The standard vocal repertoire for soprano requires use of the uppermost segment of the female voice, which is typically produced using whistle register phonation. Voice teachers recognize that sopranos use whistle register phonation during performance to produce pitches in the highest segment of their range; however, the use of whistle register phonation as a training tool for female singers of all voice types is less common and the benefits of using whistle registration exercises to condition the female voice are not widely known. While several pedagogical manuals recommend vocal exercises that use whistle register phonation in the range of the second passaggio and in the highest segment of the female voice, no research has been conducted to investigate the benefits of singing in whistle register.
The purpose of this study was to measure the efficacy of vocal exercises that incorporate whistle register phonation as treatment for poor intonation and pressed and/or breathy vocal quality in female singers with vocal challenges in the second passaggio of their voice. The influence of whistle register phonation on extending vocal range was also investigated.
A treatment-no treatment (ABAB) research design was used. Five female vocalists attended 16 weekly sessions. During the treatment phases, participants received weekly instruction in vocal exercises using whistle register phonation and practiced these activities daily. Audio samples of two vocal exercises and a repertoire excerpt were collected weekly. Measurements taken during the treatment phases were compared to measurements taken during the no-treatment phases.
Results of comparative Voice Range Profiles and a weekly Range Extension Measurement Task showed a positive relationship between practice of whistle register exercises and an increase in the upper pitch range in all subjects. Subjects gained an average of 2.4 semitones during Treatment Phase 1, when the whistle register tasks were introduced. Subjects lost an average of 1.2 semitones during the No Treatment phase, when the practice of whistle register tasks was withdrawn. Subjects gained an average of 2.2 semitones during Treatment Phase 2, when the whistle register tasks were reintroduced. The average overall gain in the upper pitch range was +4.3 semitones for mezzo-sopranos and +2 semitones for sopranos. In addition, data collected to measure the pitch range over which whistle register phonation was possible showed an average range of 14 semitones (D5 - E6); supporting the notion that whistle register phonation is possible in the range of the second passaggio and could be developed in this range by female singers of all voice types.
Eight voice teachers rated each audio sample for intonation and vocal quality during register transition through the second passaggio. Mixed-model ANOVA (analysis of variance) was conducted to compare the effect of whistle register phonation exercises on quality of intonation, vocal quality, the presence and severity of breathiness, and the presence and severity of strain at each phase of the study. Significance was determined at the p<.05 level.
There was a significant effect of whistle register phonation exercises on severity of Breathiness [F(3,209) = 6.66, p = 0.0003]. Mean severity ratings for Breathiness for all subjects were significantly lower during No Treatment than in Treatment Phase 1 and Treatment Phase 2, suggesting that breathiness was less severe when the subjects were not practicing whistle register exercises.
Severity of strain generally decreased continually throughout all phases. Mean severity ratings for Strain were consistently lower for Treatment Phase 1, No Treatment, and Treatment Phase 2 compared to Baseline. The differences between Treatment Phase 1, No Treatment, and Treatment Phase 2 were statistically significant [F(3,209) = 3.52, p = 0.0161]. Mean Intonation ratings generally increased through Treatment Phase 1 and were significantly higher for the No Treatment phase and Treatment Phase 2 compared to Baseline [F(3,209) = 2.99, p = 0.0322]. The effect of whistle register phonation exercises on vocal quality was not significant at the p<.05 level.
A Pearson Correlation Coefficient (PCC) was used to calculate the intra-judge reliability for perceptual evaluation of all vocal tasks. Statistical analysis comparing the judges' ratings for identical audio samples shows that in this study the judges were consistent in their rating of Breathiness (PCC = 0.76) and had difficulty rating Strain (0.57), Vocal Quality (0.60), and Intonation (0.65). A PCC was used to calculate the correlations between each pair of judges' rating for all vocal tasks, and Cronbach's Alpha was used as an overall measure of the inter-rater reliability. Statistical analysis comparing the judges' ratings for all audio samples shows that in this study the judges were consistent in their rating of Breathiness (α = 0.80), mediocre in rating Strain (0.62) and Vocal Quality (0.69), and not consistent in their rating of Intonation (0.53).
The results of the current study suggest that whistle register exercises can be used to facilitate range extension for all female voice types. That performance of whistle register phonation exercises correlated to increased breathiness implies that the exercises tested in this study may not be an effective treatment for singers with breathy voices. Further research investigating the influence of whistle register exercises on intonation, overall vocal quality, and severity of strain is needed. Results of the intra- and inter-rater reliability tests demonstrate a need for research that explores more reliable ways to quantify perceptual evaluation of vocal quality in singers.
| Identifer | oai:union.ndltd.org:uiowa.edu/oai:ir.uiowa.edu:etd-4898 |
| Date | 01 July 2013 |
| Creators | Holmes-Bendixen, Allison Ruth |
| Contributors | Finnegan, Eileen M., Joselson, Rachel |
| Publisher | University of Iowa |
| Source Sets | University of Iowa |
| Language | English |
| Detected Language | English |
| Type | dissertation |
| Format | application/pdf |
| Source | Theses and Dissertations |
| Rights | Copyright 2013 Allison Ruth Holmes-Bendixen |
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