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Anton
05-06-2003, 06:49 PM
In my previous message I said the sound I get from
my system 2235,2123, 2420, sounds great .
For the heck of it I ran a audio generator test
and was a little dissapointed that the 2235 was
not responding in the lower 50 to 30 hz range
as I figured .
The 2235 had been refoamed by a reputable person
could it be it is too stiff and needs time to
break in . the 2123 were brand new units .do they
also need time for breaking in

Thankyou

jblwolf
05-06-2003, 08:57 PM
I have refoamed many JBL speakers and yes there is a break in time,it also makes a differents what the surround is made of/condition of the spider,I have seen many different types of surrounds some very thin(looser),some much thicker,the thicker(stiffer)the surrond the longer the break in time,20-25 years ago it was tuff to find replacement surrounds so you had to use what you could find,now there all types of choices and at a cost of less than $5.00ea I can afford to buy different styles/thickness to see what fits/works best,I had a pair of LE15 that really started to sound good after about 100 hours of use,right after the refoam they had good bass,but now they really kick out the bass:D -Wolf

Anton
05-07-2003, 12:01 AM
It seems that the surround and the spyder seem to be
kinda stiff and I had a hunch they might need some time to break in
Long ago I remember reading where someone was building a small sytem and he
sat the 6" speaker on a bench and ran 60 hrz thru it
for over night .
Thanks for the Info

Rolf
05-07-2003, 01:18 AM
Hi.

I really dont't understand why you refoam. Why not re-cone? This is the only thing JBL recommend. You don't really know the condition deeper inside your speaker???

And yes...they need a 100-200 hours to play good.

Rolf

jblwolf
05-07-2003, 10:42 AM
ROLF,to answer your question,1-is cost 2-keeping the original as original as can be kept original, 3-in my opinion the vintage parts are better than the replacement.that is if you can find the right replacement at all,I'm a big fan of the le15a and I have seen and heard what JBl and others calls their replacement kits for this model, (in my opinion) it does not meet the old standard,as for JBL recommends:rolleyes: they love selling cone kits and no one can do it better than they can:rolleyes: ,I have went as far as ordering new spiders,so I could use the original coil/cone-call me crazy or a original parts freak,but to me vintage is vintage and you cant replace that quality-I wonder how much it would cost to build a LE15 today at 1960/70's standards?or for that matter a Mcintosh or a Fairchild 100 watt tubeamp?I would even bet that alot of the home driver kits are no longer available,they may have what they call a equivalent(pro model kit)but is it the same as the original?:confused:-Wolf

Earl K
05-07-2003, 11:45 AM
Hi Wolf

Originally posted by jblwolf
1-is cost 2-keeping the original as original as can be kept original, 3-in my opinion the vintage parts are better than the replacement.:-Wolf
I must follow your #1 guideline since parts cost in Canada track our exchange rate. That doesn't make for a pretty "cost of repair "picture. I also follow your points #2 & #3 to various degrees . I agree, that if a cone & coil are in decent shape, why trash it ? This old le stuff deserves better than that if it can be saved . I refurbish the old Lansoly surrounds on le10s & le14s but haven't yet gotten into having spiders changed. I'd like to pursue that at some time soon . I have a few questions about swapping out spiders .

I don't want to become a reconer, but I will dabble in "triage", getting the patient prepped for my local reconer to center-up & glue .


Is this spider changing something you've personally done , or was it done by someone else ?

How does one get an old spider off of the voice coil without leaving the old spiders' glue line ? ( this question also applies to dustcaps )

Are there specific solvents that will do this for the old & new style JBL glues .

Are these solvents harmful to other parts of the assembly ? ie papercone , coil former , surround , etc.

If you were planning for future - refits , is there an alternative type of glue to use that's easier to remove ?


Thanks for any answers to the above <> Earl K

4313B
05-07-2003, 03:32 PM
Long ago I remember reading where someone was building a small sytem and he sat the 6" speaker on a bench and ran 60 hrz thru it for over night .

Never set a JBL transducer with a vented pole piece flat on a bench for break in.

I usually break in a transducer such as the 2235H for 4 hours at 20 Hz. This is sufficient to drop the Fs 6 to 12 Hz and all is well once that occurs.

4313B
05-07-2003, 03:40 PM
For the heck of it I ran a audio generator test and was a little dissapointed that the 2235 was not responding in the lower 50 to 30 hz range as I figured .

