What's going on here then? Death of Speaker

lamf68

Twin Reverb 40th Anniversary Edition, JBL K-120's in it...what the frigging hell has caused this? Is this a knock or is there something fishy going on inside the gubbins of this beast to cause such a horror show? I know the speakers were aftermarket upgrades and were old anyway, do amps do this to speakers and if so is there anyway I can fiddle around with a multimeter to see if something is awry...Cheers for any help here, just bought a new pair of Jensen Whatever they're called to fit in it but dont wanna switch it on for fear of this happening again.

ICBM

Looks like the dust cap has been pushed in and then maybe damaged in an attempt to get it out again. Nothing the amp could have done to have caused it.

It's well worth getting the damaged cap replaced, if the speaker doesn't need a complete re-cone - which it won't if it works and doesn't make nasty noises - these are valuable and sought-after speakers. Just make sure nothing gets into the space behind the cap and falls down into the coil gap - that *could* wreck the speaker.

lamf68

Top man, really appreciate the reply, absolutely delighted.

Edit:---Should have asked, where would I get the Dust Cap Replaced, or is it a DIY job?

ICBM

Probably DIY, but might be tricky. I'm not even sure where you'd get the cap from - although there must be somewhere! The originals become very fragile and brittle over time, and it's not uncommon to find cracked ones even if they're not pushed in, so they must get replaced by the people that do these things...

lamf68

I will make it a quest this evening. Cheers again mate, really helpful

jpfamps

Paul at Audioloudspeakers will have a suitable dust cap.

http://www.audioloudspeakers.co.uk/main.shtml

lamf68

And it's raining help! cheers man.