Contribution of Spectral Shapes to Tone Perception

摘要

Tones in tonal languages are defined based on the characteristics of their fundamental frequencies. However, it has been shown that fundamental frequencies alone do not lead to good tone identification, either by human or machines. This paper reports a study based on tone perception experiments in which participants identified Thai tones from recorded mono-syllabic, bi-syllabic, and trisyllabic stimuli as well as their modified counterparts. Stimuli were modified in various aspects so that effects of fundamental frequency, syllable energy envelope, and spectral shape to tone perception could be studied. Results indicate that spectral shape, especially in the vicinity of the first formant, contributes significantly to the participants' ability to correctly identify tones and the contribution is greater with more syllables in the stimuli.