Well, after breaking it in see how it sounds. It could be the compliance of the new surround doesn't meet spec and you are SOL. Fairly large shifts in compliance can be acceptable but too much can be quite undesireable.

luxmanlover
05-07-2003, 05:07 PM
How much power do you apply to the transducers while they are in break in?
Kelly

4313B
05-07-2003, 07:23 PM
10 volts at 20 Hz for the 2235H.

jblwolf
05-07-2003, 07:36 PM
Earl,yes,I have did the spider replacement myself and many other repairs,I would recommend taking it in,my background goes back more than 25 yrs, when I had the opportunity to work at a local JBL dealer as a tech(he even paid to send all techs for training@JBL and tickets to the US fest too boot in the early 80's)and learn most of the repair techniques that a local dealer would be set up to do,I'm way passed that point now,I even ordered throats for 375 drivers,thinking I could repair them but enough is enough but I still may try it:eek:,the damaged 075's I rebuilt work just fine but it really should stop somewhere.but getting back to having the know how,parts will be hard to come across,years ago JBL would sell spiders to their dealers for that repair(JBL may say they dont but they did),but now?same goes with surrounds,I had to shop at least 4 different places to get the right size surround for the 136's and the le15's,and when it comes to the le14 thats another story.just as never cutting off the dust cap then you replace the surrounds-to this day I never needed to take the dust cap off for replacing just the surround.then there the glue,I only use 2 types- both came from JBl in tube/bottle form, I had a good suppy,Im down to my last 10 or so that I had for years,ones blk - the other brown,I use lacquer thinner-Qtips for all the clean up of old or new glue-learning on vintage equipment I feel should at some point be left to the pros :) ----Wolf

4313B
05-07-2003, 07:59 PM
Hi guys,

MEK (Methyl Ethyl Ketone) is the "official" solvent used to remove the brown JBL glue (Bostic). You can pick it up at any good hardware store. Don't get it on the foam surrounds, they will expand and sometimes won't go back to normal after drying, especially if you touch them or fuss with them while wet.

http://www.nsc.org/library/chemical/Methyl_E.htm

Rolf
05-08-2003, 12:39 AM
Hi. Cost I can to a certain point understand. Keeping it as original as possible? Well ok, guess it it like having a veteran car. BUT to say that the cone of a 2235H is not as good as the original 2231A cone, well, I not sure about this. Maybe Giskard knows.

Anyway, with repect, it seem to me that it is not the sound quality that matters, but to keep the speakers in the most original condition.

I use my 4333A's for music, and want them to sound best possible. That is why I change and modify them.

Rolf

Earl K
05-08-2003, 05:15 AM
Hi All

Thanks for the answers guys.

Does MEK dissolve the "Black" JBL glue ?

regards <> Earl K

4313B
05-08-2003, 07:04 AM
"BUT to say that the cone of a 2235H is not as good as the original 2231A cone, well, I not sure about this."

The 2235 cone is superior to the 2231 cone. It offers increased linearity and control. It's one of those evolutionary improvements in LF transducer technology John Eargle refers to.

Arguably the best cones were those made by Hawley before it's demise. Hawley has since resurfaced but I don't know if they have a relationship with JBL anymore.

If one prefers the sound of the original LE15 cone assembly to the current LE15 cone assembly who can argue? :)

"Does MEK dissolve the "Black" JBL glue ?"

Yes, I've been told the black glue is dyed Bostic. We carefully paint the brown Bostic black to match the dyed factory Bostic after finishing a recone. The recone kits only come with tubes of brown Bostic.

"as for JBL recommends they love selling cone kits and no one can do it better than they can"

I'm pretty sure JBL would just as soon ashcan all the old cone kits. They're a pain in the ass. To sell spiders and foam surrounds would further compound an already precarious issue. Frankly, I'm awaiting the day JBL simply marks all these kits NLA. This is just my perception and I could have it all wrong but more than a few have already been so marked. A full recone is expedient and cost effective from a labor standpoint. Plus it is an integrated fully functional unit. Few people can handle refoams let alone spider replacements. Look at all the crap on eBay with their amateur refoam jobs. I understand the premise and support it in theory but the current level of expertise generally isn't there and JBL doesn't appear to be all that fired up to rectify the situation. Basically, the deal is, if some fifteen year old kid wants to buy a refoam off ebay and "do" his "old" LE10's in his dad's hand-me-down L96's nothing is going to stop him. Unfortunately the rest of us have to suffer viewing the crap when it surfaces on ebay. Then a full recone is the only option because the refoam job was such a hack.

locanti
05-08-2003, 07:31 AM
Originally posted by Earl K
Hi Wolf

I refurbish the old Lansoly surrounds on le10s & le14s



Hi Earl

I'd heard once about refurbished LANSALOY surround but always wander how it can be done.Do you use some Brake-oil or thinks like that and is the result to your wishes with LE10A and LE14S?I have to change surrounds on a pair of LE10a unless their still in good shape but sticky.:confused:

4313B
05-08-2003, 07:52 AM
Just an FYI

Lansaloy is a petro-chemical organic based compound that will deteriorate over time. Minimizing its exposure to moisture, temperature, ultra-violet light and atmospheric contaminants (smoking for instance) will prolong it's life.

