How do I link the output of a P.A. circuit to a light-controller for a LED array?

I am planning a costume build in which a public-address source needs to flash LED lights in the costume to the waveforms played through the public-address circuit. Additionally, since this is a costume project it needs to be portable and somewhat resilient to shock.

Sandisk1duo8 years ago
so a circuit that responds to light?
jeff-o8 years ago
Easy enough. You need a microphone and a small amplifier (an op-amp or transistor would work fine). The output would be rectified using a regular diode, then fed directly to the LEDs. As the sound waveform rises and falls so does the voltage to the LEDs, causing them to light up. If you are looking for more of a "VU" meter effect, there are special microchips that do specifically that - do a google search and you'll find dozens of projects.