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.

研究表明，牙槽腭塞塞音的发声时间（VOT）最长，其次是软颚音、牙/牙槽音和双唇。在倒数模式中，双唇闭合持续时间最长，其次是牙齿/牙槽，然后是软颚。更长的 VOT 还与高元音和前元音以及带有上升成分的音调有关。此外，据报道，清音不送气塞音的 VOT 更长，鼻音闭合持续时间更短。最后，清音间隔在某些语言中被描述为恒定而在其他语言中被描述为不稳定。鉴于先前研究的证据，本研究调查了地点、鼻音、音调和元音质量对北普沃克伦语（N. Pwo）的浊音和清音阻塞的 VOT、闭合持续时间和清音间隔的影响，一种语言泰国的。N。Pwo (ISO 639-3 pww) 是一种“真正的发声”语言，在塞音、清送气和不送气塞擦音、口元音和鼻元音以及六个声调（四个情态声调和两个声门声调）中具有三向区别。在 N. Pwo 中，地点对 VOT 和关闭持续时间模式的影响是相互的。然而，与鼻元音相比，口元音之前的 VOT 和清音间隔都更长。VOT在中音前最长，略有上升，而在降声门前最短。对于吸气和浊音停止的关闭持续时间，这种模式是相反的。最后，VOT、闭合持续时间和清音间隔在高元音和前元音之前最长。口元音和鼻元音，以及六个声调（四个情态声调和两个声门声调）。在 N. Pwo 中，地点对 VOT 和关闭持续时间模式的影响是相互的。然而，与鼻元音相比，口元音之前的 VOT 和清音间隔都更长。VOT在中音前最长，略有上升，而在降声门前最短。对于吸气和浊音停止的关闭持续时间，这种模式是相反的。最后，VOT、闭合持续时间和清音间隔在高元音和前元音之前最长。口元音和鼻元音，以及六个声调（四个情态声调和两个声门声调）。在 N. Pwo 中，地点对 VOT 和关闭持续时间模式的影响是相互的。然而，与鼻元音相比，口元音之前的 VOT 和清音间隔都更长。VOT在中音前最长，略有上升，而在降声门前最短。对于吸气和浊音停止的关闭持续时间，这种模式是相反的。最后，VOT、闭合持续时间和清音间隔在高元音和前元音之前最长。有轻微的上升，而在降声门音之前最短。对于吸气和浊音停止的关闭持续时间，这种模式是相反的。最后，VOT、闭合持续时间和清音间隔在高元音和前元音之前最长。有轻微的上升，而在降声门音之前最短。对于吸气和浊音停止的关闭持续时间，这种模式是相反的。最后，VOT、闭合持续时间和清音间隔在高元音和前元音之前最长。