When re-foaming, be weary of the replacement foams thickness compared to the OG foam. Ive made this mistake recently and refoamed some woofers with thicker replacements and though I have working drivers now they dont seem to have the same excursion length as they once did : ( I believe the common term for this is "Foam Compliance"
Just refitted my old JBL LX-33's with rubber surrounds tonight (the old foam had gone brittle and cracked) - even so they still sounded great until I ripped them with a bit too much bass! :(. Repaired them tonight and can't wait to hear them tomorrow. As I understand, the rubber may sag over time, and I can always flip them upside down, but since I'm nearly 50 yrs old, hope they last me until my demise - I love repairing things rather than replacing, especially old second hand HiFi equipment that is quality and affordable (I bought the JBL's for £15 over 15 years ago and love them to bits (literally!). Thanks Paul for your excellent channel, I somehow unsubscribed a few years back, and forgot about it, but so pleased to have found you again tonight. Getting into producing music over the last year. Re-Subscribed! Best wishes to you and all at PS Audio.
@@petersouthernboy6327 perhaps it would be negligible to be noticeable on a sub woofer. Maybe a full range speaker or a midrange unit would be more apparent. It's Not an extreme high end system so as long as their is a nice rush of air it would satisfy most ears or chests.😋😋
Nice to know that long life foam surrounds are available but geez I've tossed away so much due to foam rot. It wont be easy buying anything wearing a foam surround again. Guess I'm gun shy about it now. edit: Glad you addressed this. Thanks.
Even though there have been break-throughs in modern foam technology, why the heck do JL Audio subs still kill their foam surrounds after about 3 to 5 years?
I have 2 sets of IRS IIIa's made within a few months of each other back around 84 or 85. I had to replace the foam on one set 25 years ago but the other set is original. Weird.
@Fat Rat It is odd. I'm the second owner of both sets. The set that is original foam are from the coast where I am and pretty much lived in Rec rooms and the one's that were replaced was from the middle of the country but who know where they were stored being the guy that sold them was trying to raise money to get out of jail so they may have spent some time in a storage locker. 😎
Thanks for your explanation. I am experimenting with a DML (distributed mode loudspeaker) approach for a sound installation in which i incorporate cymatics (visualization of sound vibrations in patterns). It might not seem pro hi-fi cause it's not. But in a sound installation for kids and students, it helps to relate the visual and auditory senses. I have a problem finding "surrounds" to test around 24 inch OD disks made of acrylic (3 mm thick), driven by exciters from the german compagnie "Visaton". I wonder if you know of a solution to make such big "foam surrounds" ? Any "H-channel" rolls ? Cause 24 inches is not available, and my project would benefit from a real surround. I'd be happy to send you pictures and videos, if this adventure seems interesting to you. Thanks for your clip. Martin Leduc, Teacher, experimenting sound art, and sound installations.
Foam has serious acoustic benefits. Better dampening and characteristics vs rubber. One of the reasons Bose uses them, and it can cost much more to use them vs regular butyl rubber - especially when mixed with material or through manufacturing so they don’t rot. Awesome video Paul, I loved this one. You’re one of the good ones dude, haha
I learn so much from this channel. I have been of the opinion that foam is always bad for long term use in speakers because I remember the first foam era. It's good to see that the technology has improved and we can now use quality speakers with foam surrounds again.
I bought my AR-3a speakers back in 1970. The foam failed in about 1983. I got replacement woofers from AR at the time. I then moved to Florida in 1990 and by 1995 the foam had failed again and there is a loudspeaker repair business in south Florida and they replaced the foam surrounds. 25 years later so far the new foam has not failed. I hope it is the "better engineered" foam. I also have a pair of AR-3 speakers from the 1950s with treated cloth surrounds that have never needed service for the woofers. Manufacturers used this foam for about 20 years and it apparently was breaking down in about 12 years and failing. Other things that use foam from that era also turn into powder as well.
Paul mentioned (in a talk on a different channel from about 5 years ago) that he had once _almost_ sold a synth to Walter/Wendy Carlos. Is there a place where I can hear that story or would you be willing to tell it? I know this is WAY off topic but with 10 minutes before I have to get in the shower, then goto work, it seems like the path of least resistance to perhaps get a question/comment answered. Thanks - ADam
@@jmfloyd23 Bought mine new from circuit city about 30 years ago refoamed about 10 years ago, still like new. Got them for $700 on sale and $700 was a lot of money back then.
GREAT QUESTION! One of my fave speakers had them but they degraded boxes still awesome replaced and on they go but the foam surrounds felt more delicate with the sound like the movement was effortless.
I always from first reading about their availability ( AR / EPI speakers ) wondered how close to spec are the replacements ? my guess, not very close but is it a factor ? old KLH spks used rubber coated fabric, Dynaco pure rubber I think.
Brings me back to rocking cerwin vega- vega series. 500 watts rms with 96 db sensitivity. I had two 15's and my buddies all had the kicker solobarics with 86 db sensitivity, and my amp just purred along nice and cool, good old school soundsteam reference 1000...Those darn foam surrounds though had to be replaced a couple times!!
I have a pair of Beolab Penta III speakers from the late 80s that need their mids' foam surrounds replaced. I recently bought a set of them and opted for the foam instead of rubber, to retain the original construction and sound. I'm hoping that this foam is new technology/material and will last a long time... I love these speakers!
