How do I switch the power on/off via a relay ?

Question

I have a subwoofer plate amplifier for the home. Of course it operates on 120VAC. How do I trigger the amp on when it senses audio (AC). I know most plate amps have this feature built-in, but this one doesn't. I am trying to do this on a budget. Any procedures or gadgets would be helpful.

Answer 1

You wold have to have an audio sensor (basically a voltage sensor) on the subs signal, then have it trigger a power relay on you subs power. It would take a bit of skill to make.

You could buy an audio sensor here

http://catalogs.infocommiq.com/avcat/CTL...

and hook up a relay to your sub.

It would be cheaper to sell your current plate amplifier and get one that has that feature.