The Application of Tone-Clock Theory to Contemporary Jazz Composition - ISJAC 2024

International Society of Jazz Composers and Arrangers (ISJAC)
International Jazz Composers' Symposium 2024:
Paper Presentation:
The Application of Tone-Clock Theory to Contemporary Jazz Composition
by Jonathan Lindhorst
Abstract:
Despite jazz’s unique ability to engage with and assimilate diverse influences from across the world, it has largely resisted adopting aspects of atonal or twelve-tone music, especially in an improvised context. However, in recent years, some jazz improvisers have begun to develop a post-tonal approach to improvisation using Tone-Clock Theory (TCT), a harmonic system and chromatic “map” that is free of the restrictions typically associated with serial or twelve-tone music. Codified in 1982 by Dutch composer Peter Schat and later vastly expanded by New Zealand composer Jenny McLeod, TCT identifies twelve “chromatic tonalities” derived from the twelve possible atonal triads (Allen Forte’s trichordal set classes), which are labelled as “Hours” and organized around a circular clock face. Using a transpositional operation called ‘steering,’ these triadic sets can then be expanded to assemble a non-repeating twelve-tone harmonic field based on its interval-class, each with its own distinct ‘harmonic flavour.’
In my paper, I will give a brief explanation of the foundational principles of TCT and, drawing from the compositional concepts of Schat and McLeod, demonstrate a few ways that I have adapted Tone-Clock Theory into my own creative practice as an improvising composer, showing how twelve-tone and atonal concepts can be used freely and musically in contemporary jazz.
Presented on May 18th, 2024, at the Blair School of Music, Vanderbilt University, Nashville, Tennessee.
This presentation was made possible by the generous support of:
The Schulich School of Music, McGill University
The Centre for Interdisciplinary Research in Media and Technology (CIRMMT)
We Acknowledge the support of the Canada Council for the Arts.
www.jonathanlindhorst.com

[@mil3ston3s]

I'm not totally clear on how you select your sequence in steering-for instance, some have repetition (1+3/3+1 followed by 1+3/3+1) and others seem mirrored (1+3/1+3 before 3+1/3+1)-does it matter which pattern you select as long as all the following sets are derived in one particular way?

[@jonathanlindhorst6072]

Hey there! I assume you're speaking about the makeup of a complete steering of a chromatic tonality with all twelve non-repeated pitch-classes? The short answer is that the patterns are predetermined and that one simply has to memorise which ones go with which steerings. In asymmetrical hours, there needs to be an equal mixing of minor and major triads, resulting in only four permutations that are ever used: MMmm, mmMM, MmMm, mMmM.
Hour III (1+3) has 3 potential steerings, hours Vm4 (1+5+1), VIIm4 (2+3+2) and IX4 (5+5+5), though the last two are really just the same thing. III/Vm4 uses MmMm pattern and has 6 transpositions, III/VIIm4 is mmMM and has 12 transpositions, and III/IX4 is mMmM and also has 12 transpositions. As I said, I have yet to detect any specific pattern that carries over across tonalities, but memorisation isn't that difficult. I've been using flash cards. I hope that answers your question.