Isn't refoam enough? basic restoration question

[Steve K]

Hello, everyone. I've read most posts on refoam/recone, and I see that most people are satisfied with just refoams. What I'd like to know is - when is reconing actually necessary then? I was talking to this service repair technician who owns an independent authorized repair shop for JBL, as well as other makes, and he told me that with older speakers, refoaming is not just enough as the DAMPER (I'm not yet familiar with all the terminology) that's between the cone and the coil unit, gets 'tired' with usage as with any moving parts and need to be replaced, too. Can anyone elaborate on this? I'm thinking of refoaming the woofer, and possibly the PR, on a L220 that I recently acquired, and would like to know if reconing would be really worth the higher cost. Thanks in advance.

[Don C]

I think that your tech is referring to the spider. I think that the spider lasts longer than the foam does, so maybe a recone is not really needed when the foam fails, especially the first time the foam fails. But the recone kits are not going to be available forever, so when the kits are available for older models like your L-220, I think that they are a good investment. You might not notice a big change from reconing now, but you may be extending their life for years.

[Oldmics]

Hi Steve K

Refoaming a speaker is a repair that takes into consideration only the outer edge of the cone,commonly called the surround.The surround deterioates for a varity of reasons but mostly due to age.

As you are aware the surround is not the only alignment,attachment point.

The item you are calling a "dampner" is the spider assemble.The spider is glued to the bottom of the cone,the speaker frame and also to the voice coil assembly.The spider is subject to a loss of compliance over time due to many reciprocating motions of the cones movement.

Loss of compliance in the spider is what your JBL spokesman is informing you of.

Now,speaking strictly as JBL policy is enforced,refoaming is NOT an authorised JBL repair.

JBL feels that when the foam surround has deterioated that the spider has also run thru its lifespan.At such a time the entire assembly should be replaced.JBL recommends that a recone kit be installed when these types of failures occur.

However,If a refoam is to be a consideration.

Then a through inspection of the spider for sagging suspension,tinsel lead attachment points (look for corrosion),voice coil D.C. test and a general all over inspection should be preformed before a refoaming job is decided upon.
These are all items that a competent reconer will inspect before suggesting refoaming or reconing.You gotta find a guy that you can trust.
Refoaming is not all that difficult but replacing a worn spider is a bit tricky.Sourcing spider parts may also prove difficult.Foams and spiders are not availiable from JBL.These come from generic parts suppliers.

If a spider and surround need replacement ,usually a recone is in order.

Same stress points for the passive radiator (spider and surround) should be inspected.

Hope this long winded message is helpful.

Oldmics

[Mr. Widget]

Due to the mass of the heavy cone assembly of the LE14A used in the L220, the likelihood of the spider being worn out is higher with this woofer. If you can afford it it is typically best to due the full recone especially with the LE14A. You will certainly see an improvement with a simple refoam though.

Widget

[Steve K]

Thank you, all, for the replies.
Now, if I can only figure out a way to afford the repair! Over here in Japan, repair shops charge about a $100 for each recone and JBL's original recone kits cost around $250 (at least, the JBL affiliate here seems to have plenty of those in stock), but the PRICE!!!

[JBL Dog]

Hello, everyone. I've read most posts on refoam/recone, and I see that most people are satisfied with just refoams. What I'd like to know is - when is reconing actually necessary then? I was talking to this service repair technician who owns an independent authorized repair shop for JBL, as well as other makes, and he told me that with older speakers, refoaming is not just enough as the DAMPER (I'm not yet familiar with all the terminology) that's between the cone and the coil unit, gets 'tired' with usage as with any moving parts and need to be replaced, too. Can anyone elaborate on this? I'm thinking of refoaming the woofer, and possibly the PR, on a L220 that I recently acquired, and would like to know if reconing would be really worth the higher cost. Thanks in advance.

Tough call on the L220. It is my understanding the LE14A cone kit is now obsolete. You may want to go ahead and get them reconed if you can find kits. I'm not sure if anyone makes an aftermarket kit. Good Luck!

[boputnam]

For Steve K

I'll see if I can find the Link to the whole brochure for you...

It's in the Library (http://www.lansingheritage.org/html/...l/1975-sum.htm), from where you can piece-meal download the manual page-by-page and re-assemble in Adobe Acrobat.

[4313B]

It is my understanding the LE14A cone kit is now obsolete.

It appears Pro has a few left. I'd get them while they're "getable".

[Steve K]

Really appreciate the posts to my basic inquiry.

'Boputnam' --> I found your reference to the Library photos very educational. I can now speak with a service technician with a little more confidence.

'Giskard' --> Hmmm, I suppose you're suggesting that, if those cone kits are still available from repair shops here, that it would be worth it to invest in them now lest they really become 'extinct' in the foreseeable future. I checked the JBL Pro website and saw that they only sell to 'authorized service accounts.'

Thanks!

[pmakres1]

It appears Pro has a few left. I'd get them while they're "getable".

I was able to get the kits for my L220's LE14H's a couple of years ago from JBL Pro. I did have to wait for the next production run at that time. I agree with Giskard, it's definitely a good long term investment.

Good Luck!

Peter M.

P.S. Yes, it is likely you'll have to go through an authorized JBL center, as I did.