JBL replaced Lansaloy free of charge up until the warranty on the very last of the Lansaloy transducers ran out. (Actually they extended that warranty until the mid 80's as a good will gesture)

Lansaloy is awesome when new. It's junk soon after if not taken very good care of. I think Earl's work in figuring out a way of restoring it is commendable!

Earl K
05-08-2003, 08:39 AM
Thanks Rob

I do agree with you that full reconing is the way to go.

2235 cone kits are presently a bargain ( IMHO ) , and their price seems to reflect a JBL commitment to a current supportability. The le series doesn't appear to enjoy the same status. Though, it's arguable that any perception of lessening JBL support for the le series is just a bonafide reaction to disappearing consumer demand . Too bad this is when I'm discovering these "white" Aquaplas wonders . :) Hence my accumulation. :p

<> Earl K

Rolf
05-08-2003, 09:13 AM
Yes! I guess Giskard's input makes the point.

My own experience is that after I got my original 2231A's woofers re-coned with the 2235H re-coning kit, I could hear a clear difference...for the better.

So you guys who wants to keep you speakers as original as possible : OK! .. but you don't want your speakes to sound at their best.

Do you agree???

Rolf

4313B
05-08-2003, 10:27 AM
"So you guys who wants to keep you speakers as original as possible : OK! .. but you don't want your speakes to sound at their best."

Well, let's take a 4331 and a 4430. Regardless of anyone's opinion, the 4430 is by far the superior loudspeaker. That isn't an opinion, it's a fact. Everything about the 4430 reeks of superior engineering as compared with the 4331.

Now, plug the 4430 and the 4331 into an amp and play some recorded music through them both for a group of people and there very well may be some who prefer the sound of the 4331 over the sound of the 4430. That's opinion based on perception. Going further, a particular person may conclude that certain material may sound better on the 4331 and other material may sound better on the 4430. And what a person finds to be the most pleasing listening experience is all that matters in the final analysis regardless of which loudspeaker is the "superior" loudspeaker.

Despite all that, I still shake my head in complete bafflement when someone says they prefer Klipsch or Bose :p I suppose if I soaked my head in a vat of animal fat for a day I might be able to change my perception sufficiently to prefer Klipsch or Bose too?

D'Oh! :p :p :p

I just amuse myself endlessly...

Mr. Widget
05-08-2003, 10:36 AM
Now, grouping Klipsch and Bose? You are being a little hard on Klipsch.

4313B
05-08-2003, 10:45 AM
My intent was to be a little hard on Bose :D

Mr. Widget
05-08-2003, 12:05 PM
Oh, I see.:) :)

4313B
05-08-2003, 12:50 PM
I definitely get your point though Rolf. I like to upgrade and improve my systems whenever some new idea comes along. I've owned many JBL's over the years and some I simply didn't want to upgrade or improve because I felt they were dead ends. Others that have fallen by the wayside I think I would like to revisit and try new things with.

I will try to get to the 1.55mH tapped autotransformer solution this weekend. G.T. found one and sent it out to me to measure, I've just been putting it off because it's a bear to do. You know, it's the old "first one is a challenge, second one is a chore" thing. BTW, I've noticed that JBL might have "found" a bunch of old parts. It appears many of the 4430 and 4343 network parts are available again... Have you given any thought at all to adding a 2121/2122/2123 to your 4333's? Currently it costs half as much to build a 2121 or 2123 as it does to build the awesome 2122 (naturally :rolleyes: ) but that's cool because you would most likely want to build a 2121 anyway.

