Draw any shape in your browser and play it like a drum

Eigendrum lets you sketch any arbitrary 2D shape in your browser and instantly hear its resonant acoustic frequency mapped as a playable physical drum.

Here's the gist: the web app covers your drawing or mathematical equation in a mesh of triangles, solves the underlying wave equations right on your device, and synthesizes the sound. Everything runs locally in the browser with no sign-ups, no backend servers, and zero install steps.

Why it matters: Simulating how arbitrary custom shapes vibrate usually requires specialized physics software. Eigendrum runs the finite element solver in real time while keeping error under 0.1% against exact theoretical benchmarks. Striking different spots excites different vibration modes, letting you test real-world acoustic physics or play historical math paradoxes like Kac drums—two completely different 2D shapes proven in 1992 to sound identical.

You can trace shapes by hand, type polar equations like 1 + 0.3cos(5t) directly into the address bar, or click a single frequency row to hear individual standing waves a physical mallet could never trigger alone.

Turns out you can't always hear the shape of a drum, but drawing one is a great way to learn physics fast.