viola and electronic resonators

First piece of Grisey’s cycle Les espaces acoustiques, Prologue demonstrates the nature of spectral composition with almost didactic clarity. For solo viola, this piece is cyclic in form and built around repetition with variations. Each variation is an expansion of the one before, creating a musical spiral. The opening phrase, repeated several times, introduces the key elements of the work: a grouping of five pitches set against an aperiodic, low B – played on the viola’s lowest string tuned down a semitone. Together, these six pitches suggest the harmonic spectrum in the overtone series over low a E, a note that is in fact never explicitly heard. The six projected pitches constitute the third, fourth, fifth, sixth, seventh and ninth harmonics of this “silent fundamental.” There are two versions of this work: one for solo viola, and one for viola plus live electronic resonators, which colour the sound in a way similar to the seven sympathetic strings of the viola d’amore. This older instrument, popular in the Baroque, fell out of favour, as Grisey suggested, due to excessive polyphony. Nevertheless, since the texture of Prologue is monodic as opposed to polyphonic, “there is no reason not to reinvent sympathetic strings” said Grisey.