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dougzilla
01-21-2004, 02:03 PM
I have a pair of LE14a's in my Lancer 99's. The Lansaloy surrounds have become quite stiff--they are original from 1969--and I had to repair a slight tear a few years ago. I haven't got the measurement equipment to test for loss of low frequency response, but I can certainly see that the "throw" is way down on sub-audio signals (LP/turntable "rumble") compared to what I remember. I have become reluctant to play the system at more than moderate volume for fear of more tears.

What can I do / should I consider for replacing the surrounds?

Also, any issues to be looking for elsewhere in the driver/crossover complement? This is a ported two-way system with LE20 tweeters and the SE-408S built-in amplifier (currently out for repair). One of the LE20's has a dent in the dome but it doesn't cause audible distortion (to me anyways).

Thanks,

Mr. Widget
01-21-2004, 02:17 PM
Yes old Lans-aloy does get very stiff over time. The absolute best fix is a complete recone, the next best fix is to replace the surrounds, but my suggestion is to try brake fluid first.

Do a search on this forum under "Brake Fluid" and you will find several threads dealing with this topic.

Widget

boputnam
01-21-2004, 06:51 PM
Hey, Doug...

If you're interested in going the re-surround, route, here's a thread where some sources and methods are discussed: Resurround step-by-step - Link (http://audioheritage.csdco.com/vbulletin/showthread.php?s=&threadid=469&highlight=stepbystep)

Most agree, if you've access to JBL factory repair, a recone is preferred, because that spider is likely a bit tired, too. However, a resurround is often a great solution. And you will immediately notice the LF you've been missing... :yes:

GordonW
01-21-2004, 09:39 PM
Well, IME, fortunately... most of the time, when the Lansalloy surrounds get stiff, they prevent massive cone motion and thus "protect" the spider pretty well. I don't usually see many old JBL woofers such as these LE14A's, that the spiders aren't nearly PERFECT. Usually, unless the surround has been allowed to crack off and the cone starts wobbling, you should be able to do a foam-surround retro-fit, and be in top-notch shape.

Regards,
Gordon.

dougzilla
01-21-2004, 10:17 PM
Bo and Widget,
Thanx for the threads. Looks like I can go in stages of risk and expense.
1. Try to restore some surround flexibility with DOT-3 brake fluid. Pray I don't get it on the cone itself, nor apply too much, nor get it uneven, nor dissolve any glue, nor leave it on too long lest it all turn to goo, BUT...
2. Even if I screw it up, never fear, just replace the old surrounds with a new foam surround kit. Excellent illustrated instructions from cone-master black belt Bo. [I do assume I can get foam kits for the 14" units, rather rare?] Jus' be careful with the scalpel and doncha be gettin gloo all over everythin', ya' know. I am actually fairly experienced with the blade side of life, being an amatuer neurosurgeon, but even if I botch the foam job, there is still...
3. Send the whole mess to a Pro for a full re-cone. New spider as well. Destroys some collector value, but what the heck, I'm keeping these until its my kid's problem. At least she's a better musician than I am.

So, if I bump my way down to the bottom,
- Will JBL do factory re-cones on LE14a's? If so, how much moola?
- Is there a factory authorized facility in N. CA?
- Will I really miss those big white cones? (Even though they're behind the grill, I know they're there. Sort of like, well, you know, think of that old Madonna video, only in reverse....)

p.s. Still have one pair of whitey's in my 4311's, which are my near field studio monitors of choice, to this day.

Best,

boputnam
01-22-2004, 08:42 AM
Hey, Doug...

Some great advice from Gordon.

I know that JBL Dog just got some LE14A's reconed, and they turned out beauty - white cone and all :yes: . I don't know whether there is any good recone facility in NorCal (I think Widget does know one...), but many here recommend Orange Country Speaker - Link (http://www.speakerrepair.com/)

Just what is an "amateur neurosurgeon", anyway... :rotfl:

Don C
01-22-2004, 08:51 AM
Here is a place in the north bay that can probably do them.
http://www.abrown.com/

dougzilla
01-25-2004, 10:24 PM
Just what is an "amateur neurosurgeon", anyway...

So many cats, so little time....

No, really, I am an experienced builder of stringed instruments and an out-of-date electronics repairman, so I think I qualify. I hot wired a few early Apple computers to up the clock speed, and I built some non-standard electric guitars back in the 70's. Fun times....

Back on topic, I've written to A Broun Soun to ask about refoam and recone prices Thanks all for the advice and I'll keep ya posted.

Best,

JBL Dog
02-01-2004, 10:00 PM
Doug:

Giskard informed us a while back that JBL has discontinued LE14A kits (along with many others). However, I'm sure there's still a bunch of 'em stocked in authorized service centers.

So, if you or anyone else need a new kit, you may want to try to track one down. My local JBL service man (Lloyd at Spectrum Sound in St. Louis) has one in stock.

Good Luck!!

This message comes from JBL Dog :band:

dougzilla
02-23-2004, 09:37 PM
I'm glad to report that I replaced the LE14a surrounds and the results are spectacular. Details:

I used the foam kit from Orange County Speakers (gotta support California in its time of fiscal woe). It arrived promptly and fit perfectly. Decided against using brake fluid on the lansaloy, as close inspection revealed numerous microcracks that I figured would lead to tears sooner or later.

I had some trouble removing the old stuff from the speaker cone. It mounts from the front and I didn't want to risk a tear, so was reluctant to scrape. The second one went much better. I made a radial incision down through it to the face of the cone and peeled it off in one continuous strip. My secret weapon? 3M General Purpose Adhesive Cleaner, a blend of several petroleum based solvents. It softened the old glue just enough to get it to release from the cone, staying with the lansaloy.

I painted solvent around the whole circumference with a small brush and let it soak in a few minutes before starting. I worked the edge of a straight exacto blade under one end and went around gradually using the blade at the release seam and extra dabs of solvent on the really sticky points. Some white cone coating came off but not too much. No long lasting stains on the cones, either.

For the rest of the glue, on the frame and the gasket, acetone was, by far, the best and fastest solvent. Be sure you use it in a well ventilated area--I really mean outside--or the fumes will do you in. And be careful where it goes, because it takes paint off just as fast!

Results far exceeded my expectations. Not only are the lows deeper and fuller, but the whole range up to crossover is smoother and the voicing is more distinct. I guess the sound went away so gradually I never really noticed, but now all is revealed anew!

One little problem, tho. Now that I can crank 'em again, one of the tweeters will squawk briefly on certain high notes. I'll start another thread, picking up on one of the other ones I've read on LE20-1 repair.

Thanks again for all the advice!

Doug