[Publication also available in French — Vous avez dit acousmatique? — Traité de composition acousmatique.]

Of this work, its ambition and its scope, Magritte would have said: “This is not…” (… a treatise, an encyclopaedia, an anthology…). And to describe its richness, if I were to allow myself a playful comparison, I would borrow this image, full of promise, from Olivier Messiaen: A “jumble of rainbows”! This means that as one reads and examines so many works, so many authors cited, so many “scenarios” and diverse approaches — all judiciously selected, gathered and arranged here — new avenues of listening will open up. New horizons. And there will be many inventive resonances. The main task remains — one that will depend on the reader’s own passionate enthusiasm. And my advice will simply be that of Debussy: “Find your own fingerings…”

— François Bayle