Studies of Nasal Consonants with an Articulatory Speech Synthesizer

An electrical analog of the nasal cavities has been designed for use in conjunction with a dynamically controllable analog of the vocal tract [G. Rosen, J. Acoust. Soc. Am. 30, 201 (1958)]. The acoustical coupling between vocal tract and nasal cavities is electronically variable. Listening tests are conducted to determine the most suitable vocal-tract configurations for producing nasal consonants in consonant-vowel and vowel-consonant syllables. Other listening tests determine the most suitable patterns of temporal variables for these syllables. In general, it is found that more natural-sounding syllables are obtained when the velopharyngeal coupling varies slowly with time compared to changes in vocal-tract configuration. The results compare favorably with recent cineradiological data, and are interpreted to support the view that studies with articulatory synthesizers reveal important details about the production and perception of natural speech. The experiments demonstrate that speech can be synthesized from articulatory information in a straightforward and natural manner.