Abstract:
The aim of this research is to analyze and compare the acoustic characteristics of the formant frequency, duration and intensity of both monopthongs and diphthongs in stressed syllables in Pattani Thai and Bangkok Thai connected speech. The data was collected from 10 respondents; 5 from each dialect. All respondents were asked to have conversation and also answer some questions during the recordings. The data in each dialect consisted of nine short vowels: /I, e, ԑ, ɨ, ә, a, u, o, ɔ/, nine long vowels: /ii, ee, ԑԑ, ɨɨ, әә, aa, uu, oo, ɔɔ/ and three diphthongs: /ia, ɨa, ua/ occurring in closed and open syllables. The total numbers of test tokens were 2,310 (231 x 10 speakers). The acoustic characteristics were analyzed with Praat version 4.4.27 and statically tested by t-test using SPSS version 13.0 for Windows with 0.05 level of significance. The results show that the first formant of both monopthongs and diphthongs in Pattani Thai is lower than that in Bangkok Thai. However, the second formant in Pattani Thai is higher than that in Bangkok Thai. The vowel space of long vowels is more peripheral than that of short vowels. It is noticeable that short vowels are more centralized in both Pattani Thai and Bangkok Thai. Moreover, the variation within the space of each vowel in Pattani Thai is more dispersed than that in Bangkok Thai. The duration of monopthongs in Pattani Thai is shorter than that in Bangkok Thai. The ratio of duration in Pattani Thai for short-to-long vowels in closed syllables is 1:1.95, short-to-long vowels in open syllables is 1:2.50 and long vowels in closed syllables-to-long vowels in open syllables is 1:1.28. The ratio of duration in Bangkok Thai for short-to-long vowels in closed syllables is 1:1.89, short-to-long vowels in open syllables is 1:2.34 and long vowels in closed syllables-to-long vowels in open syllables is 1:1.24. As for diphthongs, the ratio of duration for closed-to-open syllables in Pattani Thai is 1:1.28 while in Bangkok Thai, 1:1.39. Regarding the intensity, the one of short vowels is higher than that of long vowels, and the intensity of diphthongs in open syllables is higher than that in closed syllables in both Pattani Thai and Bangkok Thai. The difference between the intensity of vowels in both dialects is statically insignificant.