Earl K
05-08-2003, 01:54 PM
Hi locanti


Originally posted by locanti


I'd heard once about refurbished LANSALOY surround but always wander how it can be done.Do you use some Brake-oil or thinks like that
Yes, DOT 3 (FORD type ) Brake Fluid softens up hardened Lansaloy. DOT 5 (GM type ) doesn't react with the LansaLoy but has other uses in a complete surround restoration. ONE lightly painted on application of fluid ( to the back of the le10 surround ) will drop the Fs of a petrified surround down about an octave ( Fs is usually about 120 hz when the surround is completely dried out ) . It hits 60 hz in about 12 hours . A wait of 48 hours is highly recommended to make sure the drop in Fs has actually leveled out . Fs should be monitored on a regular basis - like every 6 to 8 hours for this very first application. If a person can't measure Fs, then doing a second application is flirting with disaster because you can go too low ( loose ). All these old le10 woofers will have flimsy / loose spiders by this point in their lives. The flimsier you make the surround/ suspension , the more that old, tired spider has to work at keeping the coil centered. Loose surrounds will easily equal "scraped voice-coil". Then you must recone anyway. A single little bit of brake fluid will stain the aquaplas. I thought I was washing my hands enough but apparently not. Sort of like ; eating peanuts, washing up , sitting down to read a glossy magazine and finding you are still leaving fingerprints on the pages .
If a second application is made then Fs monitoring should be done more frequently. Say, every 4 hours. The amount "applied" should give the untreated surround - a wet leather look, but not a "soaked to the skin leather" look . ie; One shouldn't be able to see any glossy sheen. That's TOO MUCH fluid. Wipe some off with a paper towel . It pays to be patient with this stuff and apply fluid in smaller increments over many days. But if you can't measure Fs , then this is all just a roll of the dice. Who knows where you started and where you'll end up? A brake fluid surround will also eventually start to dry out ( months, not years ) - so these treatments shouldn't be considered as permanent fixes. The newly "ruptured- but treated" LansaLoy will dry out faster than the original time period. This is another reason why a full recone from the start is the best way to go . I've worked on a coating goop to keep the DOT 3 from evaporating out of the surround. It involves DOT 5 fluid and silicone mixed together. This step is even trickier to implememt . Since it locks in the established Fs, if a person can't measure Fs , then ignore the thought ..


and is the result to your wishes with LE10A and LE14S?

Yes the results are satisfactory. But it's not a simple procedure. The le10 surround is quite thin.Because of this, a drop in Fs below 30 hz will result in the LansaLoy actually ballooning " twisted balloon-like " as the LansaLoy continues to expand past its natural point of shape retention. The cells of the surround are actually ruptured by the brake-fluid and then the surround continues to drink & drink till it "hurts itself" . The Le14 which has a thicker surround is not nearly as prone to these problems .


I have to change surrounds on a pair of LE10a unless their still in good shape but sticky.:confused:

Well , here, I'm confused too . Always best to have a Pro evaluate the woofers condition ( that would involve, at the very least, an Fs measurement , a visual inspection and a proper tone sweep - would be nice to get an impedance curve ). Again, a recone is a lot easier .

regards <. Earl K

Rolf
05-08-2003, 02:04 PM
Can I build a "box" with the midrange woofer, and put it on the top/beside/under my 4333A's?

Rolf

John
05-08-2003, 07:45 PM
What type of glue is used to secure the spiders to the voice coil former in the LE-15A woofer??? Is it a type of epoxy???

Guido
05-09-2003, 01:51 PM
Originally posted by Giskard
Currently it costs half as much to build a 2121 or 2123 as it does to build the awesome 2122 (naturally :rolleyes: ) but that's cool because you would most likely want to build a 2121 anyway.

Hi Giskard!

Could you explain me that? The recone sets costs all the same and the baskets are heavy to find even in Germany.
How the hell should Rolf find one in Norway?

Rolf
05-10-2003, 03:12 AM
Originally posted by Guido
Hi Giskard!

Could you explain me that? The recone sets costs all the same and the baskets are heavy to find even in Germany.
How the hell should Rolf find one in Norway?

Hi Gudio.

Do you mean recone kits to JBL woofers???

Rolf

Guido
05-11-2003, 04:25 AM
@ Rolf

Of course you can find recone kits in Norway!

But the 2121, 2121H or 2122H is very hard to find.

Guido

Rolf
05-11-2003, 04:38 AM
Of course you can find recone kits in Norway!

But the 2121, 2121H or 2122H is very hard to find.

Guido

Hi GUdio

If you mean the basket/complete speaker, I don't really know. I have never tried to find one. But remember, from the late 60's and to the mid 80's there was sold quite a lot professional JBL's in Norway.

I an trying to get my hands on 4350 or 4343, but so far no luck. I would perfer if they are somewhere in Europe, as I expect quite a freight bill to get them from the US.

Can you recommend good European sites where used hi-fi is sold?

Rolf

Guido
05-11-2003, 03:13 PM
Hi Rolf!

I bought my original 4343 cabinets + 2420 drivers incl. horn + X-overs original + 2405 slot tweeters original from www.ebay.de.

