Use Op-Amps to Make a LED Color Organ

Collin Cunningham’s awesome videos are always great to watch. This time, Collin shows how to build a Color Organ, which is a light display that responds to sounds around it, allowing you to build cool visualizer effects to go with your tunes.

Long before the dawn of digital music, folks employed the power of the electric color organ (aka “light organ”) to add some synced visuals to their hi-fi experience. Schematics for building such a beast based on AC power and incandescent bulbs can be be found fairly easily on the web, but plans for comparable LED-based designs seem a bit harder to come by.

Adapted from Aaron Cake’s 3 Channel Spectrum Analyzer, I built my own analog LED Color Organ to enhance the aural experience. The circuit uses 4 operational amplifiers plus ultra-bright 5mm LEDs to respond visually for bass, mid, and treble frequencies.