flute, clarinet, trombone, violin, viola, cello and double bass

Gérard Grisey’s Les espaces acoustiques is one of the seminal works of the spectral music school. “Everything began with Périodes,” said Grisey in an interview with Guy Lelong. “From a formal point of view, this piece consists of a succession of episodes, in the last of which I experimented for the first time with a technique the seemed to me in need of development. I had analyzed, with the help of a spectrogram, the sound of the trombone’s E and created its main components (the fundamental and its harmonics) with the instruments of Périodes. That opened my eyes to a new way of harmonic thinking and which I later called “instrumental synthesis.” I then had to write a sequel, and this turned out to be Partiels for 18 musicians (1975) which includes the instruments of Périodes. Then I finally decided to compose a whole cycle that would begin with a piece for solo instrument and finish with a large orchestra. As the viola played a prominent role in Périodes, the solo piece had to be written for this instrument, and it was Prologue for solo viola.”

There are three kinds of moments in Périodes, analogous to human breathing: states of inhaling, exhaling and resting are translated aurally into moments of dynamic and growing tension, dynamic and progressive relaxation, and static periodicity. The periodicity of the piece creates a distinct weight, as it turns in on itself in repetitive circles, until a new germ surfaces and spurs on a new energy and the evolution of a new thread. The cyclic nature of Périodes is not meant to affect synthetic accuracy. Instead, the cycles are more organic, or “blurred” like our own heartbeats, like our own walking paces, rhythmic but with a degree of human fluctuation.