Effects of noise on the discriminability of distinctive features in normal and whisper speech.
William D. Voiers · The Journal of the Acoustical Society of America · 1991
The Diagnostic Rhyme Test (DRT) and Diagnostic Alliteration Test (DALT), a final-consonant counterpart of the DRT, were used to study the effects of band-limited Gaussian noise on normal and whispered speech. Although possibly an artifact of the method of measuring speech-to-noise ratio, whisper speech appeared generally more robust than normal speech over much of the range of conditions involved. In normal speech, and in both final and initial consonants, the features, voicing and nasality are highly resistant to degradation; sibilation and compactness, moderately resistant; graveness and sustention, least resistant. In the case of whispered speech, sibilation and compactness appeared most resistant to noise in both initial and final consonants. In initial consonants, voicing was most affected; nasality, sustention, and compactness, moderately affected. In final consonants, graveness was the feature most affected by noise. These results attest to the robustness of whisper speech and suggest that in some circumstances it could provide a more effective means of communication than normal speech.