'Voice' separation: theoretical, perceptual and computational perspectives

The notions of ‘voice’, as well as, homophony and polyphony, are thought to be well understood by musicians. Listeners are thought to be capable of perceiving multiple ‘voices’ in music. However, there exists no systematic theory that describes how ‘voices’ can be identified, especially, when polyphonic and homophonic elements are mixed together. The paper presents different views of what ‘voice’ means and how the problem of voice separation can be described systematically, with a view to understanding the problem better and developing a systematic perceptually-based description of the cognitive task of segregating ‘voices’ in music. Vague (or even contradicting) treatments of this issue will be presented. Elements of a systematic theory that can be implemented as a computer program are also proposed.