...seems I was replacing the
rear deck window speakers every 2 yrs. or so....back in the day

Chris Brown
04-08-2014, 08:11 AM
Things like UV and smoke will speed things up a lot.

I've done a good job keeping the sunlight away from my speakers over the years. As far as smoke goes... well they certainly have not been exposed to much tobacco smoke, that's for sure ;)


Greg Timbers mentioned in last year's gathering at TiDome's that regular use of the woofers will extend the life of the foam. No mention of why that is but since you have yours in constant use....?

Makes sense. My L150s spent at least 10 years sitting unused in my Uncle's house before he gave them to me. The foam was still intact but crumbled the first time I touched it.

I also wonder what the longevity of replacement foam is compared to original foam? I assume improvements have been made over the years that might contribute to longevity? Is it possible that we're getting to the point where foam lasting 30-40+ years will be common?

jbl
04-08-2014, 09:56 AM
When my 2235 are due for a refoam, I plan to use Factory glue instead of the white glue commonly used. My concern using factory is, how easy/difficult it will be when a second refoam is due. Will removing the old surrounds a few times compromise the cone? Anyone experience this?

audiomagnate
04-08-2014, 01:20 PM
When my 2235 are due for a refoam, I plan to use Factory glue instead of the white glue commonly used. My concern using factory is, how easy/difficult it will be when a second refoam is due. Will removing the old surrounds a few times compromise the cone? Anyone experience this?

I don't know what the factory glue is, but the white glue found in refoaming kits is just repacked Eileen's Tacky glue, and is water soluble. I don't know how old you are, but my freshly refoamed 136A's will probably outlive me, so I'm sure as heck not going to worry about it!

jbl
04-08-2014, 01:32 PM
I don't know what the factory glue is, but the white glue found in refoaming kits is just repacked Eileen's Tacky glue, and is water soluble. I don't know how old you are, but my freshly refoamed 136A's will probably outlive me, so I'm sure as heck not going to worry about it! I ask since JBL never sanctioned refoaming. When the surround went south, it was time for a recone. The original glue was black glue.

remusr
04-10-2014, 08:48 AM
Foam seems to last much longer for those in dry areas - Alberta, Colorado, etc - vs those in high humidty, esp coastal, locations. My 1984 L100T foams still seem as soft as new for example and I've had them 31+ years. I don't know how but could it be that high humidity deteriorates, or helps deteroriate, the foam somehow? Could be bacteria or something? Maybe in combination with UV and smoke/pollution, but I think UV levels would be very low in a house, esp with E-windows and window coatings used commonly now.

Fort Knox
04-10-2014, 03:57 PM
In 1971 I mail ordered ..2.... 411-8A...Altec 15's 5 cu ft infinate baffle design (w/cloth surround and
sticky latex surface..16lbs cabinet pressure (they claimed)
cne was damaged ...the replacement they sent back was foam...I was told the specs were ident.
I was not pleased ...later on..... the foam sp. blew out and released the cab. pressure design
I simply sold the pair as is

Chris Brown
05-31-2014, 04:28 PM
Damn I guess it's time :( I didn't expect my L100Ts to need it before my L150s.

http://gotnorice.com/l100trerefoam.jpg