Rubber surrounds on 12" Infinity woofers?

goodolpg

Just an old fart trying to help.
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Another question based on posts elsewhere on AK.
A member has a set of RSM's bought new around 1980 or 81, never been worked on (I think) and they have rubber woofer surrounds.
He was checking out another pair of RSM's in his area and they have rubber woofer surrounds as well.
The 5" midranges all had rubber surrounds, I'd just not heard of woofers with rubber surrounds.
Anyone else have or seen Infinity 12" woofers with rubber surrounds (RSM's in particular)?
Just curious as I like when I learn new stuff about vintage (and RS series in particular) Infinity products.
Thanks.
 
Hello I didn't know they used rubber surrounds that early on. My Kappa 8.1s seem to have a rubberized foam on the mids and woofers but they were made in 1991-93 . The Renaissance series I believe had them as well plus most of the line after 1995.
 
The ren's are not rubberized foam, they're rubber (and apparently completely un-replaceable if destroyed, a 10" watkins just doesn't exist anywhere else)

the kappas, .0 and .1 are foam. I have owned some from every line, (kappa 9.0, 8.1,7.1,6.1, Ren 90) and still have the 8.1 and ren 90(as well as infintisemals and rs 4) to directly compare, and they are totally different.

I need to go look at the pair of Qa I've 'loaned' out, but my recollection is rubber, with the grey doped paper woofers. That's from (faulty) memory, so take it as you will.
 
Thanks for the input.
I know Q series had rubber.
Just have never heard of RS series using rubber.
The poster also has vinyll covered cabs, I thought RS series all had oak veneer.
I think he has some very unique models based on what he has said.

Here's the thread, we got talking about RSM's in it.
http://www.audiokarma.org/forums/index.php?threads/infinity-rsa-and-qb-trash-picked.780312/

Note--in another thread a couple years back E-man (from Aus) was telling of his RSM's which have vinyl cabs and mirror image driver arrangements. Didn't ask if his had rubber woofer surrounds.
 
The ren's are not rubberized foam, they're rubber (and apparently completely un-replaceable if destroyed, a 10" watkins just doesn't exist anywhere else)

Over the last few years, I've toyed around with various butyl rubber surrounds on Infinity drivers, namely the 12" Watkins woofer and the 10" clear poly woofer from the RS-IIIa/RS-II/etc. Different surround yield different results- the surrounds I put on the woofers that will go into my RS-IIIa's change the parameters by increasing the weight of the surround compared to the foam original (another discussion for another day). The surrounds I put on my RS-II woofers match the paramaters of the original foams almost exactly, but the small contact area is not desirable, so I will probably change them eventually. Anyway, I bought them all from China, and I might have saved that seller in my ebay seller watch list; he had tons of butyl surrounds of various types. I'll bet if one searched enough, a decent replacement could be found for those 10" Ren 90 woofers or 8" Ren 80's. Would take a lot of experimentation though...buy, install, test; buy, install, test; buy, install, test. What a pain! Same for the woofers in the IRS Sigma, Epsilon, and Omega. Can't think of any other legacy Infinity's off the top of my head that had butyl surrounds. You'd have to know the parameters of the originals; For the Ren's and IRS Omega, any variation off the original resonance frequency would throw the tuning of the second voice coil (the Watkins circuit) and create a possible impedance drop.
G~
 
The ren's are not rubberized foam, they're rubber (and apparently completely un-replaceable if destroyed, a 10" watkins just doesn't exist anywhere else)

the kappas, .0 and .1 are foam. I have owned some from every line, (kappa 9.0, 8.1,7.1,6.1, Ren 90) and still have the 8.1 and ren 90(as well as infintisemals and rs 4) to directly compare, and they are totally different.

I need to go look at the pair of Qa I've 'loaned' out, but my recollection is rubber, with the grey doped paper woofers. That's from (faulty) memory, so take it as you will.

Hi jazzy good to know. I wasn't sure what they were made out of since they were still in good shape.
 
I'm not sure but I think someone here sent some ren-80 woofers to millersound and he redid the rubber surrounds, I think they can be redone back to original if damaged.
 
I could swear I saw in the last 2 or 3 months where one of the acknowledged experts, either MillerSound, or Mr. Watkins, that said the rubber surrounds on the 5" Watkins drivers are very difficult to replace. I got the impression they don't even want to do it.
Something about centering the voice coil or similar.
I know some (all?) of the Q series used rubber surrounds.
I wonder if Infinity changed to foam due to audible or cost factors.
Another thought, the person in the other thread is seeing these rubber surrounded RSM woofers in his area, rather than OEM, is it possible there is a speaker repair shop in that area that changed rotted foams for rubber?


EDIT---7-31 Here's the comment about rubber surrounds by one of the acknowledged experts...
HiFiAarons post

http://audiokarma.org/forums/index.php?threads/infinity-renaissance-80-styles.767758/page-4
 
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I'm not sure but I think someone here sent some ren-80 woofers to millersound and he redid the rubber surrounds, I think they can be redone back to original if damaged.
Recently, a member had a rubber surround with a rip/tear and sent it out for repair, could that be the one you are thinking of?
 
Yes, the gentleman in Utah with the newly found pair. But I could see a repair shop using rubber on 12" woofers if that's what they had on hand.
 
the kappas, .0 and .1 are foam. I have owned some from every line, (kappa 9.0, 8.1,7.1,6.1, Ren 90) and still have the 8.1 and ren 90(as well as infintisemals and rs 4) to directly compare, and they are totally different
The 8.1s (and probably 7.1s) are foam but it's a different formulation than what was used on other Infinities. My 8.1s, 7.1s and SSW-210s (which use the same woofers as the 7.1s) all have the original foam which shows no signs of deterioration. On the other hand, on both my pairs of 6.1s and all my Kappa Videos and earlier Kappas, the foam had completely deteriorated.
 
On my 8.1's and 7.1's the foam was replaced four or five years ago, because it had failed completely.
Same on my CS 3009s (both pair) and 3007's (both pair)
 
Qb's have rubber surrounds on their 10" woofers. Every 12" Watkins I've seen have foam. I've heard that rubber cost you about 3 db.
 
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