Mine disintegrated! 15 yrs of Arizona sun peeking in my living room dried them out. I kept my speakers limping along while I looked for replacements and one day the paper cones evaporated. Foam worked great, but doesn’t last.
@brady alex As Paul was saying, foam is pretty ideal as it's a lighter material, it holds it's shape better, and it's cheaper. But foam degrades over time especially in high humidity environments. Rubber can last forever. The minor drawback to rubber is it is slightly less flexible, it can slightly sag some over time which can affect the cone voice coil alignment and it's more expensive. The drawbacks of rubber is minor though and because it can literally last forever without maintenance it is the best compromise.
@@sean_heisler - rubber is fantastic, but it will raise the resonance frequency, lower the XMax, and lower the sensitivity of the driver. Just be aware of that fact when you’re going from foam to rubber.
@Fat Rat Oh, good move. That probably helped them survive in such great shape for so long! Silicon oil based products like that will keep them loose and prevent harding over time. Those were cutting edge speakers back then with the passive radiator woofers! 👍
Hey Paul, I've got a pair of infinity SM-122's from 1990 whose foams are still in original and seemingly perfect condition. On Rear Surround duty right now ;)
I have a couple of beautiful 30 years old Kappa RS5 that I installed at my father's living room so he could listen his tangos waiting for second re-edging from a long time. Also I have a couple of 1985 crappy 10" 3-way Degader (an extinted argentinian brand of cheap audio) at my garage for dayly use. Exposed to a hostile enviroment of dust and metal working and with their foams still intact, so weird! :-)))
People are forced to replace rotted foam surrounds in their vintage speakers, but the kits and methods vary wildly. If you don’t use foam with very similar characteristics and install them near perfectly, the results won’t be great. Compliance will change, affecting low and even mid frequencies. Best let a pro do the deed.
Yes, you want to make sure you use the proper surrounds for the speakers. But to do it yourself is not hard if only the surrounds are to be replaced and you understand to be very careful with every step. Several TH-cam videos can teach you how to do it and ideally you find the tutorial matching your exact speaker driver or a similar one, if possible.
I've repaired foam surrounds that aren't too far gone by using a two part silicon of a very low durometer, such as the brand name Ecoflex 00-30 I use. I just paint it on using a very high grade artist brush. It stabilizes the foam and stops any further degradation. To ensure good penetration of the foam, both sides should be treated. But even the outside may be enough if the foam does not have any cracks in it. If it has missing pieces then it is too far gone and a surround suspension kit must be used first. Even the replacement surround unless one of the newer high grade foams Paul mentioned should be treated to expand their life by decades.
I bought 2 jl audio 8w3 on sale in the late 90s and opened the boxes a couple years ago. There’s hardly anything left of the surrounds and they’re unused.
How about doing a comparison video on the newer foam surrounds versus butyl rubber surrounds. I prefer the butyl rubber surrounds myself for obvious reasons which were based on longevity, but you presented valid evidence for foam ones. It will take a great deal more to convince me to change my mind than just a discussion. How about it and it wouldn’t hurt to get technical. Please give your talk some meat( back up info supporting the view). Thank you!
Butyl rubber actually does not have much longevity over foam (unless in Asia). The problem with rubber is that it develops weak points over time, in which tearing occurs. The only thing that has ever outlasted most edges is ribbed paper and cloth edges. Even so, they still need to be put into servicing every 15 years, as the paper dries out. A solution is added to re-store the vitality of the edge. As far as original foam edges, most had a life cycle of about 12 years (again unless in asia). Rubber is about 12-15 years. The new foam are closer to 25-30 years. There is no such thing as a product without a lifecycle.
Some of the best speakers I've owned were foam surround. And yes - played a klf album with heavy bass and they split easily. Shame as the bass was epic. So light and agile.
A lot of plastic and synthetic materials used for electronic devices are shite and I don’t think speaker surrounds are exempt. My new JBL headphone ear pads perished in about a year. They turn into a slimey mess. The “rubberised” grip areas of my microsoft mouse because slimey. The rubber feet of my Sony Vaio computers because slimey. All seem to deteriorate just of of warranty. All have to be cleaned off and removed with isopropyl alcohol and elbow grease.
I had to replace the foam surrounds of my Duntech woofers years ago and had them replaced by rubber. Is it worth (soundwise) to redo them with the new foam?
I know the doped fabric surround on some speakers has been known to go stiff with age. I've heard people say they prefer it to rubber, but I don't know how it compares to foam.
I've had to replace my surrounds three times, the last time i used a 12 inch surround on my large Advent 10 inch woofers. Worked well , gave me a little better lows. Waiting patiently for Pauls/PS new line of speakers ;-))
@@swinde the way the woofer cone is made for the advent 10" fits perfect for the jbl surround replacement , but i listen to the 'stacked Advents' without the grills cause the 12" surrounds stick out a bit which creates the longer throw and deeper hz response...an old tweak tech.
@@doylewayne3940 Well, I still can't quite picture it. Does the 12' surround extend beyond the 10" frame of the speaker? how does it attach to the cone of the speaker? However, if it works, I can't complain.
The issue is that the modern rubber surrounds are engineered in from the start. The flexibility of the surround is well known and designed in. Foam was for the consumer, absolute junk as Paul mentioned. The manufacturers didn't much care but the consumer ended up with a mess after about 10 years. The rubber lasts very long and is a much better product. I'm using the word rubber loosely. I mean all synthetic rubbery surrounds. Synthetic surrounds are a win for the consumer!
