JBL D130 Magnet Cover Removal

[Big-D]

Hi. I'm new to this forum. Not sure if this has been discussed elsewhere, but is there a proper method for removing the magnet cover from the plate on a JBL D130? It is off center and needs to be recentered. I've worked on many other brands, but this is the first D series I've come across with this problem. Thanks for any help you can offer.

Ed

[NickH]

Hi D,

Its a pretty easy task. But its not possible with a cone in the frame. The screws that hold it to the frame are under the spider. You have to remove it. Then take all the screws out. This removes the whole magnet assemble. The technically isn't a cover on the mag. The outside cover on the. At is actually of the magnetic circuit. Once off you can remove the top plate. But its tricky and it will need to be recharged once removed.

I'd send it to a good speaker shop. It will save you from many headaches.

Hope this helped some.

Nick

[Big-D]

Hi Nick,
Thanks for the reply. I always like to ask before I do something I've never done before.

The reason I wanted to remove the magnet assembly was that it sat slightly crooked on the main plate. The voice coil gap was just fine. I was curious to find out if somebody had monkeyed with it, or if this was a factory flaw. The speaker is stripped down and ready to be re-coned so the screws were accessible. I removed the basket and the outer plate from the magnet assembly and found it is pinned in a permanent position and can only be mounted one way. It appears this is a factory issue, so I'll just put it back together and will go ahead and recone it.

With that said, I can see very little reason for anyone ever needing to remove this assembly, there's not much you can do there, but if anyone wishes to proceed (and you value your extremities) be very cautious when removing the outer plate.......... That is one powerful magnet!! .....and it wants to eat you........alive!!!

Thanks again
Ed

[NickH]

Yep the top plate is pinned. So by what your saying the screw holes aren't concentric with the outer diameter?

I'm afraid your stuck on this one without a bunch of machine shop work.

Good luck.

[hjames]

Hi. I'm new to this forum. Not sure if this has been discussed elsewhere, but is there a proper method for removing the magnet cover from the plate on a JBL D130? It is off center and needs to be recentered. I've worked on many other brands, but this is the first D series I've come across with this problem. Thanks for any help you can offer.

Ed

If its an ALnico speaker I believe the answer is to demag it,
take it apart, align everything correctly, glue well, then remag it.

as the legend goes, no user serviceable parts inside ...

[4343]

Hi Nick,
Thanks for the reply. I always like to ask before I do something I've never done before.

The reason I wanted to remove the magnet assembly was that it sat slightly crooked on the main plate. The voice coil gap was just fine. I was curious to find out if somebody had monkeyed with it, or if this was a factory flaw. The speaker is stripped down and ready to be re-coned so the screws were accessible. I removed the basket and the outer plate from the magnet assembly and found it is pinned in a permanent position and can only be mounted one way. It appears this is a factory issue, so I'll just put it back together and will go ahead and recone it.

With that said, I can see very little reason for anyone ever needing to remove this assembly, there's not much you can do there, but if anyone wishes to proceed (and you value your extremities) be very cautious when removing the outer plate.......... That is one powerful magnet!! .....and it wants to eat you........alive!!!

Thanks again
Ed

The act of separating the magnetic circuit is enough to reduce the magnetic force considerably, IIRC, it will need to be re-magnetized after that.

[NickH]

If its an ALnico speaker I believe the answer is to demag it,
take it apart, align everything correctly, glue well, then remag it.

as the legend goes, no user serviceable parts inside ...

Nope. There quite easily separate. A putty knife, hammer, and a screw driver. You the knife to separate the top plate from the pot by tapping it between then.Tap it in and work it around. Use the screwdriver just to hold the gap open. Once you've got it off the pins you can pull the plate off. But yes as I mentioned in my previous post, it will need to be remag'ed.