Amp DC Detector / Protection

Hello, anyone did DC detector with a comparator and a ref voltage ?. Something like this.
( two op amps for + and - rail detection. )
Even at 40v at 5 hz won't " trigger it " so no false dc detection.
 

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You need bipolar caps ideally, and you must trigger on either polarity - the amp output could latch to either rail, both are equally disasterous for the speaker!

And it should probably latch off for a while (monostable circuit). When I was testing my speaker protect circuit I realized this would be handy. Mine also detects if the rail voltages are low so doubles as a de-thump circuit. I followed the circuit Doug Self describe in one of his great books.
 
Seems to work fine in " detecting " dc greater than 380mV either rail .
1. How fast it does it would depend on op amp speed ?. is this " worth " building ? or just for curiosity , learning .
2. Can you share your schematic based on Doug Self, I can't find it.

Thank you Mark for answering my "noob" questions .
- Bruno.


Will the input filter " upset " the amplifier ?. the 10uF in parallel ?. Second photo.
 

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