The homemade didgeridoo: An ancient acoustic resonator.

The didgeridoo is an ancient Aboriginal instrument traditionally crafted from Eucalyptus trees which have been hollowed out by termites. The instrument is an excellent example of a simple one‐dimensional acoustic resonator with a fundamental resonance corresponding to one‐half wavelength. Today, the ubiquity and low cost of PVC pipes make didgeridoos inexpensive, easy to find, and trivial to construct from materials found at any hardware store. Students will have fun learning to make sounds with the instrument—perhaps they will even learn the technique of circular breathing—all while exploring fundamental principles of acoustics. As further investigation students can hum as they play, resulting in “beats, the speed of which can be adjusted by changing the pitch of the hum.