Which "physics" is the human voice subject to? How are perceived sound qualities and identities interrelated with physical properties? What do these interrelations tell us about voice, speech, and singing?
Relationship between fundamental perceptual features of the voice in speech and singing and their observable physical characteristics.
Lack of a phenomenological description documenting the possible extent of variation in vocal utterances.
Characteristics of voice, characteristics of vowels.
Comparison of trained stage voices with untrained voices.
Investigation of the parallelism between perception and acoustic characteristics.