I put older JBL control 1 speakers as distributed sound in my house. Mostly all of them had no foam left. I replaced the woofers in all but one pair and now they are falling apart as well... They were pulled from a nightclub where I installed a new sound system and were going to the dump, so the price was right.
Ah crap, you made me look. I checked an old pair of Realistic Minimus 7 speakers from ~1980 - still good. Then I checked my old Paradigm 3SE Mini from mid-80's: They are toast... :(
The Hydro-Carbons in the air can actually "melt" such Foam. Here's an a example, I was once removing a Foam Platter Mat, from an Old " AR " Turntable - the More I handled It, the More It Shrank ... Within a couple of minutes, It was a 7mm Black Greasy Ball !
The reality is that speakers have a limited life. I’ve had newish Danish speakers fail. So if your like me and keep speakers I like for many years - just hope there is a newer replacement driver available.
In the 90s.. had the Infinity Kappa 8i. Great speaker but, within a couple of years the Australian humidity did its job and a re-foam was mandatory.. Soon, as I realized this was going to come back in a short period of time,...got rid of the speakers. Great bass but, hey, there's other speakers with great bass out there, without the problem of foam deteriorating constantly.
Does anybody have tips on treatment of foam surrounds from the 80's that did survive. I have vintage Magnat speakers from the 80's and also these would suffer the same issue. However on the pair of speakers I have, the surrounds are still good. Having said that they do not appear perfect and new, they just look like something that has aged but is still fully functional. Is there a treatment to stabilize them?
utah celesta 3wy coaxes rubber suspension,carbon fiber/fabric ,rubber coated woofers bought a pair in home built cabinets in 71,they lasted to 1995,I reconed them in the same enclosures with pyle drivers bass only cones`, KLH 3wy bought a used pair,30 bucks,,they still run nicely
JBL L100s, both versions had no foam driver surrounds, but some funky thin piece of foam around the tweeter. (for God knows what?) Had mine boxed for a couple decades and decided to open them up and sure enough. A pile of foam 'sand' in the bottom of the box. eBay fix for a few bucks. After I'm dead the new owners will probably find the same thing.
@Fat Rat Just fine sir. Yes, all is well, thanks. Santa is coming in a few weeks! Tell me, does he wear red shorts and sandals in your warmer climate? 🎅🏻
Hi Paul, I have audio research speakers and replaced surrounds 5 years ago and mid speakers last year. I have found distortions in the mids that is why I replaced them. I was thinking it could be the capacitor in the crossover. Is that possible or did I get a set of bad rebuilds? If anyone has any advice it would be appreciated Thank you
Who did the rebuilds? Yes its possible you got rebuilds that are out of alignment or were not reconstructed with the proper adhesives. I also wouldn't throw out the original midranges. Their issue might not been as bad as you might thing. Capacitor will be less of an issue, but still possible. It depends on how complex the cross over is and if it has pods to control levels. Usually if you are loosing the main capacitor, your midrange will be less pronounced and not match the second cabinet. I use to work for a service shop in Los Angeles, that has been in business since 1939. Its fair to say they've pretty much seen everything cross their path.
@@TheJTcreate I have replaced my mids and crossovers as a set. They now sound as good as they did when I got them new. I am happy to say I did the surrounds on the woofers but a small shop did the mids because the voice coils were burned and I didn't think it was within my ability. They gave me my money back because you could here it on a test tone generator.
HSU Rsearch use FOAM surrounds on their massive VTF subs. They are far superior to Butyl Rubber surrounds, fast, lighter, requires less power to move to excursion limits and long lasting nowadays w/ chemical treatments
Serbia, low humidity, the speakers were always at room temperature, I never used liquids, chemicals, sponges and cloths from the kitchen and bathroom, to remove dust from the drivers....
S#@!T !! I... just replaced rubber surrounds on a vintage Yamaha Sub and I did find foam but choose to stay as factory with rubber but Im wondering if I would have had the benefit noticeable with foam instead is my thought now...
You did right. Foam surrounds on a sub will eventually lead to heartbreak, given the nature of both the driver and the surround material. The amp was built with the driver's specs in mind, hopefully. If it was originally rubber then stick with rubber.
They were a very poor choice of material. The linear (or piston) quality of the cone was compromised by lateral movement. Ozone and other contaminants in urban areas rapidly degrade the porous foam. High humidity and fungus change the characteristics. The "old-fashioned" molded treated fiber has proven to last almost as long as the speaker cabinet in the most expensive systems. The titanium diaphragms in my mid-range horns and tweeters will outlast many owners.
Every single one in the world dry-rotted at the same time. It created a wormhole and rip in the time space cigarette and now we’re using better equipment
Wel that's because you have no clue about audio period if you say that. The irs v had foam surrounds ... Pretty much every nudell in tbe higher end bracket had foam surrounds. Which by now can easily be replaced by rubber. Perhaps listen closely again to what paul said. It was the material to use at that time. You pretend it's a big deal. Takes 20 min to refoam a stack of woofer with butyl .. As I said you don't know much about audio when you say stupid shit like you just did
I replaced the foam surrounds in my 32 year old B&O CX100 that I had stored for 20 years in some box. The foam had turned into some sticky substance and just touching it softly would make it stick to my finger and make holes in the surround. After replacing the surrounds with some made of rubber costing less than US$20 they look and sound like new and now serve as my garage speakers as active Wifi speakers with Alexa voice control (added a Raspberry Pi 4 and Beocreate 4 channel amp inside one of the two speakers). Yes, I’m not doing critical listening in my garage so this is quite perfect. Giving a new life to old speakers, perhaps for that room in the house that otherwise has no audio, can be quite awesome.
