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View Full Version : 4312 malfunctioning tweters.



Killiansredleo
02-03-2008, 12:13 PM
I just purchased a pair of 4312 off eBay. The ad stated that the tweeters were not working. They appear to have a round tweeter (have not received them yet). I am wondering if perhaps the crossovers are damaged since they state that both tweeters are not working.

If it is the crossover what is the most likely problem and if it is only the tweeter which model should it be replaced with?

I am new to the Lansing forums so I will try to include the best picture I have of the speakers, perhaps someone can identify the tweeter just from the pictures.

http://i9.ebayimg.com/05/i/000/d5/f2/d3c6_1.JPG

Thank you for any help available.

Fred Sanford
02-03-2008, 12:33 PM
People often damage the fragile wire leads to those tweets when changing out the foam surrounds, possible they were fine until somebody attempted to "fix" the foam. Sometimes that's repairable, not always. Tweets are available here sometimes, and on E-Bay pretty often.

Paperwork here says they should be LE25-2s, others more experienced folks should be coming along any time now:

http://www.lansingheritage.org/html/jbl/specs/pro-speakers/1983-4312.htm

je

Mannermusic
02-05-2008, 02:09 PM
Just went through that - seems LE25-2 tweeters are biting the dust in droves! Both were failed on my recently purchased 4312 monitors. Sure-fire answer to your problem, pull 'em out and check the resistance across the terminals. Spec is 3.5 - 3.8 ohms. Be careful removing, they tend to stick to the baffle - may have to give 'em a whack with a plastic hammer from the back. Easy does it. Don't recommend trying to pry from the front, the baffle material is low grade (soft) fiber board, easy to gouge. Mike Manner:)

PS: The LE25-2 can be re-coned - I just checked with my local JBL pro shop, kits are available for approx. $77 (plus labor). That's what I plan to do.

Killiansredleo
02-08-2008, 02:16 PM
They are immaculate and you guys were right, the tweeters themselves are shot, completely open circuit. Dont know if I will have them re-don or just keep looking for a replacement set. If anyone has a set please contact me.

Mannermusic
02-08-2008, 07:06 PM
They are immaculate and you guys were right, the tweeters themselves are shot, completely open circuit. Dont know if I will have them re-don or just keep looking for a replacement set. If anyone has a set please contact me.

Same as mine. Frustrating. They're getting older every year and not as easy to find - never know for sure what you're getting. The re-cone is not exactly cheap but they're good as new when you're done. I'd say a good value if you are going to keep the speakers. Best wishes either way. Mike

duaneage
02-12-2008, 02:53 PM
If your going to keep them forever a recone (while still available) is not a bad idea. You'll have the knowledge they are new and should last for decades with proper care.

Once the recones are NLA the prices for old, tired tweeters will skyrocket. You'll end up paying through the nose for drivers with
dented domes,
faded cones,
and missing foams.

Hey, that is a great rhyme.

Killiansredleo
02-13-2008, 02:48 PM
Forever is a long time. However, as mike suggests, I am going to have the tweeters rebuilt. I have located another pair which I am going to use while I have the originals re-built.