Tone clarity in mixed pitch/phonation-type tones

Abstract In Green Mong, a subset of tones is characterized by phonation type in addition to pitch height, pitch contour and duration, which characterize the remaining tones of the language. This study examines perceptual and acoustic data to address the question of what makes tones clear when tonal identity is determined by this complex of acoustic cues. Native listeners were asked to categorize three tones which have similar falling contours, but which are differentiated by phonation type. Tokens that were correctly identified by 100% of the listeners were compared with tokens that were poorly identified. Perceptually, the breathy and creaky tones are less susceptible to identification errors than the modal tone. Acoustically, the clearest tokens of the three tones are differentiated by details of pitch contour shape, as well as by phonation-type cues. Clear tokens of the creaky and breathy tones are characterized by extreme acoustic cue values which shift these tokens away from space that is occupied by other tones. In contrast, the modal tone essentially occupies the middle ground for the cues examined here: more extreme acoustic values shift the modal tone into acoustic space that is occupied by some other tone in the language.