Dc voltage sent to my speakers

Recently while listening to my set up my speakers started literally smoke .My crossover and drivers are fried 

I curious what causes DC voltage to go the speakers,?


Oh, forgot one, often BJT amps will also have some sort of thermal runaway protection.  Otherwise, no I haven't seen a lot of SS amplifier schematics with "turn off on DC" on the outputs.

But, I'm not a tech, just a hobbyist who stopped pouring over schematics a long time ago.

Um, not the one's I've seen especially "high end" amplifiers that pride themselves on not having any.


Sounds cringeworthy to me- yikes!

If you want fancy amplifier output protection you need to stick to Class D. 

Not really joking but looking at the Hypex and ICEpower spec sheets they have a lot of fault detection and shut down circuitry built in that most linear amps never even think of.  Maybe the need to target pro sound helps them build paranoia into each amp?

My DIY amp went south a while ago. Not sure if it was the emitter resistor that shorted and caused the output transistor to fail, or vice versa.

Thankfully, I had installed protection boards on the outputs, so speakers were spared.

Had they not been there, the speaker would have been toast.

It’s a 30w class an amp, so there was only around 30vdc, but would have blown the speaker for sure. Rail voltages can go waaaaay high in high power amps, so should something fail, it could get dramatic.

Sorry this happened, a costly episode no doubt.

Should you buy a used amp again, one that doesn’t have DC protection, or some other kind of fuse on the output/rail, then any tech should be able to install DC protection for not very much money.