Subjective ratings of sentences in clear and conventional speech
To determine the feasibility of using subjective ratings of clarity to identify perceptual differences between clear and conversational speech and among different talkers, sentences produced by 8 talkers selected from the Ferguson Clear Speech Database (Ferguson, 2004) were presented to listeners with normal hearing. Listeners rated the clarity of each sentence on a scale of 1 to 7 (1 = lowest possible clarity; 7 = highest possible clarity). Clarity ratings were significantly higher for clear than conversational speech and differed significantly among the talkers. Rated clarity was significantly correlated with vowel intelligibility and vowel space measures, but not with speaking rate. The results suggest that subjective clarity ratings are a useful and valid measure of perceptual differences between speaking styles and among talkers..