Tomorrow the library's summer reading program special event is "Didgeridoo Down Under," an Australian themed program. Well, what is a didjeridu or didgeridoo?
The didjeridu is the main musical instrument of the Aboriginal peoples of Northern Australia. The instrument is simply a hollow tube of wood that becomes a sophisticated wind instrument in the hands of a skilled player. Traditionally, it was not used as a solo instrument, but as an accompaniment to vocal music.
The actual instrument is made from a piece of wood or bamboo, about 4 or 5 feet long, usually a natural branch. Eucalyptus that has been hollowed out by white ants is considered ideal. The open wooden tube is blown at one end. Sometimes there's a mouthpiece of wax, clay or hardened gum used to hold the player's lips as they vibrate as with a modern brass instrument.
The didjeridu only plays 2 notes, a fundamental and an overtone a major 10th higher, an acoustical oddity. The usual explination for the overtone at the 10th is the differences in diameter at parts of the tube, coming from a natural branch.
Soaking the instrument in water is said to make a mellow tone, while playing a dry instrument creates a flat tone that does not carry well. Sometimes water is poured down the inside of the tube if the instrument dries out while it is being played.
Technique goes beyond the vibrating lips. The overtone is produced by lip pressure. Tongue movements create intricate rhythmic patterns. Different tone colors come from altering the shape of the mouth cavity and the position of the tongue.
The didjeridu is a combination of a drone and a rhythm instrument. The sound must continue, so breathing must continue for a continuous air stream. Breathing is done through the nose, with extra air stored in the cheek and pharnyx to be used while the player is breathing.
Additionally, the player makes hummed chords against the drone, and uses various types and styles of toungings, as well as changing color and timbre, providing a varied accompaniment for the singer and the song.
In the hands of a skilled player, the didjeridu is a very sophisticated instrument, even tough it comes from a simple branch.
More information on the didjeridu (or didgeridoo) and Australian music in general can be found in the Polley Music Library.