I am not an amp tech

[Pea Turgh]

My mate had an old Laney CP12 powered wedge.  100 watts in to 8ohms.

He said it needed a new speaker, asked me if I wanted it for parts.

Fired it up - seemed ok.  A bit crackly.  Sprayed a bit of cleaner in the pots, left it a few hours.  Switched it back on, played bass through it for a bit.  Crackles got a lot worse, then made some really loud pops.

 I’m thinking a blown speaker would just make farting noises, but this still had what appeared to be a full frequency spectrum (with added random nasty sounds)

Checked all the internal connections - all good.

Switched it back on, no sound from the input, maybe mains frequency buzz and smoke started to emulate from the back of the driver.

I’m thinking it’s the amp unit rather than the speaker (at least until smoke came out of it 😂).

 

Does anyone recognize these symptoms?  Is it an easy fix, or is it definitely dead?  I know it’s probably not financially viable for a tech to do, and possibly quite dangerous for me.  Maybe I just want to understand what went wrong so I could learn to let it go!

[Downunderwonder]

I am also not an amp tech. I surmise the anp must have been sending DC to the speaker to get it smoking as you describe. I would be very surprised if any of it is now worth salvaging.

[neepheid]

The magic smoke has been let out, sad times

[Pea Turgh]

8 minutes ago, neepheid said:

The magic smoke has been let out, sad times

It was!  The driver and amp looked like alright bits of kit!  Would have made a nice practice amp.

 

I would like to understand what went wrong, so any suggestions are very welcome.