The tone system of Ruc and tonogenesis in Vietic languages

Abstract

Rục, a Chứt dialect spoken in the mountainous area of Quảng Bình province, has been described as having four tones characterized by pitch height (F0), pitch contour, phonation types and laryngeal features. In the Summer 2019, I recorded 20 Rục speakers (10 women) reading a wordlist including 66 words made of five vowels /iː, ɛː, uː, ɔː, aː/ in combination with different dental and velar onsets and the four tones. The results show that the four tones in Rục are differentiated by pitch height and pitch contour. Moreover, spectral measures such as H1*-H2*, H1*-A3*, and CPP indicate that the two low-register tones (derived from historically voiced onsets) have a breathy phonation compared to a modal phonation in the two high-register tones (derived from historically voiceless onsets). In words with the two low-register tones, vowels tend to be pronounced with a higher aperture (lower F1) than in the high-register tone context. Besides, syllables ending in the glottal fricative /-h/ have a high level F0 throughout the rhyme, while their phonation types and vowel quality follow the patterns observed in the four tones. These results support (and can be used to fine-tune) theories about tonongenesis and registrogenesis in Vietic languages, Mon-Khmer (Austroasiatic) languages, and languages of Mainland Southeast Asia in general.