Chladni Sound Figures
Around 1800, Ernst Florens Friedrich Chladni travelled through Europe and fascinated people with his plates that make sound visible. He sprinkled sand onto metal plates that were firmly fixed in the centre and made them vibrate with a stroke of his violin bow.
Some frequencies manifest on the plate in a standing wave, which makes it vibrate more in some places than in others. In the dormant areas on the plate, the sound draws beautiful symmetric patterns as the sand comes to rest there. Less motoric sensitivity is needed for the Chladni box, whose plate is stimulated by a loudspeaker instead of a violin bow. Certain sounds were chosen beforehand and could be played at the touch of arcade buttons. The fluorescent sand first jumps wildly on the dark plate, until after a few seconds clear, shimmering lines appear.