A study of the acoustic characteristics of consonant, vowel and tone in standard Thai with southern accent in comparision with standard Thai and southern Thai
Abstract:
The objectives of this research are to analyze and compare the acoustic characteristics of consonants, vowels and tones in 1) standard Thai with southern accent (STSA); 2) standard Thai (SDT); and 3) southern Thai (STT). The first and the third groups of informants are the same participants who speak Phatthalung Thai as a mother tongue, they are judged by teachers and friends as STT speakers who pronounce SDT distinct from Bangkok speakers. On the other hand, the second group of informant speaks Bangkok Thai as a mother tongue, they are judged by teachers and friends as SDT speakers who speak correctly. The data was collected from 10 high school students in each group, 5 from each sex. The acoustic characteristics studied in this research are measured from the voice onset time of stop consonants of 1,620 test tokens, the formant frequency and the duration of vowels of 3,690 test tokens and the fundamental frequency of tones of 930 test tokens were analyzed with Praat (Program) and statistically tested with t-Test (p<0.05) According to the research results, it is found that the difference between STSA and SDT is statistically significant as follows: 1) the voice onset time of stop consonants in all manner of articulation; 2) the first and the second formant frequencies in some vowels /ɛ/ /ł/ /ə/ /а/ /ɔ/ /ɛː/ /əː/ /oː/ /ɔː/ and also the duration of some vowels /ə/ /ɛː/ /аː/ /uː/ /ɔː/ ; and 3) the fundamental frequency in all tones. Based on the findings, it can be concluded that the main factors that make of STSA pronunciation distinct from SDT are the voice onset time of stop consonants and the fundamental frequency of the tones. While the minor factors are the formant frequency and duration of the vowels. In addition, some acoustic characteristics of STSA are interfered by STT, as found in the case of mid tone. Also, some acoustic characteristics of STSA have intermediate values between SDT and STT, as in the case of long vowels.