Articulatory-acoustic relations in Cantonese vowel production

The study investigates the quantal nature of two sets of Cantonese point vowels, the long [i: u:] in CV open syllables and the medium-long [i u] in CVS closed syllables, where S = stop consonant, by determining the articulatory-acoustic relations in the production of the four Cantonese point vowels. It evaluates Stevens' quantal theory (1972, 1989) by analyzing variability in articulation and acoustics of the four Cantonese point vowels. It also tests the sensitivity of formant frequencies of these point vowels to variation in linguo-palatal constriction location and degree of constriction along the vocal tract length. The investigation obtains variations in location and degree of linguo-palatal constriction along the vocal tract length during the point vowels, using EMMA AG500, and it relates the articulatory measurements to the corresponding vowel formant frequencies. Preliminary data show that the acoustic consequences of a shift in forward or backward direction of the constriction away from the target position for the point vowels are non-linear. The results appear to support the quantal nature of vowel production (Stevens, 1972, 1989). Furthermore, similar to the findings reported in Beckman, et al. (1995) formant frequencies are relatively less sensitive to variation in constriction location than degree of constriction.