Didge
A wind instrument you assemble
It started as a didgeridoo and the name stuck, but the model underneath is a wind instrument in general. Five exciters, twelve bores and five materials, and you pick each one independently.
- Type
- Physical modelling
- Formats
- VST3 · AU · CLAP · Standalone
- Systems
- macOS · Windows · Linux
- Version
- Source
- Licence
- GPL-3.0
Measured figures
- 5 × 12
- Exciters against bore profiles. Most combinations were never built in wood or brass.
- 16
- Waveguide segments in the bore, shaped by dragging its cross-section.
- 8
- Sections in the vocal tract, morphing through the vowels.
- 0
- Samples and oscillators. Everything is air being solved.
It is not really a didgeridoo
The name is where it started, not where it ended up. What is actually in there is a wind instrument taken apart into its pieces, with each piece left as something you choose.
The exciter is the thing that makes the air pulse: lips, a single reed, a double reed, a free reed, or an air jet with no valve at all. The bore is the tube it drives, and there are twelve of them (natural, cylinder, cone, flared, horn, trumpet, trombone, flugelhorn, french horn, tuba, alphorn, contrabass). The two are independent controls.
Pick an air jet on a cylinder and you have a recorder. A single reed on a cone is a saxophone. Lips on a trumpet bore is a trumpet, lips on a long natural bore is the didgeridoo it was named after, and a free reed on a tuba is something nobody has built because it would be absurd to try. The factory bank walks through the sensible half of that grid: clarinet, bass clarinet, recorder, pan flute, trumpet, trombone, flugelhorn, french horn, tuba, alphorn, reed organ, yidaki.
Solved as air, not modelled as a sound
There is no sample content and no oscillator anywhere. The bore is a sixteen-segment waveguide with scattering junctions, built from a radius profile you shape by dragging the cross-section on screen. The open end uses the standard radiation pair, so the bell radiates what it should and its high-pass corner follows its own radius.
The lip valve is a one-mass outward-striking model integrated with an unconditionally stable scheme, with the flow through the slit solved in closed form against the tract and bore impedances in series. The lips genuinely beat shut for part of every cycle, and that closure is where the buzz comes from. The cane reeds are the same machinery with the sign reversed: blown closed instead of blown open, which is why they behave so differently under pressure.
Loud waves travel slightly faster than quiet ones, so they steepen as they go. That is why a brass instrument turns brassy when you lean on it, and it is why this one responds to how hard you blow instead of just getting louder.
The part that makes it sound played
An eight-section vocal tract sits between the lungs and the exciter, morphing through the vowels on an x/y control, with a growl that beats against the drone at an interval you set. The glottis is frequency-dependent: open to the lungs down low so the breath passes, reflective at the formants so the tract resonates. The acoustics literature identifies exactly that partially closed glottis as the difference between an experienced didgeridoo player and a beginner.
Then the embouchure controls, which are the ones worth spending time on: lip tension, lip damping, aperture, bend range. And velocity can be routed to breath, to breath and attack together, to embouchure, or to brightness, because a player leaning into a note does not only blow harder, they tighten up and attack faster.
Everything it does
- Choose the exciter and the bore separately
- Five ways of making the air pulse against twelve tubes. Sensible combinations give you the instruments you know; the rest give you instruments that have never existed.
- Drag the bore to reshape it
- The cross-section on screen is the actual radius profile the waveguide uses. Pull the bell open, narrow the throat, add flare, and the spectrum below it moves as you do.
- A vocal tract that matters
- Eight sections morphing through the vowels, with a frequency-dependent glottis: open to the breath down low, reflective at the formants. That is the thing that separates a player from a beginner on a real didgeridoo.
- It gets brassy when you push it
- Loud waves steepen as they travel, so hard blowing changes the timbre and not only the level.
- Reeds behave like reeds
- Cane reeds are blown closed and lips are blown open, which is a sign change in the same model. It is why a clarinet chokes when you overblow it and lips do not.
Specifications
| Type | Physical modelling |
|---|---|
| Exciters | Lips, single reed, double reed, free reed, air jet |
| Bore profiles | Natural, cylinder, cone, flared, horn, trumpet, trombone, flugelhorn, french horn, tuba, alphorn, contrabass |
| Bore shaping | 16-segment waveguide, drag the cross-section to reshape it |
| Materials | Wood, bamboo, brass, steel, glass |
| Vocal tract | 8 sections, vowel morphing, growl with a tunable interval |
| Embouchure | Lip tension, lip damping, aperture, bend range |
| Breath | Pressure, attack, release, vibrato, breath noise, optional decay and sustain |
| Velocity routing | Off, breath, breath and attack, embouchure, or brightness |
| Nonlinearity | Wave steepening with amplitude, and turbulence scaled to the pressure drop |
| Formats | VST3 · AU · CLAP · Standalone |
| Systems | macOS · Windows · Linux |
Download
macOS builds are not notarised yet — right-click the plugin and choose Open the first time.