The main cue to interrogativity in Dutch declarative questions is found in the final boundary tone. When whispering, a speaker does not produce the most important acoustic information conveying this: the fundamental frequency. In this paper listeners are shown to perceive the difference between whispered declarative questions and statements, though less clearly than in phonated speech. Moreover, possible acoustic correlates conveying whispered question intonation were investigated. The results show that the second formant may convey pitch in whispered speech, and also that first formant and intensity differences exist between high and low boundary tones in both phonated and whispered speech.
Bibliographic reference. Heeren, W. / Heuven, V. J. Van (2009): "Perception and production of boundary tones in whispered dutch", In INTERSPEECH-2009, 2411-2414.