Speaker repair disaster

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Hi

I am a bassist and have recently bought a secondhand tech 21 landmark bass amp, I noticed that there was constant distortion and on closer inspection I narrowed the sound down to coming from the speaker's dust cap. So probably rather stupidly I jumped straight into removing the dust cap with a scalpel and after finally getting the thing off, the speaker makes no sound at all. I am afraid I have cut cleanly through the cone it's self and cut the connection to the cone. Is there anything that can be done to salvage this mess? I'll go take some photo's so people can get a better look at what I have done...

Thankyou!
 
Hi,

I can't see the break that needs resoldering. Fix that first.
A small piece or 2 pieces of wire may help. * Make sure
everything on the cone is glued down after soldering.

To start rub wood glue along the line of damage on the back.
As the pulp softens push the line of damage back flat, don't try
to especially fix the cuts all the way through in one go. Let that dry.
2nd time round from the back redo the areas with a cut. Let that dry.

Clean up the front of the cone and the dust cap. Wood glue around
the dustcap and let it dry. Repeat the rear procedure on the front.
Finally wood glue around the dust cap and reattach it.

FWIW for anyone reading this rattling dust caps are best fixed by
running a line of glue around them, not trying to remove them.

rgds, sreten.

* You might need to scrape off some insulating laquer to get
a good joint to the voice coil wire, depends where it is cut.
 
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Ok so I managed to glue the speaker back together and solder the split wires but the speaker is still distorting like before.. Think maybe I was too hasty in presuming it was the dust cap I think all I was doing was dampening the speaker when I put my hand on it rather that fixing the distortion.. I've run the head of the amp through other speakers and it sounds like a completely different amp, the damaged speaker goes real loud but the crossover between clean and distortion seems completely invisible so even at low volumes it's distorted. I've done a few tests I know on the speaker ie pushing the cone in and out and it sounds clean, no scratchy sounds and I've checked for any tears in the cone (and fixed the ones I caused) are there any other tests I can do to know that it is blown? I don't want to buy a new speaker unless I really have to and it seems strange that there is no visible damage, big bass speakers like this should be able to take quite a pounding..

Thankyou!
 
Is there any indication what brand/model speaker is in your amp? It could probably be re-coned for less cost than buying a completely new speaker.

Also, since this is a bass amp, is the cabinet ported (with a hole or vent in the baffle)? If so, the speaker in there has been tuned to the size of the cabinet and the dimensions of the port. If that's the case, and if you decide to replace the speaker, you'll want to get the same make/model of speaker that was originally in it, so that the bass response is what you expect.

This is another point in favor of having the speaker professionally re-coned. A good shop should be able to use a close enough voice coil-cone-suspension so that the end result works well enough in the cabinet with its vent.

If the cabinet is sealed, then you won't have to be that careful with matching the speaker driver to the cab and its vent.

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