The only things missing are pair of 2235H (2231A) and 2121 or 2122.

But I'm shure I will find them soon. I'm on a few tracks.

I can't wait to hear my 4343.

Guido

Niklas Nord
05-12-2003, 07:45 AM
Giskard how do you break in the drivers?
20hz at 10 volts you say, with an ampfilter
and test tone ?

or some instrument?

4313B
05-12-2003, 08:23 AM
Yes, an amplifier, an audio oscillator, and a volt meter.

locanti
05-13-2003, 09:07 AM
Originally posted by Earl K
Always best to have a Pro evaluate the woofers condition ( that would involve, at the very least, an Fs measurement , a visual inspection and a proper tone sweep - would be nice to get an impedance curve ). Again, a recone is a lot easier .

regards <. Earl K [/B]

Thanks Earl for your advice

It's not so easy to have an expert opinion here in France.Dealers just want to sold you new loudspeakers even if yours are still usable.So we have to do business by ourself.

I'm an electronician(Work in a phone company)and I recone loudspeakers for years(When I found the recone kit)I have the equipment to measure FS and to draw an impedance curve.( sound generator,Impedancemeter,oscilloscope and more)

The 2 Le10A have an FS of 83HZ an 96,5Hz.I used them in C53 libra cabinet(Copy) and the sound have no bass at all(It seems to me than few years ago the sound was deeper) :rolleyes:

Does it worth the money to recone them?

Regards

Bert

Earl K
05-13-2003, 11:20 AM
Hi Locanti


Originally posted by locanti

The 2 Le10A have an FS of 83HZ an 96,5Hz.I used them in C53 libra cabinet(Copy) and the sound have no bass at all(It seems to me than few years ago the sound was deeper) :rolleyes:


The Fs on those speakers should be 30 to ( 40 hz on the high side ) for arguments sake. You will certainly not be getting the bass you used to get with Fs values that high. Try , one ( time only) DOT 3 brake fluid treatment to see where the Fs ends up .



Does it worth the money to recone them?


Try the brake-fluid method first with the thought that if you mess it up and it doesn't work out , then you must spend the money on the recone kits .
I happen to like the aquaplas dampening of these speakers so much that I'm likely to buy a pair of recone kits to keep around for the future upgrades & projects . But, at only @ 90 db/watt you have to answer that question of accumulation for yourself. I'm using these with the less sensitive le14 woofers. A lot of others prefer to build projects that are mid 90 ( db ) effeciencies using 2235s/ 2245. That dictates going to the 2121, 2122, 2123 range of 10" midrange speakers to match sensitivities. I'll probably order some kits after the Canadian dollar strengthens some more against the US dollar . Right now the Euro $ is in good shape vs the US $ so maybe nows a good time for you to order. Predicting currency exchange rates is virtually impossible ( if one could, some of us would be rich )


Regards <. Earl K

locanti
05-13-2003, 12:19 PM
Hi Earl

I suppose it's easy in US to find replacement kit for JBL Le10 drivers but in Europe it seems that only the professional series speakers kit are available.Where can I found kits on the Web?Do you know some shop that sell overseas?:confused:

