The Physics of Sound Waves in an Ellipse

This computer simulation by Jason Schattman shows the beautiful wave patterns that emerge when a sound wave originates from various points in an oval-shaped echo chamber. It’s well known from physics that if you stand at one focus of an elliptical room and whisper, the sound will converge at the other focus, so that a friend standing there could hear you as clearly as if you were right next to them. But what happens if you whisper from somewhere else in the room? Like somewhere along the wall? Or dead center in the room? The wave patterns are surprisingly intricate, and beautiful to behold! I coded this animation using the Processing programming language. You can download the Windows application from When running the program, click anywhere inside the ellipse to create a new sound wave. With sliders, you can also change the aspect ratio of the ellipse, from string-bean thin to perfectly circular. Here are some other math animations from my channel ********************************************************* On the beautiful geometry of imaginary numbers & complex functions (can be enjoyed even without knowing what that means) All 6 trig functions on the unit circle Mathematical art using the idea of epicycles Optical illusions made using trigonometric functions Fancy “card tricks“ animated using mathematical pretzels (called Lissajous curves) Sound waves in an oval room: Fly through the 3D Sierpinski pyramid: Drawing on a spinning white board: