Draw a Shape, Hear a Drum
Every shape has a voice — and drums only beat the ones you draw.
🥁 Shape-to-drum synthesizer
Draw a closed shape below — round shapes get a deep thump, spiky ones get a brighter crack. Strike on release.
How it works: your shape is treated like a drum head. The physics is simplified — bigger head → lower pitch, rounder → purer tone, pointier → brighter overtones. Fully on-device sound, no audio files.
Why people love it
There's something quietly magical about turning a doodle into a drum. People love this idea because it makes music feel physical and personal: you are not choosing a preset, you are sculpting an instrument. The original, Eigendrum, solves a real math problem — the wave equation for a drum membrane — to map any 2D shape to the sound it would genuinely make. Circle? A deep, clean boom. Long skinny shape? Higher and thinner. Blobby scribble? Somewhere in between, weird and wonderful.
Reddit loved it because it is instantly fun and endlessly repeatable — no tutorials, no labels, just a pen and a thump. It also secretly teaches acoustics: you start hearing the geometry in everyday drums, guitar bodies, and even rooms. People drew hearts, spirals, cartoons, and their own names just to hear what they'd sound like.
This demo approximates the same physics in your browser (area and roundness set the pitch and brightness). Try a circle, then a spikey star — the difference is all in the shape.