Document Type


Date of Degree

Spring 2019

Degree Name

MA (Master of Arts)

Degree In


First Advisor

Gompper, David

Second Advisor

Charles, Jean-François

First Committee Member

Cohen Elias, Sivan


“Eclipses” orchestrates the movements of human beings as celestial bodies—as wandering beings that emit waves, cycle in orbit, and create shadows. Subtle microtonal movements, or retunings of the same pitch, tell the story of gradual planetary motion leading to the drama of the eclipse. In the dimmed light of a solar eclipse, even the most familiar surroundings seem unfamiliar and strange.

The harmonic material of “Eclipses” was composed using the Rainbow Harmony Matrix, a MaxMSP-based mouse and keyboard interface designed for real-time interaction with a 2D colorized pitch space defined by Just Intonation ratios. The most difficult coding in this patch was completed thanks to the generous help of Jean-François Charles. The spatialization and color-coding of Just Intonation pitches provided by the Rainbow Harmony Matrix proved invaluable to organizing harmonic and melodic material. Elements of rhythm, timbre, and articulation were largely left to the ear’s intuition.

“Penumbra” magnifies the shadow cast when one celestial body partially obscures the light from another. Moments from “Eclipses” are revisited through a telescopic lens, such that the small whole number relations hiding in the harmonies are magnified, into the field of rhythm. Small gestures orbit each other in wandering motion, building a web of cause and effect.

The harmonic material from “Penumbra” is extracted from two chords occurring in measures 41-43 of “Eclipses.” The small whole number frequency ratios governing the cross-relations of these two chords are magnified and modified to create polyrhythms that cycle over several minutes.


eclipse, intonation, microtonal, penumbra, quartet, string


viii, 20 pages


Includes bibliographical references (page 20).


Eclipses audio file:

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Copyright © 2019 Day McMaster Beyer

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