How do didgeridoos work?

Forged by nature and steeped in tradition, the didgeridoo is a triumphant symbol of Indigenous Australian culture

(Image source: Pixabay)

If there is one musical instrument that instantly evokes an image of a country, then it
is the didgeridoo. The instrument may well have been embraced worldwide and featured in all manner of music genres, but the gnarly, traditional didgeridoo will be forever remembered as an Australian invention.

The didgeridoo is widely believed to be one of the world’s oldest instruments, with some educated guesses placing its origins back to Australian natives 40,000 years ago. Tradition states that ancient tribes would use the didgeridoo’s versatile sound to tell stories and orchestrate dances. Players would perform without pause for hours using a technique known as circular breathing, punctuating the consistent drone with yelps and grunts that would reverberate and boom from the instrument. So entrenched is the didgeridoo to native culture that even their mythological gods embraced the instrument’s unique sound for their dance as they built the world.

If the didgeridoo was around when nature was created, then it is only fitting to learn that the instrument is hand-carved by nature itself. The traditional wood of the instrument is the eucalyptus tree, which often plays host to termites. Unfortunately for the plant the insects feast on its trunk from the inside out, hollowing them and leaving holes that puncture the exterior. But through their feeding the termites sculpt an instrument. All humans must do is find the right tree, chop it to the correct length and tighten the blowhole. Then they’re ready to play.

Making the sound

1. Creating the instrument

The natural shape of the didgeridoo will result in some sound frequencies being stifled while others are amplified, producing an eclectic series of sounds. Hot wax can be used to narrow and seal the periphery of the blowhole to minimise sound loss.

2. Circular breathing

When their lungs are saturated with air, the player will exhale as normal.

3. Puffing up

As their breath begins to wane, the player will puff their cheeks full of air and seal off the back of their mouth.

4. Inhale

The player can now inhale through their nose while maintaining the exhalation of air stored in their cheeks

(Illustrations by Nick Sellers)

This article was originally published in How It Works issue 120, written by James Horton

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