Deriving speaking rate effects on tonal realization without varying the speech rate

Abstract

Previous research investigates the effect of durational variation on tonal realization by artificially inducing a change in speaking rate. Through an investigation of the f0 pattern of Cantonese mid-rising tone, this paper introduces a novel, indirect, method of investigating durational effect on tonal realization by looking at the variation in tonal realization in different syllable types. Cantonese has three syllable types: CV, CV(V)O, CV(V)N. CV(V)N syllables are found to be significantly longer than CV syllables, which in turn are significantly longer than CV(V)O syllables. In this study, five native Cantonese speakers were asked to recite a list of Cantonese words with a mid-rising tone in a carrier phrase. The f0 of the Turning Point (the lowest point of a rise), the f0 peak of the rise, the durations of the Turning Point and the f0 peak relative to the onset of voicing, and the duration of the syllable rime were measured. The results show that the f0 peak frequency remains constant regardless of the duration of the syllable. The f0 of the Turning Point gets higher when the duration of the syllable becomes shorter. Finally, the slope of the f0 rise remains constant regardless of the duration of the syllable.