Tuning Timbre Spectrum Scale

Summary

by William A. Sethares Here is a brief guide to Tuning Timbre Spectrum Scale. Click for a quick rundown of the central ideas or for an overview, go to the complete table of contents by clicking on the appropriate chapter, or click to download the full book. The book includes a set of sound examples on CD, and the full text of one of the early seminal articles is now available on-line. Several pieces of music that exploit the sound techniques are also available for download in mp3 format. The Octave is Dead... Long Live the Octave Introducing a dissonant octave--almost any interval can be made consonant or dissonant by proper choice of timbre. Some basic ideas from psychoacoustics are required to understand the interaction between timbre (or spectrum) and sensory consonance and dissonance. Pairs of sine waves interact to produce interference, beating, roughness, and the simplest setting in which (sensory) dissonance occurs. Many scales have been used throughout the centuries. The words `consonance' and `dissonance' have had many meanings. Tuning Timbre Spectrum Scale focuses primarily on sensory consonance and dissonance. The relationship between spectra and tunings is made precise using dissonance curves. See also the paper Relating Tuning and Timbre. Three concrete examples demonstrate the usefulnes of related scales and spectra in musical composition. Adaptive tunings modify the pitches of notes as the music evolves in response to the intervals played and the spectra of the sounds employed. You can hear adaptive tuning at work by downloading the piece Three Ears, which is available in mp3 format. Adaptation: tools for retuning, techniques for composition, strategies for listening. In the same way that Western harmonic instruments are related to Western scales, so the nonharmonic spectrum of gamelan instruments are related to the gamelan scales. The dissonance score demonstrates how sensory consonance and dissonance change over the course of a musical performance. ...