I guess I was lucky enough to never see the foam surrounds break down on the genesis speakers I got for finishing highschool. I did blow one of the drivers and replaced it myself. I wish I still had them along side my Maggies.
I have four 30 year old JBLs with foam surround woofers, all still intact except for one with a tiny "dimple" that doesn't affect performance AFAICT. The E-V Interface A's I had back in the '70s into the '80s, on the other hand, had foam surrounds (on both their woofers and their passive radiators) that rotted away every 4 years like clockwork, so it seems the shortcomings of foam were already pretty much addressed circa 1990 or so, at least at JBL.
The JBL L-100 woofers used a treated cloth surround in the seventies so the woofers hold up well. However, the foam grills that came on the speakers dissolved just like the foam from that era seems to do.
Every woofer I purchased prior to 2000 has needed its foam surrounds replaced. I use kits from this source: www.simplyspeakers.com/speaker-foam-repair-new-edge-it-kits.html
"Simply Speakers" is a good, honest source for this sort of stuff -- at least when they offer replacement components that aren't actually OEM equivalents they say so, which is more than I can say for the general run of eBay sellers.
@Fat Rat hehe stones are pretty rockin! wanna test your systems true sonic power? Listen to Aphex Twin "Collapse" EP Track 2, CD or hi res. I'm not saying you're going to like this kind of music, but the engineering and how it sounds on a good system is insane. Paul needs to put it on his uncle money bags system 🤣 and crap his pants 💩🎶
We used to take uv resistant epoxy and reduce it using NAFTA, then applied in extremely thin coats over the foam. We have had great success
Yes, it has been a nice little side business, replacing old foam surrounds. I try very hard to find new formula ones when I replace them.
When re-foaming, be weary of the replacement foams thickness compared to the OG foam. Ive made this mistake recently and refoamed some woofers with thicker replacements and though I have working drivers now they dont seem to have the same excursion length as they once did : ( I believe the common term for this is "Foam Compliance"
Just refitted my old JBL LX-33's with rubber surrounds tonight (the old foam had gone brittle and cracked) - even so they still sounded great until I ripped them with a bit too much bass! :(. Repaired them tonight and can't wait to hear them tomorrow. As I understand, the rubber may sag over time, and I can always flip them upside down, but since I'm nearly 50 yrs old, hope they last me until my demise - I love repairing things rather than replacing, especially old second hand HiFi equipment that is quality and affordable (I bought the JBL's for £15 over 15 years ago and love them to bits (literally!). Thanks Paul for your excellent channel, I somehow unsubscribed a few years back, and forgot about it, but so pleased to have found you again tonight. Getting into producing music over the last year. Re-Subscribed! Best wishes to you and all at PS Audio.
Rubber or Foam?
Just be aware that replacing foam with rubber completely changes the resonance frequency, XMax, and sensitivity of the driver.
I guess the freq cut control will compensate
@@eded8045 - I’m afraid that frequency controls wouldn’t change a driver’s Thiel Small parameters.
@@petersouthernboy6327 perhaps it would be negligible to be noticeable on a sub woofer. Maybe a full range speaker or a midrange unit would be more apparent. It's Not an extreme high end system so as long as their is a nice rush of air it would satisfy most ears or chests.😋😋
@@eded8045 - if you’re happy that’s all that matters.
@Phil Allison - so why does Scan-Speak still use foam surrounds in their 32cm Revelator line of woofers?
Nice to know that long life foam surrounds are available but geez I've tossed away so much due to foam rot. It wont be easy buying anything wearing a foam surround again. Guess I'm gun shy about it now. edit: Glad you addressed this. Thanks.
Even though there have been break-throughs in modern foam technology, why the heck do JL Audio subs still kill their foam surrounds after about 3 to 5 years?
Infinity forced me to learn how to replace foam surrounds over the years.
I have 2 sets of IRS IIIa's made within a few months of each other back around 84 or 85. I had to replace the foam on one set 25 years ago but the other set is original. Weird.
I have a set of Infinity Reference 4 woofer has been reformed 2 times and mid only 1 since 1992
@Fat Rat It is odd. I'm the second owner of both sets. The set that is original foam are from the coast where I am and pretty much lived in Rec rooms and the one's that were replaced was from the middle of the country but who know where they were stored being the guy that sold them was trying to raise money to get out of jail so they may have spent some time in a storage locker. 😎
@Fat Rat It's a easy fix even so. Shame more people wont take it on.
@Fat Rat My PA subs have nice a cat piss patina on them..... 'Black Cat Moan' mojo
ahh yes. i remember the foam surrounds that degraded into sticky mess.
