Graeme Gerrard: Strings Of Token Strings (1984)

Abstract

"This piece was composed using COMPOST, a computer programming language for music composition, written by the composer. The piece was synthesised on a Vax 11nso computer using the MUSIC4BF sound synthesis program, and mixed at the La Trobe University music department studio. Several months were spent in developing the palette of sounds employed in the piece. As the title may suggest, a primary goal was the simulation of various timbres and textures that might be heard from a string orchestra. The starting point for the development of these sounds was a frequency modulation algorithm which uses a complex modulating wave, consisting of three component sine waves to modulate a single sine carrier wave. Various 'micro-modulations' were added to the amphtude and frequency components of each wave, and data from measurements were used accurately to simulate such elements as amplitude envelopes, ensemble timing, plzzicaw durations and trill rates. The result' ng signal was then fed thro 1gh other programs for choru fog, spatial n.anipulation and reverberation. The various parts of the score were genera ea and processed by the COMPOST language. A feature of this language is that the elements of a piece are repreented symbolically as 'tokens'. The composer can specify how a score element is to be generated, transformed and finally arranged in relation to other score elements. In Strings of Token Strings a random pitch series with a prescribed contour (see Figure 21) was generated and this became the source material for a considerable part of the piece. A number of transformations was applied to this series, for example the intervals were expanded by multiplication, inverted and retrograded; the pitches were re-ordered and 'verticalised' to create harmonies. In this way several sub-scores were generated and some of these were synthesised separately. In some cases these scores were further processed and combined to generate new variants. For example, from one such score a series of seven harmonies was generated, each being a variant of the original pitch series. This series of seven han'noniesoccursfourtimesirtStrirtgsofTokenStrings, using different timbral characteristics each time. As each section of the piece was synthesised, it was transferred from digital tape to multi-track analog tape for later final mixdown." -- Graeme Gerrard