Doctor_Electron
05-13-2003, 12:48 PM
Yet another Dr_Electron-length post...
I worked for a JBL pro service center, and would like to share with you what you get for your $$ on an authorized re-coning.
My personal involvement in the process (on other than my own components) mainly consisted in cleaning the frames and checking them for gap cleanliness & gap concentricity/width, as the owner was very particular (nearly to the point of obsession, partly a control freak issue, partly a perfectionist issue) about re-cone jobs being properly done there.
The re-cone starts with removal of all the old cone/spyder/surround residue & glue from the woofer frames (yes, MEK is the ticket, although it barely fazes the newer epoxies, as found on the 127H, etc.), Lots of elbow grease and very sharp chisels & bearing scrapers seem to be all that works on them.
The voice coil gap must now be perfectly clean, and is checked with the appropriate gap gauge (non-magnetic beryllium/copper or martinsitic stainless steel, JBL part #, $$).
Now a JBL factory recone kit is installed via the use of an alignment tool in the form of a thin but very rigid plastc cylinder, which is placed squarely in the magnetic gap. The cone /spyder assembly is then slid over this cylinder, and the spyder is glued, followed by the gluing of the cone surround to the frame. While the glue is not quite fully hardened, the new cone's voice coil is carefully moved in and out of the gap to check for rubbing. Once this alignment is adjusted and checks out OK, the glue is allowed to harden, after which the alignment cylinder is removed. The dust cap is glued onto the cone, and the voice coil's "tinsel leads" are soldered to the connector posts. Following this, another "externally applied" (by hand, that is) cone motion re-check must be done (no VC rubbing again), and finally the driver gets a short series of impedance, frequency sweep, and electromechanically applied motion & response tests.
What I would consider a proper cleanup on a 2235, for example, can easily take 1/2 hour to accomplish. Another 1/2 hour to an hour for a good cone layup, dust cap, & solder job, and 15 min. or so for the final tests.
The genuine kits are not cheap, even to the dealer...I paid cost and shelled out about $180 for two 2235 kits. Non employees pay 7.5% tax on the $90 parts (three years' ago jobber price) plus any nominal mark-up on these materials.
The crux of this long-winded diatribe is... when you pay $150-$170 or so for such a driver re-cone, it is a fair price and represents great value when you consider the materials cost, expertise & tooling required...plus you get the 90 day "as new" warranty coverage in case there IS a problem afterwards. An hour or so of "Sweat equity" made as a do - it - your - selfer is a great labor of love to be done, but the repair center is a business with overhead costs, and everyone has to eat and have shelter. Getting an authorized factory certification in the first place is a fairly pricey matter, with training time and a pretty huge investment in an initial minimum parts inventory purchase is required, and the needed fixturing and non-magnetic tools must be purchased from JBL, and they AIN'T cheap...trust me on THIS! You must buy a set of gap gauges & alignment fixtures for each size and/or series of JBL drivers, as part of the startup "qual".
All things considered, I would just about toss it up as to whether I would do my own recones or just pay another pro.
Anyhow, that's how it all looks from here. Good Luck, ya'all.

Rolf
05-13-2003, 01:45 PM
Originally posted by Doctor_Electron

I worked for a JBL pro service center, and would like to share with you what you get for your $$ on an authorized re-coning.
The genuine kits are not cheap, even to the dealer...I paid cost and shelled out about $180 for two 2235 kits. Non employees pay 7.5% tax on the $90 parts (three years' ago jobber price) plus any nominal mark-up on these materials.
The crux of this long-winded diatribe is... when you pay $150-$170 or so for such a driver re-cone, it is a fair price and represents great value when you consider the materials cost, expertise & tooling required...plus you get the 90 day "as new" warranty coverage in case there IS a problem afterwards.
Anyhow, that's how it all looks from here. Good Luck, ya'all.

Hey!

Nice! The job here in Norway cost about US$ 300 each. It's worth it!!!

Rolf

Earl K
05-13-2003, 02:48 PM
Hi Locanti


Originally posted by locanti

I suppose it's easy in US to find replacement kit for JBL Le10 drivers but in Europe it seems that only the professional series speakers kit are available.

Well , I'm in Canada and the situation here is somewhat similar to what you experience, lots of JBL Pro service, but HiFi service is quite limited . Giskard ( briefly ) pointed out that this cone-kit is still made ( once in a while ) and is available but is now back-ordered. I believe that means that when JBL reaches a " threshhold " number of orders, then & only then will they make up a batch & then ship them out . I have no idea how long an "ordinary wait" might be . I had an order in for a pair of le10 cone kits last fall ( Nov.). Waited about 2 months before cancelling my order. The production run hadn't started yet so I didn't pay any financial penalties . Now it seems, that the run was never executed ( from this vantage-point ) .



Where can I found kits on the Web?Do you know some shop that sell overseas?:confused:
As far as I know you can't buy authorized JBL kits from any web-site. I've never looked, I don't recone and really don't want to have to . Consider dropping Giskard a private email and ask him what is possible and do-able for a situation like yours .

regards <> Earl K

obsessed?
07-12-2006, 10:33 AM
My first posting:I've been a speaker hobbyist and JBL 'le' owner for thirty five years. That said, I don't know much, really. I don't know exactly where this posting will end up, but I wanted to share a material/method for repairing surrounds that I discovered on my own, I'm probably not the first, but I haven't heard of this particular product being used on speakers before.
A flowable silicone, NOT the pasty window and door stuff, is available through auto parts stores. Sold as a windshield and glass sealant, it's makers, Permatex, have told me that it is not available in quantities larger than the 1.5 oz tube (item no#81730).
This stuff can do amazing restorations, though not super pretty ones, for rotting foam surrounds. The material tends to flow and smooth itself out, so at least it is not lumpy when cured. As long as you can lightly touch the foam surround without it crumbling, with a steady and careful hand you can make that surround into a durable silicone speaker edge. A small artist's paint brush is the best tool I have found to spread the silicone evenly, with a light touch, around the surrond.
Lansaloy hardens and cracks rather than crumbling, so for these speakers this material will only bridge the fissures and hold the edge together.
The best use of his stuff is probably the repair of drivers that are not worth reconing or that you can't afford to recone until later. Please reply, especially if you have good results or other uses for this product. Good luck!
Also if anyone has good advice on getting my 40 something year old
LE8's (no 't') reconed (i'm interested in having the best high end sound I can) please respond. Thanks.

