Acoustic and articulatory variation of Mandarin diphthong /ou/

Abstract

Abstract This study compared dynamic formant trajectories and corresponding ultrasound tongue data of the diphthong /ou/ in Taiwan Mandarin and Beijing Mandarin speakers. Results of the Generalized Additive Mixed Models (GAMM) analyses showed that both groups of speakers produced a clearly diphthongal /ou/, which contrasts with previous auditory-based accounts that /ou/ in Taiwan Mandarin may be monophthongal. The two dialects, however, had rather different phonetic realizations: Taiwan Mandarin had a significantly lower realization for the nucleus of /ou/ than its Beijing counterpart; Taiwan Mandarin also had a significantly more fronted realization for the offglide than Beijing Mandarin. The articulatory patterns mostly corresponded to the acoustic results, in that while tongue dorsum raising was found for all speakers in this study, an additional tongue dorsum fronting gesture was observed for the majority of the Taiwan Mandarin speakers. Together, the results suggest that the less studied dialectal variation in Mandarin vowels may be a promising line of investigation, particularly with parallel acoustic and articulatory data collection.