The didjeridu (also spelled didjeridoo or didgeridoo) is a musical instrument that is an important part of the traditions of the Aboriginal people of northern Australia. It is a simple aerophone consisting of a long hollowed tube shaped to create a mouthpiece at one end. The instrument is usually made of wood, but is considered to be in the brass family (sometimes called the "lip- reed" or "cup-mouthpiece" family) because, as with all "brass" instruments, its sound is created by buzzing the lips against the rim of the mouthpiece.

Figure 3: A didjeridu made in the traditional way is always a unique work of art, reflecting both its original natural shape and the musical and visual tastes of those who shaped and decorated it.

(a) (b) (c)

The typical didjeridu consists simply of a tube with a mouthpiece at one end. The tube is traditionally made from a termite-hollowed eucalyptus tree. (Sometimes a branch that is large enough and straight enough can be found, but more commonly, it is the trunk of a young tree.) When a hollow tree of the right size is found, the bark is removed, and its innards may be further hollowed and shaped to produce a better sound. The outside of the instrument may be painted and/or varnished. Some modern instruments are made of other materials, such as bamboo or other kinds of wood.

The traditional instrument has no fingering holes, keys, valves, or slides. Some modern didjeridus have a slide construction similar to a trombone, or even saxophone-style keys that allow a melody to be played, but these are unusual.

The typical didjeridu is between one and two meters in length, but some are longer than three meters. As with any wind instrument, larger and longer didjeridus produce lower sounds than smaller instruments. (See Wind Instruments: Some Basics for an introduction to the acoustics involved.) Some instruments have a more conical shape and some are more cylindrical, and this also affects the sound of the instrument.

The rim of one end opf the tube is altered slightly to form the mouthpiece. If one end of a didjeridu is already the right size and shape to accommodate the lips, simply smoothing it out to make it comfortable is often enough to create a mouthpiece. In many instruments, though, a layer of beeswax is added to the rim. The consistency of the beeswax, which becomes malleable at warm temperatures, makes it ideal for shaping a comfortable, efficient mouthpiece. The diameter and thickness of the rim are similar to the rim of the mouthpiece of a low brass instrument such as the tuba or trombone, and the technique for getting a sound is quite similar. In this family of instruments, the sound is created by "buzzing" the lips inside the mouthpiece rim.

The didjeridu originated in northern Australia. In fact, it can be considered a family of instruments, since several different native groups have a specific local version of the instrument, with a local name. (Aboriginal Australians come from a variety of related cultures, with different languages and customs, not a single uniform culture.) A didjeridu made by the Yolngu people, for example, is a yirdaki. The term didjeridu is apparently a Western coinage, and is a generic name covering all Australian instruments of this type.

It is an ancient instrument, in the same category as other traditional lip-reed wind instruments, made from a variety of materials, from branches to animal horns to conch shells, and found in many cultures around the world. Archaeological records show the didjeridu is at least 1500 years old, and it may be much older than that, possibly even one of the oldest wind instruments ever invented anywhere.

Figure 4

Didjeridu traditions center in Arnhem Land, the largest Aboriginal freehold area in Australia. It is located at the "top end" of Australia's Northern Territory (its north central state). There are actually three distinct musical traditions in this area, which include different didjeridu playing styles. For example, in eastern Arnhem land, players tend to alternate rapidly between the two easily-available pitches (see below); in the central area the alternation between the two is slower, and players in the Western part of the area tend to play only the fundamental, deriving interest from variation in timbre and other techniques (Listen to the audio file above for more about this).

Some musical events in Australian Aboriginal communities have intense religious and cultural significance and are not open to the public; specific instruments and players are called for on these occasions. Other events are open-to-the-public performances. Although playing the didjeridu is traditionally considered a man's job, and Aboriginal people may consider a didjeridu-playing woman to be shocking or humorous (in the same way that an American might consider it shocking or humorous to see a man wearing a dress), there are no particular proscriptions against outsiders playing the instrument.

In fact, in recent times, the world music movement has created widespread interest in Non-Western musical traditions, including instruments such as the didjeridu, which now are sometimes included in cross- tradition ensembles. As of this writing the band Yothu Yindi has had the greatest impact in introducing the didjeridu to the rest of the world. Most Aboriginal Australians have no problem with the idea of the instrument being used in non-traditional ways, but some are troubled by the mass production of poorer-quality, inauthentic instruments, and by schools of playing that claim, but do not really have, a link with Aboriginal traditions, considering this to be a form of intellectual-property theft from their culture.

Traditionally, a single didjeridu player accompanies one or more singers. The singers may also be playing percussion instruments, such as bilma (clapsticks), and there may also be dancing. The didjeridu player learns the repertoire from other accomplished players rather than reading music. Boys and young men are encouraged to play the instrument for fun, and the most promising ones are trained to become the community's didjeridu players, the ones who are asked to play at ceremonies and performances. The most typical kind of performance is a series or cycle of short songs; each song has its standard rhythm, and the didjeridu player is expected to both keep the basic rhythm and to improvise variations on it, somewhat as a good jazz drummer would.

The typical sound of a didjeridu is a low, buzzing drone. Some playing styles stay on this low pitch most of the time; other styles alternate between the low pitch and an overtone which sounds a tenth (an octave and a third; see Interval for more information) higher than the basic drone pitch.

In order to keep up the rhythm pattern effectively, didjeridu players use a technique called circular breathing, which allows them to breathe in through the nose while they are still blowing through the instrument with their mouth. This allows the player to produce a continuous sound. Some players of other low brass instruments also learn circular breathing, but the technique is somewhat tricky to master and physically strenuous, and didjeridu is the only instrument which uses it as a matter of course.

Composers and arrangers who want to add a "world music" component to their sound may be interested in the didjeridu. In spite of its low range, the sound of the didjeridu is very noticeable because of the buzzing timbre and percussive playing style.

Note that most didjeridus cannot be tuned. A serious didjeriduist will have several instruments of different pitches, but do not expect the didjeridu to be able to produce a particular pitch, or play anything resembling a melody, unless you are familiar with the instrument available. If the other instruments, in the group that you are writing for, are easily tunable (guitar and bass, for example), you may be able to ask them to tune to the didjeridu.

Didjeridu can be used very effectively as a bass drone, particularly if the other instruments in the group can adjust their tuning. The fact that the player does not need to stop playing to breathe can be used to create interest and build tension. Although this is a wind instrument, an accomplished player may best be thought of as a very useful addition to an ensemble's "rhythm section" (somewhat as a string bass player in a jazz rhythm section), providing both the bass note and a steady, interesting rhythmic pattern, as well as producing surprising variations on the pattern. To the Western listener, the standout timbre and unique "wind percussion" effects of the didjeridu are strongly evocative of the "exotic" in general, and Australia in particular, and can be used to suggest a surprisingly wide array of moods, from "primitive" to "world-music modern", and from "earthy" to "atmospheric".

The author is grateful for the cooperation of the University of Illinois Urbana-Champaign (UIUC) School of Music and the Robert E. Brown Center for World Music, and particularly for the assistance of Phil Clark. A graduate student in ethnomusicology at UIUC, specializing in Australian music, Mr. Clark provided information as well as playing didjeridu for the video and audio recordings in the lesson, and allowing his instruments to be photographed.

This lesson is just an introductory overview. As of this writing, the following sites included much more in-depth information on the didjeridu:

Neville Fletcher's journal article, "The Didjeridu", in Acoustics Australia, Vol 24, pp 11-15 (1996) (available on-line here) is only one report from numerous investigations into the acoustics of the instrument.