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Thread: LE15 repair/restoration

  1. #16
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    Quote Originally Posted by Earl K View Post
    All that seems like a good plan ( but why not recone the empty basket first before doing anything else just to see just how close to the recone sounds to an actual le15a ).
    I am in no rush to sell anything, I will make sure I am certain with my final choice before that happens. I still need to refinish the cabs and sort out the crossovers, getting that tar stuff off is going to be a fun job. Once I've finished those jobs then I can start testing different woofer configurations, and hopefully one day get them remagged too.

    Quote Originally Posted by Earl K View Post
    Cone Removal ( complete ):

    Are you allowed to purchase ( by EU/UK rules ) MEK ( Methyl Ethyl Ketone ).

    It's commonly used by reconers to loosen up hardened/aged glue.

    It's highly volatile ( brain damaging even ) and must be used in a well ventilated area ( outdoors with a slight breeze is best ).

    I believe the next best might be Acetone.

    Yes I can find MEK here, am I best using it to loosen the glue on the surround and spider? What is the best technique for doing that?

  2. #17
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    Quote Originally Posted by budney View Post
    I am in no rush to sell anything, I will make sure I am certain with my final choice before that happens. I still need to refinish the cabs and sort out the crossovers, getting that tar stuff off is going to be a fun job. Once I've finished those jobs then I can start testing different woofer configurations, and hopefully one day get them remagged too.



    Yes I can find MEK here, am I best using it to loosen the glue on the surround and spider? What is the best technique for doing that?
    Yes, the spider & surround both need to be released from their glue points.

    I imagine ( since I've never lifted a complete cone out ) that a putty knife, Q-tips for targeted application of the solvent is the way to go ( start with the surround since it's furthest away from the other parts of the assembly where you don't want the MEK to loosen the glue bonds ).

    You'll need to first remove the cork/foam gasket covering the glued edge of the surround.
    - I believe there are some YouTube videos that show the best way to accomplish this task while saving the gasket.


  3. #18
    Member ompdiburi's Avatar
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    I suggest you to check the dc resistance at voice coil exit before proceeding, the repair is not difficult, it could be easly done if you have little manual skills, sure is much easyier than removing the cone assembly, probably there are some tutorial videos online about the wires substitution.
    Good luck!

  4. #19
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    I finally got round to getting these monitors up and running. Took a while to refinish the cabs and repair the crossovers.

    I got the aftermarket cone kit in the frame. I didn't have an original coil to compare it to, so couldn't comment on how close it was to the original. But getting it in the monitors, I really cannot tell the difference. It sounds the exact same to me as the original cone. It looks slightly different, the paper pulp is slightly darker than the original. When you read SoundSpeakerRepairs website, especially on their D130, E and K series kits, you can see how hard they worked hard to get as close to OEM specs as possible, so I have confidence that their other cone kits are to the same standard. It shows, as it is indistinguishable from the original.

    Initially when listening to them, it felt like the 2441 on the 2311 horn was overpowering the LE15, even with the crossover on the lowest setting. It felt like it was very much stuck in the 70s, I was a bit disappointed, hardly any low end. I was thinking about maybe getting an L pad to lower the 2441 even more. But I stuck some White EQs on them, got my iPhone FFT app and got it pretty flat. They sound incredible! The low end was back, the classic JBL punch that I know and love had appeared again. I had a friend who's a brilliant engineer and has a fantastic ear listen to them, he said they were a very comfortable sound and he would have no problem working with them.

    For the 2405, they came with some cheap Chinese diaphragms installed, but also came with the original blue diaphragms. The Chinese ones were terrible, straight away I swapped them out. One original blue diaphragm had quite a few dents in it, not sure how that would affect the sound, but it sounds good to me. Even though I'm sure they're quite old now, I'm happy with them. Testing the 2441, and they were a bit odd. One was distorting around 500hz, and the other one was crackling with loud volumes. I think its probably a combination of the gap needing cleaning, and the foam rotting. I forgot to swap the foam out before installing but I will order some felt and service the 2441.

    Next step I think would be to recone the LE15B driver I have, and try to extract the cone assembly fully so then I can sell to the Asian market. I'm concerned that the valuable original driver will get overworked as this will be a working studio so will get a lot of use...and it also looks a little bit odd so may as well make them match. I think I need to widen them slightly as they are a bit too close together, but we will get to that eventually.

    You can see the EQ curve that I used to get it flat, I'm very happy with the result. Whats strange with these EQs is that theres a peak on the low cut, so theres actually more low end if I cut it at 40 or 50 rather than leave it flat. Also I forgot with horns this efficient, the noise floor is amplified. Sounds like I will need to recap the amp (BGW 250A) too!


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  5. #20
    Administrator Mr. Widget's Avatar
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    Looks like you have made great progress! Having gone down a similar path many years ago, I would recommend adding the L-pads. I actually built custom crossovers which I thought sounded much better than the originals, but at a minimum I’d add the L-pads so you can use your White EQs for fine tuning instead of major corrections.


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  6. #21
    Senior Member Flodstroem's Avatar
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    Quote Originally Posted by budney View Post
    Only on the LE15A. I currently only have 1 working driver, and that’s around 9 ohms. I had thought about repairing the LE15B but it’s not worth it
    take a look at this post:
    http://www.audioheritage.org/vbullet...JBL&highlight=
    Flodstroem

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