This work is part of the musical cycle Espaces acoustiques, consisting of Prologue for solo viola, Périodes for seven musicians, Partiels for 16 or 18 musicians, Modulations for 33 musicians, Transitoires, and Épilogue for great orchestra.
The title should be read as “a part” of a greater whole, but also in the acoustic sense as partials.
The sound of the piece is mostly determined by two elements: periodicity and the spectrum of partials. These easily recognisable elements unify the musical discourse and are responsible for its dynamic qualities. The discourse itself clearly draws on the cyclic form, but also on the shape of the human breath: inhaling—exhaling—rest, in other words: tension— movement—release— retrieved energy.
Many sections of Partiels are based on a new technique of instrumental synthesis. This technique is similar to additive synthesis applied in the processing of electronic and digital music. It uses an instrument to produce the various sound partials (microsynthesis) and the global sound form (macrosynthesis). The technique results in blurring the qualities of the individual (instrumental) sources of sound until a newly invented, synthetic sound is produced. The various fusions make it possible to articulate and organise a wide range of sounds, from harmonic spectrum to white noise, passing through various nonharmonic partial spectra.

Gérard Grisey