Auditory illusion

An auditory illusion is an illusion of hearing, the aural equivalent of an optical illusion: the listener hears either sounds which are not present in the stimulus, or "impossible" sounds. In short, auditory illusions highlight areas where the human ear and brain, as organic, makeshift tools, differ from perfect audio receptors (for better or for worse).

Examples of auditory illusions:

According to Purwins, auditory illusions have been used effectively by various composers, e.g. Beethoven (Leonore), Berg (Wozzek), Krenek (Spiritus Intelligentiae Sanctus), Ligeti (Piano etudes, Violin Concerto, Doppelkonzert für Flöte, Oboe und Orchester), Honegger (Pazific), Stahnke (Partota), Reutter (The Shephard’s Flute from Orchestral Set No. 1).

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