I used to have a small active PA system, including a crossover and two stacks of three Carver power amps. To make everything simple, I used TRS cables for everything... Speakers, interconnects, you name it. (Hey, I was young..)
Friends would love to help set this stuff up and break it down, most of them knew what to do and what not to do. As it turned out, at least one did not.
Connecting the input jack of a Carver amp to a speaker's input turns out to just not do anything at all, just like you probably would expect. Needless to say, I was very surprised when I turned the amp racks on and did not hear the signature POP and Hisssss sounds from my speakers.
These amps had little meters on the front, with a couple of green, one yellow and one red Clip LED. When that Clip LED came on, well, usually it was to the rhythem of the beats as "the party was hot and the bass was pumpin'" like we used to say. Looking at my amps a second or so after hearing the realays click, and not hearing the POP and Hissss, I noticed all amps had the Clip LED on solid...
the brain had just enough time to get to the signature "Uh" beginning of "Uh-oh..." when my ears were greated with a whole different POP, much louder than normal, and the hissing that followed sounded different too....
Turning around, I was greated by smoke from the crossover and equalizers. The EQ's still looked normal, lights on and all. The crossover was in bad state, it turned out it had actually caught on fire, caps had been blown out and the whole thing was mangled badly, found some parts smoking 10 feet away from the thing.
Now for the most amazing thing... The Carver amps self-protected and lived. The crossover and EQ blew up, but the 'Sonic maximizer', mixer and other stuff I head upstream all lived.
Friend in question claimed it was not his fault. After all, this wouldn't have happened if I had not turned the power on! My friend lived too, barely...
Niels.