April

Percy Aldridge Grainger (1882-1961), Kangaroo-Pouch Method of Synchronising and Playing 8 Oscillators

Artist: Percy Aldridge Grainger 1882-1961

TitleKangaroo-Pouch Method of Synchronising and Playing 8 Oscillators

Date: April 1952

Medium: ink and watercolour on unidentified chemical print

Grainger Museum, University of Melbourne, Australia

EMu user since 2012

Percy Aldridge Grainger (1882-1961), Kangaroo-Pouch Method of Synchronising and Playing 8 OscillatorsDuring the 1940s and 1950s Grainger and his friend, physicist Burnett Cross, collaborated on a number of so-called ‘Free Music’ experiments. They created electrical instruments that predated electronic musical instruments such as synthesisers. Grainger’s expressed aim was music freed from the conventional restrictions of pitch, rhythm and musical form, as well as removing the need for a performer in the conventional sense.

The ‘kangaroo pouch tone-tool’ was one of a number of experimental musical instruments made by Grainger. This illustration is a concept drawing of a more complex version of an instrument of this name and type on permanent display in the Grainger Museum.

The illustration shows a paper music “score”, wrapped around two cylinders (recycled carpet-roll tubes), which sit on platforms with casters. The tubes are rotated making the score move from right to left. The score consists of a base layer of paper overlaid with eight paper graphs (carefully colour-coded in the illustration by Grainger): four to control pitch and another four to control volume (“tone-strength”). Each graph individually raises and lowers a small mechanism consisting of an arm linked to an oscillator. The oscillators were to be wired to an amplifier and speaker. As the waves in the paper rolls move through the machine, changing the position of each oscillator, the relative pitches of the instrument’s four ‘voices’ alter, creating four sliding tones sounding at the same time.

Acknowledgements

Photographer: Lee McRae