Interactions of Tone and Intonation in Whispered Mandarin

A previous study has found that whispered Mandarin, though still allowing listeners to perceive tones to a certain degree, does not carry acoustic cues that are special to whispered tones. That conclusion, however, was based on data from only one speaker. The present study attempted to verify the earlier finding with data from more speakers, with an additional goal to find out if there are acoustic cues to intonation in whispered Mandarin and whether they interact with tonal cues. Twelve Mandarin speakers produced tonal as well as intonational contrasts in both phonated and whispered speech. Acoustic analyses found that whispered questions had longer duration, greater intensity and shallower spectral tilt than statements. However, a perception experiment with 20 native listeners showed a strong bias toward hearing statement in whispers, so that questions were identified well below chance. Thus the acoustic properties in whisper were countering each other as cues to intonation. There was also an interaction of tone and intonation in whispers in that Tone 2 and question help each other while Tone 4 and question hinder each other in their perceptual identification. Overall, therefore, there do not seem to be special perceptual cues to whispered intonation either.