Thanks for your explanation. I am experimenting with a DML (distributed mode loudspeaker) approach for a sound installation in which i incorporate cymatics (visualization of sound vibrations in patterns). It might not seem pro hi-fi cause it's not. But in a sound installation for kids and students, it helps to relate the visual and auditory senses. I have a problem finding "surrounds" to test around 24 inch OD disks made of acrylic (3 mm thick), driven by exciters from the german compagnie "Visaton". I wonder if you know of a solution to make such big "foam surrounds" ? Any "H-channel" rolls ? Cause 24 inches is not available, and my project would benefit from a real surround. I'd be happy to send you pictures and videos, if this adventure seems interesting to you. Thanks for your clip. Martin Leduc, Teacher, experimenting sound art, and sound installations.
Foam has serious acoustic benefits. Better dampening and characteristics vs rubber.
One of the reasons Bose uses them, and it can cost much more to use them vs regular butyl rubber - especially when mixed with material or through manufacturing so they don’t rot.
Awesome video Paul, I loved this one. You’re one of the good ones dude, haha
I learn so much from this channel. I have been of the opinion that foam is always bad for long term use in speakers because I remember the first foam era. It's good to see that the technology has improved and we can now use quality speakers with foam surrounds again.
I bought my AR-3a speakers back in 1970. The foam failed in about 1983. I got replacement woofers from AR at the time. I then moved to Florida in 1990 and by 1995 the foam had failed again and there is a loudspeaker repair business in south Florida and they replaced the foam surrounds. 25 years later so far the new foam has not failed. I hope it is the "better engineered" foam. I also have a pair of AR-3 speakers from the 1950s with treated cloth surrounds that have never needed service for the woofers. Manufacturers used this foam for about 20 years and it apparently was breaking down in about 12 years and failing. Other things that use foam from that era also turn into powder as well.
Paul mentioned (in a talk on a different channel from about 5 years ago) that he had once _almost_ sold a synth to Walter/Wendy Carlos. Is there a place where I can hear that story or would you be willing to tell it?
I know this is WAY off topic but with 10 minutes before I have to get in the shower, then goto work, it seems like the path of least resistance to perhaps get a question/comment answered.
Thanks - ADam
I have replaced so many Foam surrounds on Cerwin Vega speakers over the years. Some of them were only a couple years old when they started to fail.
I had my Cerwin Vega AT-15’s refoamed this year. They held up well. Bought them March 1991
2 years ago I replaced the foam on my cerwin vega at-12's. It was actually a lot easier than I thought it would be and they are good as new now.
@@jmfloyd23 I love to hear others who own AT 15’s we should start a club. Still a great speaker, replacing foam surrounds not a big deal.
@@garyharper2943 Sign me up! The AT-15 is a unique speaker. They are definitely power hungry
@@jmfloyd23 Bought mine new from circuit city about 30 years ago refoamed about 10 years ago, still like new. Got them for $700 on sale and $700 was a lot of money back then.
GREAT QUESTION! One of my fave speakers had them but they degraded boxes still awesome replaced and on they go but the foam surrounds felt more delicate with the sound like the movement was effortless.
I always from first reading about their availability ( AR / EPI speakers ) wondered how close to spec are the replacements ? my guess, not very close but is it a factor ? old KLH spks used rubber coated fabric, Dynaco pure rubber I think.
Paul, Are foam surrounds less temperature sensitive for cone fs and compliance etc.?
Brings me back to rocking cerwin vega- vega series. 500 watts rms with 96 db sensitivity. I had two 15's and my buddies all had the kicker solobarics with 86 db sensitivity, and my amp just purred along nice and cool, good old school soundsteam reference 1000...Those darn foam surrounds though had to be replaced a couple times!!
I have a pair of Beolab Penta III speakers from the late 80s that need their mids' foam surrounds replaced. I recently bought a set of them and opted for the foam instead of rubber, to retain the original construction and sound. I'm hoping that this foam is new technology/material and will last a long time... I love these speakers!
what i was thinking after watching Paul
Mine disintegrated! 15 yrs of Arizona sun peeking in my living room dried them out. I kept my speakers limping along while I looked for replacements and one day the paper cones evaporated. Foam worked great, but doesn’t last.
BIC Venturi back in the day used accordion type surrounds. Why don't we see these anymore?
I remember when Butyl rubber surrounds were a major selling bullet point in loudspeaker sales when the material first came out.
@brady alex As Paul was saying, foam is pretty ideal as it's a lighter material, it holds it's shape better, and it's cheaper. But foam degrades over time especially in high humidity environments. Rubber can last forever. The minor drawback to rubber is it is slightly less flexible, it can slightly sag some over time which can affect the cone voice coil alignment and it's more expensive. The drawbacks of rubber is minor though and because it can literally last forever without maintenance it is the best compromise.
Replacing foam with rubber completely changes the resonance frequency, XMax, and sensitivity of the driver.
didn't mention that foam might sound better, but i bought rubber for durability
@@sean_heisler - rubber is fantastic, but it will raise the resonance frequency, lower the XMax, and lower the sensitivity of the driver. Just be aware of that fact when you’re going from foam to rubber.
@Fat Rat Oh, good move. That probably helped them survive in such great shape for so long! Silicon oil based products like that will keep them loose and prevent harding over time. Those were cutting edge speakers back then with the passive radiator woofers! 👍
Paul figured out to last past ps audio. His advice doesn’t degrade. 🤣
Hey Paul, I've got a pair of infinity SM-122's from 1990 whose foams are still in original and seemingly perfect condition. On Rear Surround duty right now ;)
The Pioneer FB tweeter cones from the 70’s....I can’t tell you how many I re-foamed over the years 🤣🤣.
