Acoustic analyses of trained singers perceptually identified from speaking samples

This study investigated selected acoustic cues in the speaking voices of five professional singers; cues that may have enabled naïve listeners to differentiate them from nonsingers and other trained singers who were not consistently identified from their speaking voices. Subjects were divided into three groups based on listeners' perceptual judgments. Group I, the identified singers, consisted of five professional singers, three males and two females, with an average identification score, from their speaking utterances, of 79%. Group II, the unidentified singers, consisted of 15 trained singers, seven males and eight females, who, as a group, were identified correctly from their speaking utterances only 52% of the time. Group III consisted of 20 nonsingers who were incorrectly identified from their speaking utterances as singers only 36% of the time, that is, they were correctly identified as nonsingers from their speech 64% of the time. Acoustic parameters chosen for measurement from vowel productions were: (1) percent jitter, (2) percent shimmer, and (3) noise-to-harmonic ratio. The second sentence of the "Rainbow Passage" was selected to compare several frequency and duration measures between the three groups. These were: (1) mean speaking fundamental frequency, (2) standard deviation of the fundamental frequency, (3) sentence duration, (4) word duration, and (5) consonant/vowel ratio. The data indicated that the acoustic parameters that most consistently distinguished the identified singers from the unidentified singers and the nonsingers were fundamental frequency variation and durational differences. The identified singers varied their speaking fundamental frequency significantly more than did both the unidentified singers and the nonsingers. The identified singers also had longer vocalic segments than did the others.