In Tai Sound Review, I will mainly discuss sound merges across Tai languages. I will use Thai alphabet to represent all Tai languages.
Northern Thai aka Kam Mueang (คำเมือง lit. "city language") is mainly spoken in the Northern region of Thailand.
Common Features (after Tone Split)
- Distinction between r (ร) and l (ล). The former has become /h/.
- Some distinction among ʔj, j, and ɲ (อย, ย, ญ respectively). The j and ɲ merged into /ɲ/, while ʔj became /j/. Thus, there is a distinction between j (อย) and ɲ (ย/ญ).
- Some may pronounce tr (ตร) as k (ก). Thus for these people, there is no distinction between tr and k.
- No distinction between kʰ (ข) and x (ฃ). Both are pronounced as kʰ (ข).
- Distinction between historic g (ค) and ɣ (ฅ). The former is pronounced as /k/ and the latter as /kʰ/.
- No distinction between historic cʰ (ฉ) and s (ส). Both are pronounced as s (ส).
- All consonant clusters are simplified, e.g. kl (กล) becomes k (ก), except stop+w clusters, e.g. kw (กว).
- Historic unaspirated stops + r (which became /h/) merged with aspirated voiceless stops. E.g. pr (ปร) > pʰ (ผ). Thus, there is no distinction between pr and pʰ.
- No distinction between -aj (ไ) and -aɯ (ใ). Both are pronounced as /aj/.
- Historic voiced stops became unaspirated voiceless stops. E.g. *d > t (ท > /ต/). Thus, unlike Thai, there is a distinction between historic d (ท) and dh (ธ). The former is pronounced as /t/ and the latter as /tʰ/.
- s + w is a possible cluster. E.g. สวัสดี is pronounced as swúat.sá.dii Cf. Thai sa.wàt.dii.
- Distinction among six tones. Unlike Thai, tone 3 and tone 5 are pronounced differently, e.g. หญ้า and ย่า are pronounced differently. The former has glottalized high level tone, while the latter has falling tone (Chiang Mai) or mid tone (Naan).