I have a couple of beautiful 30 years old Kappa RS5 that I installed at my father's living room so he could listen his tangos waiting for second re-edging from a long time.
Also I have a couple of 1985 crappy 10" 3-way Degader (an extinted argentinian brand of cheap audio) at my garage for dayly use. Exposed to a hostile enviroment of dust and metal working and with their foams still intact, so weird! :-)))
Foam is a lighter material then rubber right ? Easier to manufacture a higher sensitivity speaker ?
People are forced to replace rotted foam surrounds in their vintage speakers, but the kits and methods vary wildly. If you don’t use foam with very similar characteristics and install them near perfectly, the results won’t be great. Compliance will change, affecting low and even mid frequencies. Best let a pro do the deed.
Yes, you want to make sure you use the proper surrounds for the speakers. But to do it yourself is not hard if only the surrounds are to be replaced and you understand to be very careful with every step. Several TH-cam videos can teach you how to do it and ideally you find the tutorial matching your exact speaker driver or a similar one, if possible.
I've repaired foam surrounds that aren't too far gone by using a two part silicon of a very low durometer, such as the brand name Ecoflex 00-30 I use. I just paint it on using a very high grade artist brush. It stabilizes the foam and stops any further degradation. To ensure good penetration of the foam, both sides should be treated. But even the outside may be enough if the foam does not have any cracks in it. If it has missing pieces then it is too far gone and a surround suspension kit must be used first. Even the replacement surround unless one of the newer high grade foams Paul mentioned should be treated to expand their life by decades.
What name of company of your subwoofer?
I have mold on my aelite 3 foam surrounding,they are older model 2006,is 2006 foam the good foam,eny tips on how to safely clean them?
so where do you buy the modern foam surrounds for infinity drivers? That last as you commented?
I bought 2 jl audio 8w3 on sale in the late 90s and opened the boxes a couple years ago. There’s hardly anything left of the surrounds and they’re unused.
Phillips ticonal 12 inch speakers has a accordion surround, still working ..made in 1956...
How about doing a comparison video on the newer foam surrounds versus butyl rubber surrounds. I prefer the butyl rubber surrounds myself for obvious reasons which were based on longevity, but you presented valid evidence for foam ones. It will take a great deal more to convince me to change my mind than just a discussion. How about it and it wouldn’t hurt to get technical. Please give your talk some meat( back up info supporting the view). Thank you!
Butyl rubber actually does not have much longevity over foam (unless in Asia). The problem with rubber is that it develops weak points over time, in which tearing occurs. The only thing that has ever outlasted most edges is ribbed paper and cloth edges. Even so, they still need to be put into servicing every 15 years, as the paper dries out. A solution is added to re-store the vitality of the edge. As far as original foam edges, most had a life cycle of about 12 years (again unless in asia). Rubber is about 12-15 years. The new foam are closer to 25-30 years. There is no such thing as a product without a lifecycle.
Some of the best speakers I've owned were foam surround. And yes - played a klf album with heavy bass and they split easily. Shame as the bass was epic. So light and agile.
A lot of plastic and synthetic materials used for electronic devices are shite and I don’t think speaker surrounds are exempt.
My new JBL headphone ear pads perished in about a year. They turn into a slimey mess.
The “rubberised” grip areas of my microsoft mouse because slimey.
The rubber feet of my Sony Vaio computers because slimey.
All seem to deteriorate just of of warranty.
All have to be cleaned off and removed with isopropyl alcohol and elbow grease.
So if I buy a refoam kit made today will the foam last longer than the original?
what im thinking as Paul claims with new tech materials
I think the best is impregnated silk impregnate the Silk with foam not sure if manufacturers are doing this, try it out Paul
I had to replace the foam surrounds of my Duntech woofers years ago and had them replaced by rubber. Is it worth (soundwise) to redo them with the new foam?
I'm gonna say: no, was flawed tech
foam surround have high speaker sensitivity.
80/90's car speaker with foam surround rot very quickly because of car heat.
Also home speakers like my Cerwin Vega VS12 (VS120 US name)
The surrounds on my 88 JBL floor speakers literally disintegrated. I replaced them a couple years ago for about $20.
What about "doped fabric" (not sure if that's the correct name) like JBL used on the 4311/12 woofers?
I know the doped fabric surround on some speakers has been known to go stiff with age. I've heard people say they prefer it to rubber, but I don't know how it compares to foam.
My Magnat speakers are still working great, they are 36yrs old (re capped of course) because they did NOT use foam. The used Butyl.
Both sets of my Dynaco speakers still have their original rubber surrounds.
I've had to replace my surrounds three times, the last time i used a 12 inch surround on my large Advent 10 inch woofers. Worked well , gave me a little better lows. Waiting patiently for Pauls/PS new line of speakers ;-))
How did that work?
@@swinde the way the woofer cone is made for the advent 10" fits perfect for the jbl surround replacement , but i listen to the 'stacked Advents' without the grills cause the 12" surrounds stick out a bit which creates the longer throw and deeper hz response...an old tweak tech.
@@doylewayne3940
Well, I still can't quite picture it. Does the 12' surround extend beyond the 10" frame of the speaker? how does it attach to the cone of the speaker? However, if it works, I can't complain.
