Durational Contrast and Centralization of Vowels in Hindi and Thai

A number of languages have short vowels using smaller acoustic space, hence more centralized, as compared to long vowels which are also known to be peripheral vowels using a larger acoustic space. Such a phenomenon is attested in Hindi, English and several other languages including Japanese and Korean. This is a spectrographic study of all the 18 vowels of Thai in comparison with all the ten vowels of Hindi. The present study uses the first two formants of the vowels to arrive at a graphic representation of the acoustic space for long and short vowels in the two languages under study. The area is calculated using Irregular Polygon Area Calculator. The comparison of the acoustic space used by the long and short vowels in the two languages shows interesting results which are presented in this paper.