COEFFICIENT: Frictional Percussion and Electronics (1991)

Dialects is produced through the process of electronically transforming both vowel-like and fricative sound sources into each other, in two interactive streams.

The first source is the beating of insects' wings; the second, alpha waves, modulated in both frequency and amplitude. Both sources were produced originally in laboratories, and subsequently subjected to various transformations by the composer. The principal devices used to produce the transformations are (1), a percussively triggered vocoder, and (2), a percussion generator with pitch-modulation capability.

A performance of Dialects combines groups of these sounds, previously prepared, rotating at rapid speeds (upto 30 times per second), with live electronic-percussive elements, similarly rotating. Two percussion generators are used, each triggered by bunches of vibrating wire flowers, made for this work by the artist, Jackie Monnier. The combined rotations are deployed and presented through an eight-channel sound system.

Some of the prepared sound materials were produced for an earlier work (Likeness to Voices/Dialects), which was realized at the Centre Européen pour la Recherche Musicale, Metz, on a commission from the Calouste Gulbenkian Foundation (1982).

-David Tudor