Discrimination of Japanese fricatives and affricates by production boundaries in time and spectral domains: A case study of a female native speaker

Abstract

Acoustic features of fricatives (/s/ and /C/) and affricates (/ ¶/ and /tC/) spoken by a female native speaker of Japanese were investigated. Discriminant analysis in the time domain revealed that fricatives (/s/ and /C/) and affricates (/ ¶/ and /tC/) are well separated at a discriminant ratio of 98.0% (n ¼ 508) when using the variables of the rise duration and the sum of steady and decay durations of the consonants' intensity envelope. Discriminant analysis in the spectral domain revealed that alveolar consonants (/s/ and / ¶/) and alveolo-palatal consonants (/C/ and /tC/) are well separated at a discriminant ratio of 99.2% (n ¼ 508) when using the variable of the mean intensity of one-thirdoctave bandpass filter with a center frequency of 3,150 Hz. In addition, the four consonants were correctly identified at an accuracy rate of 97.2% (n ¼ 508) when using a combination of production boundaries obtained in the above two discriminant analyses. Results suggest that the acoustic features of the four consonants can be represented by the time-and spectral-domain variables described above.

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

“…However, the results may be extended to distinguish /C/ from /s/, / ¶/, and /tC/. Previous studies suggested that consonants with different manners of articulation (i.e., fricative vs. affricate) can be discriminated by the time domain variables [e.g., 1, 2, 11, 16], whereas consonants with different places of articulation (i.e., alveolar vs. alveolo-palatal) can be discriminated by the spectral domain variables [e.g., 3,4,12,16]. Therefore, the alveolo-palatal fricative /C/ would be distinguished from the alveolo-palatal affricate /tC/ in the time domain, and from the alveolar fricative /s/ in the spectral domain.…”