Re-charging Alnico Magnets

[InventiveAudio.com]

It seems that the concensus is that Alnico magents don't lose magnetism due to age but can degrade due to over powering or abuse. I guess the guy at the speaker shop wanted to recoup some of his investment in the machine that does this.

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My Klipsch Page

www.nyonline.com/klipsch

[Malcolm]

Well, the machines are fairly expensive!

[kenratboy]

Ohh, ummm, of course its, ummm, broken!!! HONEST!

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Receiver: Sony STR-DE675

CD player: Sony CDP-CX300

Turntable: Technics SL-J3 with Audio-Technica TR485U

Speakers: JBL HLS-610

Subwoofer: JBL 4648A-8

Sub amp: Parts Express 180 watt

Center/surrounds: Teac 3-way bookshelfs

Yes, it sucks, but better to come. KLIPSCH soon! My computer is better than my stereo!

For JBL related subjects and more fun, click: http://www.audioheritage.org

[John Warren]

kids don't play with magnets anymore, they just play video games.

[InventiveAudio.com]

John,

Not true my daughter has a huge horseshoe magnet. I get nervous each time she gets close to our TV. I once threw off the color of our TV by putting my sub driver near the set.

This message has been edited by trader on 08-06-2002 at 03:01 PM

[colterphoto1]

bump

[Daddy Dee]

good bump Colter.

It is my understanding that the EV factory in Russellville Arkansas will remagnitize Alinco magnets. Bob Crites could offer more advice for contacting EV.

[IB Slammin]

Do the speakers work? Do they sound great? Then leave em alone for Crissakes!!...and just LISTEN TO EM!!!

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I can now receive private messages

Andy,

Hey you old coot! You doing OK over there? Good to hear from you!

Terry

[djk]

"Hey you old coot! "

You're responding to a five year old thread.

[Tonetwisters]

On 8/2/2002 at 3:35 PM, Malcolm said:

Do your 1965 K-horns work? If so, the bit about 10% loss per year is pure B.S. By now, the magnetic field would be down to about 2% of what it started out as if it were true. Your speakers would be pretty useless.

How close are the magnets to their original strength? Hard to tell without a gauss meter and the figures from the manufacturer. Probably pretty close.

Magnets can be partially demagnetized if the speakers are abused. Alnico magnets are more susceptible than ceramic magnets. The magnetic field produced by the voice coil essentially tries to demagnetize the magnet. Normally, when the voice coil's field is reduced or removed, the magnet recovers. If the voice coil's field is too strong, the magnet is not able to recover and permanently loses some of its magnetic field. If you don't abuse your speakers, you should not have a problem. If you fry voice coils, you may have one.

If I had speakers in for a recone, I would expect to have the magnets discharged before the gap was cleaned and recharged after. This is the only way to get out any magnetic particles, if there are any, in the gap. Short of a recone, I would not bother recharging the magnets.

I am a guitarist of 58+ years, and I am just entering into the magnet thing. I have been around JBL guitar speakers for most of my playing time, but have known little about them. However, I am beginning to believe that (dependent upon what genre of music you play) weakend magnets tend to sound sweeter and less harsh for vintage preferences, than do charged up magnets, which are probably great for contemporary styles of music. By the way... At one period in my life (early '80s), I sold Klipsch stereo speakers and came to believe that the Klipsch brand of raw speakers were the only speakers I have ever seen/heard that were in the same class as the JBL's. Or better. VERY efficient.