This research aims to analyze and compare the acoustic characteristics of the tones in the Yong language, as spoken by three generations in Pa Bong Luang Village, Chiang Rai Province, Thailand. Nine female Yong speakers were divided into three groups; over 60 years old, 35-50 years old, and under 25 years old. A wordlist of Yong tones was recorded directly on to a computer. The fundamental frequencies were measured using Praat and then converted into semitones. The results showed that there are six tones in Yong, namely mid-rising tone, mid tone, low tone, high tone, mid-falling tone, and high-falling tone. The acoustic characteristics of the Yong tones that are spoken by three generations suggested that Yong tones are changing. The variations were found in the high tone. In the over-60 group, the high tone started at a high pitch and then fell sharply to a low pitch, whereas in the 30-50 group, the high tone began at a high pitch and fell sharply to a low pitch with a contour similar to the high-falling tone. In the under-25 group, the high tone had a high falling contour like the high-falling tone, and it also merged with the mid-falling tone. The variations and changes appear to be caused by language contact with Tai Yuan and Standard Thai, the majority language in Chiang Rai province, and the majority and official language in Thailand, respectively.
Tone, variation, yong, language contact