Bernoulli levitation, or aerodynamic levitation, is a great physics demonstration. You've probably seen it before. The classic demonstration is: take a hair dryer, point it straight up, and put a ping-pong ball in the stream of air. The ping-pong ball floats in mid-air. But, most hair dryers are loud. I want to find a way to do this demonstration quietly, so that I can talk to my students more easily while the ball is levitating. Or, maybe set it up as a display on my desk and just leave it running continuously. So, does anyone know of a good way to do this quietly? Should I build a soundproof shield around the hair dryer? Is there another device instead of a hair dryer that produces an air stream quietly?