Solid state relay to control led lighting?

[devestator_x]

Ok, so I had this idea. You know how they make those cheap led controllers that have a built in microphone and when you turn up the music the lights just stay on? Well, what if you could tap into the signal output from your stereo (or amp) and use that AC current as a turn on signal to flip a relay? Well after some internet searching, it seems what i am thinking of is called a soild state relay and somehow it can do just that, use an AC current as a turn on signal and switch a DC circuit on and off. They work super fast, like measured in miliseconds. Problem is I really have no idea what to look for in terms of power handling or exactly how to wire it once I get it.

Just thinking there has to be a better way to control lighting than those overly sensitive mics.