Using foam surrounds in speakers is like using electrolytic capacitors in electronics. It works, but it doesn't last forever.
Exactly
MY AVID 103S STILL HAVE THE SAME ORIGINAL RUBBER SURROUNDS
They're made of Polyurethane foam, I think.
What about paper surrounds?
nowadays they are all siliconated synthetic rubber
The issue is that the modern rubber surrounds are engineered in from the start. The flexibility of the surround is well known and designed in. Foam was for the consumer, absolute junk as Paul mentioned. The manufacturers didn't much care but the consumer ended up with a mess after about 10 years. The rubber lasts very long and is a much better product. I'm using the word rubber loosely. I mean all synthetic rubbery surrounds. Synthetic surrounds are a win for the consumer!
Probably because they sounded like what the creators wanted, and met cost constraints.
I put older JBL control 1 speakers as distributed sound in my house. Mostly all of them had no foam left. I replaced the woofers in all but one pair and now they are falling apart as well... They were pulled from a nightclub where I installed a new sound system and were going to the dump, so the price was right.
Ah crap, you made me look. I checked an old pair of Realistic Minimus 7 speakers from ~1980 - still good. Then I checked my old Paradigm 3SE Mini from mid-80's: They are toast... :(
The Hydro-Carbons in the air can actually "melt" such Foam. Here's an a example, I was once removing a Foam Platter Mat, from an Old " AR " Turntable - the More I handled It, the More It Shrank ... Within a couple of minutes, It was a 7mm Black Greasy Ball !
The reality is that speakers have a limited life. I’ve had newish Danish speakers fail. So if your like me and keep speakers I like for many years - just hope there is a newer replacement driver available.
Great infos , thanks dear
In the 90s.. had the Infinity Kappa 8i. Great speaker but, within a couple of years the Australian humidity did its job and a re-foam was mandatory..
Soon, as I realized this was going to come back in a short period of time,...got rid of the speakers.
Great bass but, hey, there's other speakers with great bass out there, without the problem of foam deteriorating constantly.
Yah because a 15 min refoam job was so not worth it right ... God I don't envy you left-handed guys at all.
@@MichelLinschoten
15 minute refoam???
Don't you think you're a bit optimistic?
Is foam rubber different?
That makes me feel better about my Velodyne sub with foam surround😝
They rotted after 10 to 20 years depending on environment. Such a shame.
They rotted.
Does anybody have tips on treatment of foam surrounds from the 80's that did survive.
I have vintage Magnat speakers from the 80's and also these would suffer the same issue. However on the pair of speakers I have, the surrounds are still good. Having said that they do not appear perfect and new, they just look like something that has aged but is still fully functional. Is there a treatment to stabilize them?
Gewoon laten vervangen als ze niet goed functioneren heb ik bij mijn infinitys ook laten doen
I never had any foam rot on any of speakers in my life time
utah celesta 3wy coaxes rubber suspension,carbon fiber/fabric ,rubber coated woofers
bought a pair in home built cabinets in 71,they lasted to 1995,I reconed them in the same enclosures with pyle drivers bass only cones`, KLH 3wy bought a used pair,30 bucks,,they still run nicely
the answer is, they rotted away, obviously!
I had to get the surrounds replaced on my Infinity car speakers back in the 90s.
Paul, not selling anything today???
LOL
Congratulations!
Here's yer sign...
He has a PS Audio shirt on. That's advertisement...😁
JBL L100s, both versions had no foam driver surrounds, but some funky thin piece of foam around the tweeter. (for God knows what?) Had mine boxed for a couple decades and decided to open them up and sure enough. A pile of foam 'sand' in the bottom of the box. eBay fix for a few bucks. After I'm dead the new owners will probably find the same thing.
@Fat Rat
Just fine sir. Yes, all is well, thanks.
Santa is coming in a few weeks! Tell me, does he wear red shorts and sandals in your warmer climate? 🎅🏻
Hi Paul, I have audio research speakers and replaced surrounds 5 years ago and mid speakers last year.
I have found distortions in the mids that is why I replaced them. I was thinking it could be the capacitor in the crossover. Is that possible or did I get a set of bad rebuilds? If anyone has any advice it would be appreciated Thank you
Who did the rebuilds? Yes its possible you got rebuilds that are out of alignment or were not reconstructed with the proper adhesives. I also wouldn't throw out the original midranges. Their issue might not been as bad as you might thing. Capacitor will be less of an issue, but still possible. It depends on how complex the cross over is and if it has pods to control levels. Usually if you are loosing the main capacitor, your midrange will be less pronounced and not match the second cabinet. I use to work for a service shop in Los Angeles, that has been in business since 1939. Its fair to say they've pretty much seen everything cross their path.
@@TheJTcreate I have replaced my mids and crossovers as a set. They now sound as good as they did when I got them new. I am happy to say I did the surrounds on the woofers but a small shop did the mids because the voice coils were burned and I didn't think it was within my ability. They gave me my money back because you could here it on a test tone generator.
HSU Rsearch use FOAM surrounds on their massive VTF subs. They are far superior to Butyl Rubber surrounds, fast, lighter, requires less power to move to excursion limits and long lasting nowadays w/ chemical treatments
I have Kappa 6, 6.2, 8.2, first owner, foam sorrounds are like new today
Nice to hear... Which part of the world are you(or more specifically the loudspeakers) in? ....
