TR-I-0023 :1988.03

桑原尚夫

ホルマント周波数、バンド幅の変形による 声質制御

Abstract:An analysis-synthesis system has been developed which is capable of independent manipulation of acoustic parameters to investigate the contribution of these individual parameters to speech quality. Formant frequencies and their bandwidths were used as the acoustic parameters to characterize the vocal tract configuration, and pitch frequency as the voice source. This paper describes a method how to control the voice quality of natural speech by manipulating the formant frequencies. Formant trajectories extracted from a natural speech were modified to alter their movement to some extent, and the resultant speech wave was synthesized by this method to present to listeners for the judgement of voice quality. It was found that the speech intelligibility or articulateness was improved to some degree when the movement of time-varying formant pattern was slightly emphasized, but too much emphasis would cause degradation of the voice quality.