Mapping Japanese alveolar fricative, alveolar affricate, and alveolo-palatal affricate in time-spectral space

Abstract

Previous studies of speech production have approached the acoustic features of fricatives and affricates in the time and spectral domains. To gain an integrated perspective on the consonants, this study examined whether alveolar fricative /s/, alveolar affricate /ʦ/, and alveolo-palatal affricate /ʨ/ can be mapped in a single time-spectral space. The time-domain variables were the rise duration and the sum of steady and decay duration of the consonants. The spectral-domain variable was the mean intensity of the consonants obtained with a one-third-octave bandpass filter with a center frequency of 3,150 Hz. Using these variables, canonical discriminant analysis was performed for /s/, /ʦ/, and /ʨ/ pronounced by a native Japanese speaker. The results showed that /s/, /ʦ/, and /ʨ/ were successfully mapped in the time-spectral space with high discriminant ratio. This means that the Japanese fricative and affricates having different acoustic features can be integrated into a single representation of the time-spectral domain with a good separation.