Liminal aesthetics : perspectives on harmony and timbre in the music of Olivier Messiaen, Tristan Murail, and Kaija Saariaho.

Harmony and timbre have traditionally been viewed as separate parameters by music scholars and treated as such by composers. Once timbre had been understood scientifically, however, as arising from a fundamental frequency and its overtones sounding at different amplitudes, it became desirable to replicate this structure in music. The composers associated with spectral music, a movement which first emerged in Paris in the 1970s, have enthusiastically explored this closer relationship between harmony and timbre, blurring the distinctions that once existed between these concepts. This thesis examines this new liminal relationship between harmony and timbre, asking how their closer unity has affected the aesthetic decisions made by composers in and around the spectral movement. The thesis takes a perspective which is historical and contextual, tracing this aesthetic shift through representative texts and scores by Olivier Messiaen, Tristan Murail, and Kaija Saariaho