Abstract:
This study aims at investigating whether rhythmic units influence tonal realizations in Thai connected speech. The informants in this study are three 26 to 30-year-old radio announcers. Their speech is recorded prior to informing them about this study. They are then asked to read 2 sets of tone checklist. The data are first analysed auditorily to indentify rhythmic units, salient syllables, and weak syllables. For each tone, five tokens are selected for each of the following contexts: salient syllable in one-syllable rhythmic unit, salient syllable in two-syllable rhythmic unit, salient syllable in three-syllable rhythmic unit, weak syllable in two-syllable rhythmic unit, the first weak syllable in three-syllable rhythmic unit, and the second weak syllable in three-syllable rhythmic unit. The fundamental frequency value of all of the tokens are analysed and recorded using WINCECIL and EXCEL. Line graphs are drawn. Tonal realizations in the different contexts are analysed statistically using WINPSY 0602 2000(School of Psychology, University of New South Wales). In the presentation of result, the five standard Thai tones are divided into two groups: level tones (mid, low, and high) and contour tones (falling and rising). The study finds that in the case of salient syllables, rhythmic units significantly influence the tonal realizations of contour tones in most contexts, but they do not have the same effect on level tones. In the case of weak syllables, rhythmic units significantly influence tonal realizations in either level or contour tones. However, there are a few interesting exceptions in both salient an dweak syllables. Tonal realizations of the high tone in short checked syllables differ significantly when ocurring in two-and three-syllable rhythmic units. The falling tone differs markedly from the rising tone. While the rhythmic units significantly influence the variation of the falling tone in unchecked syllables in most contexts, they have much less influence on the rising tone.