Composing with Parameters for Synthetic Instruments

This text and the accompanying composition COALS make up my dissertation for composition at UIUC.


This dissertation presents a theory for designing musical instruments which produce sound by means of computer software, and suggests fruitful ways of composing for such instruments. Unlike other research in new instruments, it focuses on the interfaces between performer, instrument-controller and sound synthesizer. Instead of asking only what sounds a given instrument might produce, it asks how one might perform a given family of software-synthesized sounds, thereby encouraging composition of live music with the rich sound material offered by software synthesis.

After surveying historical practice in explicit composing with parameters and analyzing the parametric behavior of existing orchestral and electronic instruments, a general solution to the problem of controlling an n-parameter synthesizer with fewer than n (two or three) controls is presented. This solution, simplicial interpolation, is compared to previous partial solutions in the literature. Examples and guidelines are given for applying this solution to particular problems of musical instrument control; future extensions are also presented.

This theory is then applied to design a violin-based software-synthesis instrument called the eviolin. Solo and chamber works using this instrument are analyzed, with emphasis on their explicit representation of parameters in compositional decisions.

Dissertation    (pdf, 265 pages)


Here is the full score to COALS, a composition in two movements for flute, clarinet, eviolin, 'cello, trombone, and bass guitar.

Camera obscura     (pdf, 25 pages)
Carta terrae incognitae     (pdf, 88 pages)

Pitch and loudness of the eviolin should approximate that of a conventional violin. Timbre of the eviolin changes as the instrument moves horizontally in a space about one meter square. From the eviolinistís point of view, the spectrum is thin at left and rich at right, dull towards the back and bright at front. Positions in this square are notated in the score as dots in a square: the top left corner of the notated square corresponds to the front left corner of the horizontal square.

The other instruments also have certain requirements. The flute needs a B foot, and the trombone uses a plunger mute. The bass guitar should have both a bridge pickup and a neck pickup, which produce treble and bass tone respectively; either a switch or a "tone pot" knob can be used to select treble, intermediate modo ordinario, or bass tone. The B-flat clarinet and violoncello have no special requirements.

A few remarks are in order for notations for all instruments. Almost every note head has an accidental; exceptions are made for clear cases like tied notes. (Accidentals do, however, remain in force until the next bar line.) The smaller note heads of grace notes should not misleadingly cause them to be automatically played softer than non-grace notes. Flurries of grace notes should not be rushed at the expense of clarity: each note should be heard. Glissandi are notated as diagonal lines. As a rule they should be fast and not emphasized dynamically.

The document "Composing with Parameters for Synthetic Instruments" and the composition "COALS" are both copyright 2001 Camille Goudeseune.