Articulatory-Acoustic Relationships in Fricative Consonants

Abstract

The v^rork described in this paper is concerned with improving fricative models by investigating the acoustic mechanisms involved in their production more closely. Previous studies reviewed fall into four categories: general aeroacoustics, mechanical models of speech, analysis of speech, and theoretical models, including synthesis. The work reported here combines these various approaches. Three levels of experiments with mechanical models of increasing realism are described. As a result, two source mechanisms are identified: the obstacle source, in which sound is generated at an abrupt obstacle to the airflow, such as the teeth, downstream of the constriction, corresponding to /s, //; and the wall source, in which sound is generated by striking a wall at an oblique angle to the flow, corresponding to /f, x/. Source spectra differ, and are given in each case. Comparison to speech data from which the models were derived supports and extends the conclusions.