What's in a whisper?

Whispering is a common, natural way of reducing speech perceptibility, but whether and how whispering affects consonant identification and the acoustic features presumed important for it in normal speech perception are unknown. In this experiment, untrained listeners identified 18 different whispered initial consonants significantly better than chance in nonsense syllables. The phonetic features of place and manner of articulation and, to a lesser extent, voicing, were correctly identified. Confusion matrix and acoustic analyses indicated preservation of resonance characteristics for place and manner of articulation and suggested the use of burst, aspiration, or frication duration and intensity, and/or first-formant cutback for voicing decisions.