WOODEN DIDGERIDOO

Tunning of the Overtones

During my research and experiments on didgeridoo acoustics, I realized that the tuning of the overtones is a good indicator of a didgeridoo’s quality. I observed two major effects of overtone tuning on the notes of the harmonic series.

1 – In terms of tone: the harmonics corresponding to the overtones are amplified in the drone. This results in a clearer, more defined tone. Conversely, when the overtones are not in tune with the notes of the harmonic series, the harmonics of the drone are not amplified. The tone is then rougher, gravelly, earthy… Which has its own charm, too !

2 – Regarding the lips: There is less tension, and the effort required to vibrate is reduced. Lip vibration is more stable and easier to maintain. Articulation is therefore easier to execute in both slow and fast passages. Conversely, when the overtones are not in tune with the natural harmonics, this creates tension in the lips. The lips may even constantly oscillate between two similar vibration modes. It then becomes more difficult to maintain a stable vibration, and this becomes very tiring for the lips. Articulation also becomes more laborious.

A Few Notes on Instrumental Acoustics :

Overtones : These are the various vibration modes that are higher in pitch than the drone—the sounds of trumpets.
Depending on the didgeridoo, you can play 2 to 3, or even 4 or 5 of them. 

The Harmonics of drone : The sound of the drone consists of the fundamental frequency and all the multiples of that fundamental. The combination of the amplitudes of these harmonics defines the instrument’s tone.

Air Column Profiles

Based on these tuning principles and using acoustic modeling software that I developed, I designed original air columns, some of which include resonance chambers. In addition to tuning, these chambers add compression, dynamics, and stability to the sound. It takes some getting used to at first, but you quickly adapt and come to appreciate it.

The diameter just past the mouthpiece is also important.
For instruments intended for more rhythmic playing (the “OCTAVE2” series), this diameter ranges from 36 to 40 mm.
For instruments intended for more harmonic playing (the “EUPHONY” and “SERENITY” series), this diameter is at least 45 mm.

Through my various experiments, I have been able to define three series of instruments with distinctly different acoustic and dynamic characteristics (a fourth is in the works).

SERENITY : Quarter-Octave Overtone – A stable, deep sound, full of roundness and warmth

EUPHONY : Third, Octave, Fifth Overtones – Harmonious sound and fairly dynamic playing

OCTAVE2 : Octave-Octave-Third Overvibration – Precise articulation, powerful sound, and highly dynamic playing

If you don’t find what you’re looking for among these three lines, please let me know what you’re looking for. I can explore other types of air columns.

Manufacturing Method

Craft my didgeridoos using woodturning and milling.
These tools allow me to achieve precision and consistency in my work.

Local Wood

I use European woods, primarily ash. I appreciate this wood for its hardness, stability, grain pattern, and availability. Next are three very similar woods that are less readily available: service tree, serviceberry, and pear. I appreciate their density, fine grain, and soft hue.

Oiled Finish

I’ve decided not to varnish my didgeridoos but to oil them instead.
Linseed oil allows the wood to breathe and preserves the pleasure of touching the wood.
This finish requires maintenance on the part of the musician (see the following paragraph).

To ensure your didgeridoo has a long life, here are my care tips

• Keep away from heat sources: radiators, picture windows, and especially not in a car parked in direct sunlight !

• Apply oil  (flaxseed or canola oil) regularly to both the interior and exterior. The frequency depends on how often you use it. 
  At least once or twice a year is the minimum. The mouthpiece requires more frequent oiling. Right after oiling the inside, you’ll notice that your didgeridoo’s sound is significantly brighter. This can serve as motivation to maintain your didgeridoo.

• Use disinfectant essential oils to limit bacterial growth, especially right around the mouthpiece. It’s normal for this to happen—the heat and moisture from our breath provide a breeding ground for bacteria. By wiping the inside of your didgeridoo with a cloth and spraying it with an essential oil-based disinfectant (you can find these at pharmacies), you won’t have any problems in this regard.

• Store your instrument in a dry, well-ventilated place.