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QwertyAccess
04-04-2006, 02:34 PM
I have a question about magnet recharging, sorry if im asking a dumb question i'm curious :P, i tryed searching on the forums but didnt see anything, what exactly does it do? How do you know when you need to recharge it? (i assume you test by putting a peice of metal near the magnet and see if it pulls it or not, i could be wrong..) Does it do any good to recharge a magnet when its already working fine? Thanks :)

duaneage
04-04-2006, 06:35 PM
The ALnico magnets apparently lose their strength when subjected to very high power over time. THe parameters of the speaker change and the output is reduced. The magnets can also be discharged from an impact from what I've been told.

Specialty repair shops can recharge the magnets, I understand it is not expensive to do so.

edgewound
04-04-2006, 06:53 PM
I have a question about magnet recharging, sorry if im asking a dumb question i'm curious :P, i tryed searching on the forums but didnt see anything, what exactly does it do? How do you know when you need to recharge it? (i assume you test by putting a peice of metal near the magnet and see if it pulls it or not, i could be wrong..) Does it do any good to recharge a magnet when its already working fine? Thanks :)

The magnetic gap strength can be checked with a Gauss meter.

The cost of a recharge is about $25ea. No need to recharge ceramic magnets, but alnicos should be checked for flux density and then recharged if needed.

QwertyAccess
04-04-2006, 07:19 PM
hmm i would imagine the 2214H Driver has an alcino magnet, given its age?

Ken Pachkowsky
04-04-2006, 07:25 PM
Orange County Speaker Repair will charge a pair of 375's or 2441's for 40.00.

Takes a few hours.

Ken

Steve Gonzales
04-04-2006, 08:04 PM
hmm i would imagine the 2214H Driver has an alcino magnet, given its age? No need to recharge that model, it is ferrite

QwertyAccess
04-04-2006, 08:20 PM
Ah thanks, thats a bit nice to know, the LE-10 is an older woofer, i imagine those then would use alcino? out of curiousity

Steve Gonzales
04-04-2006, 09:20 PM
If the model is LE10"A", then it is Alnico. Usually you can identify an Alnico driver by sight. The magnetic structure is different. Look at the 2214's magnet and look at the LE10a's (if they are indeed a's). Most of the Alnico models have a covered magnetic return pot covering the magnet. It is usually painted with wrinkle paint. Alot of the home audio versions have and "A" after the number, but that is not always the case. There is a wonderful source of information here on the site. Click on the square that says "Lansing Heritage" in the upper left of your screen, and then click on the library option in the menu on the left, select JBL from the top row of options, then specs. You will find a wealth of information about different drivers, both pro and home. Read through the literature and enjoy. Hope this helps and happy hunting, Steve G

John
04-04-2006, 09:38 PM
I have seen the recharging performed at Great plains audio on my 2441's and the actual charging takes seconds to perform, When you ship a pair of drivers to be recharged what you are really being charged for is the time it takes to unpack and repack the drivers and perhaps 10 minutes for fitting the drivers into the charging device. I also had my pair of 2440,s de-magnetized and it took a few minutes longer.:D

scott fitlin
04-04-2006, 09:42 PM
Hi John, I would like to know what, if any, difference you heard after your 2441,s were recharged?

:)

John
04-04-2006, 11:40 PM
Hi Scott The 2441's were bought off of ebay, and the seller claimed they were used for sound reinforcement by a rock band.:band:

They had 2445 ti's in them when I got them. I assumed they could use a recharge after being used hard? I listened to them for maybe a hour in a 2 way system just to confirm they were ok, I also did a impedence test with a meter. After they were charged I swear when I did a impedence test once again, the sound you hear when you touch the test lead to the driver terminal was brighter as well as louder than before???:hmm:

I will be putting brand new 2441 dia in them when I put them in service in my long overdue project system!!! :bouncy:

I will try to remember to bring a camera next time I am getting some recharging work done at G.P.A. and post some pictures.:)

QwertyAccess
04-05-2006, 12:28 AM
Hmm thats interesting to know how you can lose magnetic power, curious does anyone know where there might be a 2214H spec sheet? i couldnt find one on the website, i only saw 2215 and thats totally different, 15 incher.

Magnet3
04-07-2006, 09:56 AM
I have a question about magnet recharging,

That's kind of a personal question.....maybe you should ask Edgewound ;)

sorry if im asking a dumb question i'm curious :P, i tryed searching on the forums but didnt see anything, what exactly does it do?

Again, I suggest you ask Edgewound :p

How do you know when you need to recharge it?

When I get grouchy, :rotfl:


Does it do any good to recharge a magnet when its already working fine?

Oh yeah.....it does alot of good, believe me! A good recharge improves performance tremendously! :)

Thanks :)

No problem....:D