The Spiral Didgeridoo – A Wood Aerophone Innovation.
The spiral didgeridoo is a modern type of non-traditional didgeridoo. The length of the didgeridoo is curled into a spiral, and is designed for portability – hence it is a type of travel didgeridoo. It has the same drone sound as the traditional didgeridoo, but the spiral didgeridoo is an innovation because it is not a Eucalyptus branch hollowed out by termites.
The spiral didgeridoo has several other names, including spiral didge, spiralidoo and didgehorn. Like the traditional didgeridoo it is classified by musicologists as an aerophone.
Parallels to natural horn
The spiral didgeridoos shape is similar to the natural horn. The development of the spiral didgeridoo has parallels to the development of European horns, which also evolved from an elongated cylinder pipe to a spiral pipe shape for the same reason of portability - and so the pipe has no loss of overall length or sound qualities but is in a more convenient and compact form.
Playing technique and general musical characteristics
The instrument comes in various musical keys, including C, C#, D, E, F, and G. When played, the spiral didgeridoo can be held by both hands for stability, with the forward hand on the outer rim, and the fingers of the bottom hand placed in the open centre. It can also be held in one hand which enables the player to use the other hand for playing other instruments, or be mounted on a stand to enable the freedom of using both hands on other instruments while simultaneously playing the spiral didgeridoo.
It is played in the same way as traditional didgeridoos and circular breathing can also be used to create continual sound. In comparison to the normal didgeridoo the spiral didgeridoo requires less breath pressure to play because of the increase in back pressure created by the spiral of the pipe increasing air friction. This means that the spiral didgeridoo is easier to play than the traditional didgeridoo because it does not require as large a lung capacity as the traditional didgeridoo.
The primary drone sound is generated by the vibrating lips, and the spiral pipe amplifies the sound. The embouchure is also the same as traditional didgeridoo, and pitch variation is achieved by modulating the lip tension. Overtones are also created with the spiral didgeridoo by changing the mouth geometry and tongue position, and the vocal tract is used to increase the tonal variation and make sounds.
Construction and materials
The basic shape of the spiral didgeridoo is an Archimedean spiral with a flared exit of the pipe. Spiral didgeridoos are usually constructed by sawing a selected block of wood into two halves; carving out the hollow spiral pipe; and gluing it back together to form the basic instrument. They are usually made in Indonesia, and can be plain or decorated. The two woods most commonly used for the instruments construction are jackfruit, Artocarpus heterophyllus, which has yellow coloured wood; and, sono, Pterocarpus indicus, which is a dark coloured wood.
There are two basic shape types of spiral didgeridoo: an open centred type which allows the didgeridoo to be held with the fingers of one hand through the centre; and a closed centre type which directs the sound to the pipe exit side of the instrument. Like traditional didgeridoos, the mouthpiece can be modified with beeswax to suite individual mouths and playing styles.
· Books LLC, Natural Horns: Didgeridoo, Alphorn, Bugle, Lituus, Shofar, Lur, Shankha, Conch, Natural Trumpet, Salpinx, Vuvuzela, Natural Horn, Post Horn. 2010, Books LLC, ISBN 1155470141.
School of Physics, Brass instrument (lip reed) acoustics:
an introduction, School of Physics, University of New South Wales, Sydney.
School of Physics, Didgeridoo acoustics/yidaki acoustics,
School of Physics, University of New South Wales, Sydney.
Tarnopolsky, A., Fletcher, N., Hollenberg, L., Lange, B.,
Smith, J., Wolfe, J., The vocal tract and the sound of a didgeridoo.
Nature, Vol. 436, July 7 2005.
· Tarnopolsky, A, Fletcher, N. Hollenberg, L., Lange, B., Smith, J. and Wolfe, J. Vocal tract resonances and the sound of the Australian didjeridu (yidaki) I: Experiment, J. Acoust. Soc. America, 2006 119, 1194-1204.