Didgeridoo tuning by shortening the instrument


Didgeridoo tuning is unlike any other instrument tuning, but, hey, the didgeridoo is an instrument of its own kind.
On the page on didgeridoo sound you will find that

"Every genuine didgeridoo has its own spirit, a uniqueness arising from
  1. the inside configuration and measure as the aftermath of termites' feast,
  2. the species of the tree, more precisely,. its density,
  3. the thickness of the walls, thick enough not to crack, thin enough for good resonance,
  4. the length of the didgeridoo, real and adjusted by the third of the base diameter,
  5. the ratio of the top and base diameters, the taper and more...

The didgeridoo sound is determined by these objective factors apart from the subjective: the didgeridoo player or puller. The first two contributing elements are given by Nature, but the last three elements can be attuned, more or less, by the expertise of an accomplished craftsman, the didgeridoo maker."
If you have bought a finished didgeridoo instrument you can work only on point 4. and - maybe to some degree - on point 5. to tune up (down?) your instrument.

Some didgeridoo shops are claiming that they adjusted the base sound of the instrument to the correct pitch of its musical key. But did they, could they do that?

"What makes the unusual mixture of didgeridoo sounds is the very strong and varied interactions among
  •   the basic sound and the overtones of the didgeridoo,
  •   the buzzing vibrations of the player's lips and
  •   the vocals produced in the player's vocal tract."
    (Buy didgeridoo for its sound qualities)
If the above is true (just look up a basic how to play the didgeridoo lesson to find in the text these same words as the proof for the above statement), than they could not tune the didgeridoo for you, because they could not adjust for the buzzing of your lips and the vocals of your vocal tract.(Actually the didge is an amplifier to your vocal tract not someone else's! In this respect, didgeridoo playing is unique: nobody can repeat you, not even on the same particular instrument.)

You are the one who can make the correct tuning of your didgeridoo, but do not hurry: wait untill you are really familiar with your instrument, it is totally acclimatized, and the timber is properly seasoned and you know what and why are you doing it.
Just note that the physics of the didgeridoo excludes the possibility to absolutely tune the instrument - tuning the fundamental tone does not tune the overtones, difference sounds, vocals and vice versa.

By cutting off slices from the base of the didgeridoo you make the pitch of the sound higher. Tuning a didgeridoo is very similar to amputation, so you have to think twice before going ahead with it:

  •   the cut-off piece is gone forever,
  •   the tuning can be done only upwards to the next higher base tone.
  •   You may ruin a perfectly good instrument, with little or no gain at all!

STEVEN KNOPOFF in ACCOMPANYING THE DREAMING Determinants of Didjeridu Style in Traditional and Popular Yolngu Song: The lack of precise tuning of the didjeridu's pitches is a normal feature of traditional Yolngu song, but can cause problems in the pop/rock context, an unwanted perception of 'out of tunedness'. Because of this, in their pop/rock songs Yothu Yindi's studio engineers alter the pitch of the didjeridu's blown fundamental technologically...

If you go ahead with it anyway, be on the safe side; cut off smaller slices and repeat the cut with even smaller slices, if it needs more shortening. If you cut off to much, you have to go to the next higher note...

Much better way, but applicable only for some instruments, is to make the opening at the base of didgeridoos wider, using a chisel or file. This method makes the didgeridoo a more responsive instrument, its sound clearer and louder. And by making the base wider is the only way to fine tune a didgeridoo downwards (remember: by shortening it, you do the didgeridoo tuning upwards to the next higher tone).

For most didgeridoo players the exact musical key is not a concern at all. For a pvc or mechanically bored timber pipe it is only a matter of measure and cut to achieve an exact pitch. Termite hollowed eucalyptus didgeridoos have a spirit, a unique didgeridoo sound one should associate with and cultivate.