Articulatory-acoustic relations in Cantonese vowel production

The study evaluates the quantal theory (Stevens, 1972, 1989) through investigating the articulatory-acoustic relations in two sets of Cantonese point vowels, the long [i: u:] and the medium-long [i u]. It determines the sensitivity of vowel formant frequencies to variations in linguo-palatal constriction location and constriction size along the vocal tract length. The articulatory and acoustic data on the vowels obtained in this study show non-linear relations between the acoustic consequences and the up-down and front-back displacements in linguo-palatal constriction, as what the quantal theory predicts. Moderate displacements in constriction location and constriction size bring about large perturbation in acoustic parameter. The level of sensitivity of formant frequencies to variation in tongue displacement is lower in [i: u:] than [i u], suggesting that the quantal nature is more apparent in [i: u:] than [i u]. For the Cantonese point vowels, F1 is more sensitive to variation in constriction location than constriction size, whereas F2 is more sensitive to variation in constriction size than constriction location. A difference between Cantonese and English is that, in English, both F1 and F2 are relatively more sensitive to variation in constriction size than constriction location. © 2012 Acoustical Society of America.