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Author
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Topic: Peavy BW 1501 repair question
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Michael Brodie
Member From: Arcata, California, USA
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posted 30 November 2004 01:28 PM
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Hey,
I have an older flat-magnet 1501 from an older session 500 amp. It recently has begun buzzing terriably. Upon inspection, I noticed taht a dark foam plug has come unglued under the aluminium dust cap. I can see it moving around through the central screen on the back of the driver. What, if anything, can be done to repair this wonderful speaker? Before I noticed the foam, I ordered a 1501 from the local peavey dealer, and 6 months later it hasn't arrived... I'd rather repair this nice vintage speaker, as I loved the sound. Thanks for any suggestions or assistance.Brodie Thanks for any suggestions. |
Charlie Moore
Member From: Deville, Louisiana, USA
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posted 30 November 2004 01:59 PM
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Michel,you can remove speaker from cab. remove three 1/4"bolt's(could be allen or hex head)gentle separate basket from magnet,if the foam has not got TOO hot you can clean the coil gruve on the magnet with double sided tape,and cleah coil with soft solvent,SOMETIME it works,if not i got a used 1501DT basket for$45.00..cya..Charlie.......... |
Craig A Davidson
Member From: Wisconsin Rapids, Wisconsin USA
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posted 30 November 2004 02:21 PM
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There is also no guarantee that it will sound exactly the same as the old one. It'll be close though. |
Michael Brodie
Member From: Arcata, California, USA
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posted 01 December 2004 08:44 AM
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Thanks for the replies so far. I now have one more question... Do I need to replace the foam to prevent dust entering the magnet gap? Also, is acetone a gentle enough solvent to clean the voice coils with? Thanks again,
Brodie |
Michael Brodie
Member From: Arcata, California, USA
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posted 01 December 2004 09:14 AM
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So, I've gotten the speaker out safely, and the three hex head retaining bolts off out of the magnet structure. But the magnet is stuck to the basket with some supernatural force... Does anyone have any suggestions as to how to safely remove the magnet from the basket? |
Ken Fox
Member From: Ray City, GA USA
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posted 01 December 2004 09:48 AM
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The last one I did was like that. The foam had melted in the gap and caused it to stick. I was able to rotate the magnet and break it loose. Cleanup was quit a process. I cleaned the voice coil with Q-tips soaked in denatured alcohol. After that I used compressed air in the magnet gap. I then poured denatured alcohol in the gap, let it soak and then drained it out. I again cleaned with compressed air. After all that you can use brown tape (fold over a business card to stiffen) to clean the magnet gap. It is a slow, tedious process. After all that the speaker still might drag, as the heated voice may be out of round.A piece of felt glued in the screen area might be all the dust protection you need; I have tried it with success.
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Brad Sarno
Member From: St. Louis, MO USA
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posted 01 December 2004 05:20 PM
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I love those old flat magnet Black Widows with the spider web decal. They're the most JBL sounding BW's I've heard. They don't quite handle the power of the newer ones, but the tone is great and they're a lot lighter than the E series JBL's. I'd try everything to salvage it. Hopefully you can remove the cone ok. I found that the sticky, gooey melted foam is pretty tough stuff, but with some naptha, acetone, and alcohol, some skinny tools, elbow grease, compressed air, and patience that you can succesfully clean that gap and the voice coil entirely. Those old thinner paper cones are like gold and are WELL worth cleaning up and fixing. Brad Sarno |
Michael Brodie
Member From: Arcata, California, USA
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posted 01 December 2004 10:50 PM
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So, I got the speaker apart safely, and cleaned the molten foam gunk from both the coil and the magnet gap. But, it appears that the voice coil is out of round. You can hear it scratching as the cone moves in and out. What if anything, can i do to fix this now? I agree, I really love the sound of this. I would love to get it up and running. |
Wiz Feinberg
Moderator From: Flint, Michigan, USA
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posted 02 December 2004 08:16 AM
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Michael asked:
quote:
But, it appears that the voice coil is out of round. You can hear it scratching as the cone moves in and out. What if anything, can i do to fix this now?
I have had this problem in the past and tried this fix, with mixed success. Sometimes you can reshape the voice coil by inserting a cylindrical object the just barely fits, like a coffeecup, or drinking glass. Once you find a perfectly round object that fits, insert it and try to reshape the coil form back to the correct roundness.Wiz |
Ken Fox
Member From: Ray City, GA USA
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posted 02 December 2004 03:38 PM
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Sometimes it is one small particle in the gap. Get a good light and check it again![This message was edited by Ken Fox on 02 December 2004 at 03:38 PM.] |
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