sdaniel
07-12-2006, 01:58 PM
Maybe, but I also sincerely want to know about break in. I am awaiting delivery of the LSR 63 series components needed to for my home theater, and want to know how I should break them in, and how JBL normaly conveys that info to the customer. I remember setting up my brand new 4410's and not being to happy - but the book or dealer never said anything about break in! I simply tweaked the tone controls, had a beer and cranked them up, which worked, but may not have been the best approach.




Thanks,
Sdaniel

lsr 25 p x 2 rear
lsr 6328p x 1 center
lsr 6332 x 2 front
lsr 6312sp x 2 subs

JonathanKeehn
07-19-2006, 01:43 PM
I have a pair of LE 15's reconed with 2231 cones for better power handling capacity. After 10 years the foam surrounds started splitting where the surround meets the cone edge causing a buzzing on hard bass notes. Rather than ship them off to JBL for a recone I decided to apply some common rubber cement along the split line about 1/8" either side and see what happened. The repair worked very well with no discernable difference to my ear except that the buzzing was cured. I regularly drive my L-300 style system to 300 watts per channel which is about double the woofer's capacity. To my ear the resonance frquency has changed very little and I will keep that $ 2.00 bottle of rubber cement handy if I need it. One woofer has a split from the 3 0'clock position to the 6 o'clock position which is a quater of the total surround circumfrence. I personnaly wonder if coating the entire surround would affect the Fs that much. If any of you have a similar situation this solution might be worth a try.

edgewound
07-19-2006, 01:48 PM
I have a pair of LE 15's reconed with 2231 cones for better power handling capacity. After 10 years the foam surrounds started splitting where the surround meets the cone edge causing a buzzing on hard bass notes. Rather than ship them off to JBL for a recone I decided to apply some commmon rubber cement along the split line about 1/8" either side and see what happened. The repair worked very well with no discernable difference to my ear except that the buzzing was cured. I regularly drive my L-300 style system to 300 watts per channel which is about double the woofer's capacity. To my ear the resonance frquency has changed very little and I will keep that $ 2.00 bottle of rubber cement handy if I need it. One woofer has a split from the 3 0'clock position to the 6 o'clock position which is a quater of the total surround circumfrence. I personnaly wonder if coating the entire surround would affect the Fs that much. If any of you have a similar situation this solution might be worth a try.

Whoever decided to recone your LE15's with a 2231 kit obviously didn't pay attention at recone training or read the manual. Those two cone assemblies are not interchangeable...never have...never will be.

But some people don't believe the factory. Drives me crazy.:banghead:

These are the kinds of posted info that drove Giskard to the edge.

JonathanKeehn
07-19-2006, 01:54 PM
Even with non-recommended cones my system sounds fantastic. When these drivers finally go, I will simply replace them with 2235 H's or with the 1500 AL - God forbid if JBL ever sells them in the US.

edgewound
07-19-2006, 02:29 PM
Even with non-recommended cones my system sounds fantastic. When these drivers finally go, I will simply replace them with 2235 H's or with the 1500 AL - God forbid if JBL ever sells them in the US.

It's great that they work for you. I just think the Lansing Heritage should be kept pure by not incestuously interminging parts within the immediate family.

Geez....cousins far enough removed can marry...but brothers and sisters should never hook-up...as the Creator intended.

Jus' tryin' to keep it real....which is a struggle with non-believers.

JonathanKeehn
07-19-2006, 04:12 PM
Purity is fine and admirable but my ears are the final arbiter. The LE 15 doesn't have the power capacity to suit my listening level tastes. Back in the late 60's when I bought a pair of Soveriegn I S8R's I kept destroying the LE 15 Woofers with the JBL energizer which only put out 40 or 60 watts per channel. Fortunately, JBL kept repairing them under warranty. I always appreciated the Alnico bass kick (although some would dispute its existence). I'll trade higher SPL levels for some linearity loss any day. Just my personal taste.

edgewound
07-19-2006, 05:02 PM
Purity is fine and admirable but my ears are the final arbiter. The LE 15 doesn't have the power capacity to suit my listening level tastes. Back in the late 60's when I bought a pair of Soveriegn I S8R's I kept destroying the LE 15 Woofers with the JBL energizer which only put out 40 or 60 watts per channel. Fortunately, JBL kept repairing them under warranty. I always appreciated the Alnico bass kick (although some would dispute its existence). I'll trade higher SPL levels for some linearity loss any day. Just my personal taste.

