Release mechanisms for stop and nasal consonants

Abstract

Theoretical models have been developed to account for the rapidly changing acoustic events at the release of stop and nasal consonants with different places of articulation. The model for stop consonants predicts the level and spectrum of the initial transient, the burst of noise, aspiration noise, and formant transitions, and shows differences in the contribution of each of these components over the initial 10–20 ms for labial, alveolar, and velar places of articulation. For nasal consonants, the abrupt change in spectrum at the release can be explained by rapid movement of the zeros of the transfer function of the oral-nasal system, and by a somewhat slower movement of the poles. The pattern of movement of the zeros and hence the nature of the spectrum change depend on the consonantal place of articulation. Spectra data for spoken stop and nasal consonants, obtained with fine time resolution, show general agreement with the theoretical predictions, although the lack of quantitative data on dynamic and kinematic articulatory parameters makes detailed comparison difficult. [Work supported in part by a grant from NINCDS.]