The acoustic and auditory performances of the three Thai level tones

This study offered a preliminary look at the acoustic and auditory performances in an isolated monosyllable environment of the three level tones (i.e. High, Mid and Low tones) in Thai via several relevant acoustic and perception experiments. The results show that Mid tone is the only one which can be accepted as a level tone either in production or in perception and Low tone has two main variants: low-level tone and low-falling tone. But it is quite questionable to continue to take High tone as a level tone because “level” as a sound feature cannot be pronounced and identified as a typical feature of High tone. A High tone is actually a “mid -high-level” tone. Also, the movement of contour is very important when perceiving High tone.