I won't argue with you....you're right.:banghead:

JonathanKeehn
07-24-2006, 08:25 PM
Dear Edgewound:

I made an error in my previous posts. My LE15's were reconed with 2215 cones, not the 2231's. I just looked at the 10-yr old boxes and realized my mistake. :banghead:

edgewound
07-25-2006, 11:30 AM
Dear Edgewound:

I made an error in my previous posts. My LE15's were reconed with 2215 cones, not the 2231's. I just looked at the 10-yr old boxes and realized my mistake. :banghead:

Hi Jonathan....

Thanks for going to the trouble to correct your post...that was good of you. My faith is restored in the reconer who fixed your LE15's right:) .


Could be you kept frying your originals with underpowered amp clipping that has relativley recently been discovered to be the culprit of burned voice coils....rather than too much power....although that can happen too;) .

Have a great day.

Mr. Widget
07-25-2006, 11:42 AM
Could be you kept frying your originals with underpowered amp clipping that has relativley recently been discovered to be the culprit of burned voice coils....rather than too much power....although that can happen too;) .I don't know about relatively recently... unless the '70s is considered relatively recently...:D but yeah, I have blasted the shit out of LE15As with hundreds of watts for hours at a time and never damaged them... I was in a different room to protect my hearing of course.;)


Widget

edgewound
07-25-2006, 11:59 AM
I don't know about relatively recently... unless the '70s is considered relatively recently...:D but yeah, I have blasted the shit out of LE15As with hundreds of watts for hours at a time and never damaged them... I was in a different room to protect my hearing of course.;)


Widget

Since I'm in the speaker repair business, this little tidbit of info is almost a daily discovery for some users....especially DJ's that just bought a complete "matched" system from some big box music store....that is motivated to move the "big boxes" out the door whether they are "matched" or not. The systems end up costing the user double due to repair bills by not having enough system to do the job right....let alone well.

User education and restraint is the key to reliability in this arena...but both are lacking terribly.

It's not rocket science to keep the red clip lights from flashing on the VU's.....of course when you're ripped out of your mind...most things do become rocket science:p :D

Mr. Widget
07-25-2006, 12:04 PM
I think along with education there must be an experience factor too... back in the 70's I blew up pretty much one of everything I ever owned... I haven't had to repair or replace anything since... well, except for a wall of speakers one infamous Halloween party but that was a very extreme case in oh so many ways...


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JonathanKeehn
07-25-2006, 07:08 PM
I would agree with Edgewound that clipping in the JBL 40 W/Channel Energizer could have been the reason I lost 2 LE 15's. I traded in the Energizer and SG 520 Graphic controller for the 60 W / channel JBL SA 600 and never had any more problems with the S8 R's. I can also appreciate why JBL dumped the foam surrounds for accordion rolls - durability.

Mr. Widget
07-25-2006, 09:38 PM
I can also appreciate why JBL dumped the foam surrounds for accordion rolls - durability.What? :blink:

That never happened. They did change from the Lans-a-loy foam that stiffened with time to urethane foam that simply falls apart... but woofers used for deep bass where low distortion is required all use foam or rubber surrounds... no one uses cloth for a deep bass woofer.


Widget

JonathanKeehn
07-26-2006, 01:22 PM
Mr. Widget: I was referring to the bass drivers JBL actually sells as components to the public i.e 2226 and the like. We Americans are too unworthy to be able to actually purchase their top echelon units. It's hard enough to get an occcasional 2235 when they go into very small production runs to satisfy the West Coast sound pros. I'm grateful that JBL still provides replacment cone kits to their service agencies so we can still enjoy 40-yr old technology through the used market. I wonder when Harmon will turn the water off on those too. As you can surmise, I'm not a fan of large corporations.

Ian Mackenzie
07-27-2006, 07:23 AM
I don't know about relatively recently... unless the '70s is considered relatively recently...:D but yeah, I have blasted the shit out of LE15As with hundreds of watts for hours at a time and never damaged them... I was in a different room to protect my hearing of course.;)


Widget

That must have been when you were a teenager.

But I don't understand why if the room was empty.

But then you upgraded to 1500 subs more recently.:D