Serbia, low humidity, the speakers were always at room temperature, I never used liquids, chemicals, sponges and cloths from the kitchen and bathroom, to remove dust from the drivers....
They might have softened up still, it will lose some mechanical resistance
@@FSXgta Possible, I don't notice or hear any difference, I'm not saying it won't fail someday, for now it's more than good.
I replaced the foam surrounds in my old AR3's in the early 80's because they got the dreaded foam rot.
Me too, effectively twice, but so far the last repair has lasted 25 years without any deterioration.
Just put butyl on it already this isn't the 70ts where rubber was stiff.
.
Had them replaced in my 30 year old Philips FB820. Like new now.
Heb ik ook laten doen bij mijn infintys niet heel duur en geven weer geluis als voorheen
S#@!T !! I... just replaced rubber surrounds on a vintage Yamaha Sub and I did find foam but choose to stay as factory with rubber but Im wondering if I would have had the benefit noticeable with foam instead is my thought now...
You did right. Foam surrounds on a sub will eventually lead to heartbreak, given the nature of both the driver and the surround material. The amp was built with the driver's specs in mind, hopefully. If it was originally rubber then stick with rubber.
@@ericbrammer3845 as I understood the new foams compared to the vintage are far superior and have less mass, hence better sound reproduction
I think Paul must have found a hidden stash of drugs, that is not a foam surround on that subwoofer.
They were a very poor choice of material. The linear (or piston) quality of the cone was compromised by lateral movement. Ozone and other contaminants in urban areas rapidly degrade the porous foam. High humidity and fungus change the characteristics. The "old-fashioned" molded treated fiber has proven to last almost as long as the speaker cabinet in the most expensive systems. The titanium diaphragms in my mid-range horns and tweeters will outlast many owners.
Refoamed my Infinity Kappa 7, 6.1, Center Video, every 10 years since 1989...
Every single one in the world dry-rotted at the same time. It created a wormhole and rip in the time space cigarette and now we’re using better equipment
‘space time cigarette”??? Well, that explains why I keep getting headaches and occasionally burned!
They sound better....just need to be replaced
What happened to foam surrounds..!!!
They got eaten by cockroaches.
I've never seen foam surrounds on any of the best speakers made today so I'm not convinced.
Wel that's because you have no clue about audio period if you say that.
The irs v had foam surrounds ...
Pretty much every nudell in tbe higher end bracket had foam surrounds. Which by now can easily be replaced by rubber.
Perhaps listen closely again to what paul said. It was the material to use at that time. You pretend it's a big deal. Takes 20 min to refoam a stack of woofer with butyl ..
As I said you don't know much about audio when you say stupid shit like you just did
ants eat them too
That sub look like rubber surrounding not foam
I replaced the foam surrounds in my 32 year old B&O CX100 that I had stored for 20 years in some box. The foam had turned into some sticky substance and just touching it softly would make it stick to my finger and make holes in the surround. After replacing the surrounds with some made of rubber costing less than US$20 they look and sound like new and now serve as my garage speakers as active Wifi speakers with Alexa voice control (added a Raspberry Pi 4 and Beocreate 4 channel amp inside one of the two speakers). Yes, I’m not doing critical listening in my garage so this is quite perfect. Giving a new life to old speakers, perhaps for that room in the house that otherwise has no audio, can be quite awesome.
LOL - Replacing foam with rubber completely changes the resonance frequency, XMax, and sensitivity of the driver.
@Fat Rat - oh he edited the crap out of his original post
I guess I was lucky enough to never see the foam surrounds break down on the genesis speakers I got for finishing highschool. I did blow one of the drivers and replaced it myself. I wish I still had them along side my Maggies.
cats and foam surrounds do not mix well
Hey Paul you stoled my belt
I have four 30 year old JBLs with foam surround woofers, all still intact except for one with a tiny "dimple" that doesn't affect performance AFAICT. The E-V Interface A's I had back in the '70s into the '80s, on the other hand, had foam surrounds (on both their woofers and their passive radiators) that rotted away every 4 years like clockwork, so it seems the shortcomings of foam were already pretty much addressed circa 1990 or so, at least at JBL.
The JBL L-100 woofers used a treated cloth surround in the seventies so the woofers hold up well. However, the foam grills that came on the speakers dissolved just like the foam from that era seems to do.
Every woofer I purchased prior to 2000 has needed its foam surrounds replaced. I use kits from this source: www.simplyspeakers.com/speaker-foam-repair-new-edge-it-kits.html
"Simply Speakers" is a good, honest source for this sort of stuff -- at least when they offer replacement components that aren't actually OEM equivalents they say so, which is more than I can say for the general run of eBay sellers.
NICE!!
interesting
What happened to foam surrounds? They cracked and blew out, feel like reminiscing? go down to the local Goodwill.
@Fat Rat lol usually too dried out. Never ran into sticky ones personaly in my thrift store quests.
@Fat Rat sticky fingers, right 😚💨🥴
@Fat Rat hehe stones are pretty rockin! wanna test your systems true sonic power? Listen to Aphex Twin "Collapse" EP Track 2, CD or hi res. I'm not saying you're going to like this kind of music, but the engineering and how it sounds on a good system is insane. Paul needs to put it on his uncle money bags system 🤣 and crap his pants 💩🎶
@Fat Rat lmao I will check those tracks and check my pants after 🙊 thanks!
First?