A composer’s imagination reaches beyond ‘realistic’ physical laws, and aims at illusory, groundbreaking sound creations and sensations.
An illusory sound process (‘trompe l’oreille’ effect, literally, ear-deceiving) can be created by breaking apart the unambiguous coherence between different musical parameters (pitch, duration, timbre, dynamic, etc.), and, consequently, rendering it diffuse, asynchronous, ambiguous, indistinct.
This publication explains 'acoustic illusion' as a phenomenon and focuses on a number of experiments of the past decades. It further comments on examples from the composition practice and music literature, and suggests — through ‘hands-on’ templates — a number of strategies pertaining the use of acoustic illusion in contemporary composition.