Perceptual Measures of Boychoir Voices During the Phases of Pubertal Voice Mutation.

Background/objectives: Vocal changes in the male singing voice associated with puberty are variable and often unpredictable resulting in challenges for the singer and the choral director. Limited knowledge regarding the physiologic changes in the vocal mechanism as they correlate to perceptual variations observed in the male adolescent singer exists in the literature. The purpose of this study was to examine pitch breaks and perceptual characteristics of vocal quality during singing tasks for boys in various stages of the male changing voice.

Study Design: Prospective Study.

Methods: Twenty-eight boys were initially evaluated at Cooksey Stage 0 (Pubertal Unchanged; n = 15) or Cooksey Stage 1 (Mid-Voice; n = 13). Range of age was 8-13 years old. Participants performed vocal slide intervals (1-3-1, 1-5-1, 1-8-1) with discrete starting frequencies on G3, C4, F4, and A4 and sang the "Star-Spangled Banner" in the key of Ab. Pitch breaks and perceptual qualities were evaluated on the recorded tasks by expert raters. Seven boys were evaluated again when they progressed to Cooksey Stage 4 (Baritone) performing the same singing tasks.

Results: For the participants evaluated at Cooksey Stage 0/1, pitch breaks were observed more in the higher frequencies and increased interval spacing regardless of starting frequency. Participants at Cooksey Stage 0 had more pitch breaks than Stage 1. At Cooksey Stage 4, an increase in the number of pitch breaks was observed in comparison to their tasks performed at Stage 0/1 and the perceptual quality of breathiness was significantly greater.

Conclusions: Pitch breaks are a characteristic perceptual change that indicates a young man may be transitioning through puberty. Findings from the present study demonstrate that in addition to perceived pitch breaks, breathiness was noted to significantly increase as the male progressed through puberty. Breathiness was noted to be more significant than vocal timbre and overall vocal quality. This research provides acoustic evidence to enhance the perceptual characteristics of voice change for those who teach and train male voices through puberty.