Context effects on the acoustic realization of stops and affricates in Northern Pwo Karen

Abstract

Studies have shown that the voice onset time (VOT) of alveolo-palatal affricates is the longest, followed by velars, dental/alveolars, and bilabials. In a reciprocal pattern, closure duration is the longest for bilabials, followed by dental/alveolars, and then velars. Longer VOT is also associated with high and front vowels and tones with rising components. Moreover, the VOT of voiceless unaspirated stops is reported to be longer and closure duration shorter in nasal words. Finally, the voiceless interval has been described as constant in some languages and inconstant in others. Given the evidence of previous research, this study investigates the effects of place, nasality, tone, and vowel quality on the VOT, closure duration, and voiceless interval of the voiced and voiceless obstruents of Northern Pwo Karen (N. Pwo), a language of Thailand. N. Pwo (ISO 639-3 pww) is a ‘true voicing’ language with a three-way distinction in stops, voiceless aspirated and unaspirated affricates, oral and nasal vowels, and six tones (four modal tones and two glottalized tones). In N. Pwo, the place effects on VOT and closure duration pattern reciprocally. Whereas, both VOT and the voiceless interval are longer before oral vowels compared to nasal vowels. VOT is longest before the mid tone, which has a slight rise, while it is the shortest before the falling-glottalized tone. This pattern is reversed for the closure duration of aspirates and voiced stops. Finally, VOT, closure duration, and the voiceless interval are the longest before high and front vowels.