Blend in Singing Ensemble Performance: : Vibrato Production in a Vocal Quartet

Objective ‘Blend’ is a defining characteristic of good vocal ensemble performance, and in order to achieve this directors often identify vibrato as a feature to be controlled and consequently restrict its use. Analysis of individual voices in ensemble situations presents several challenges, including the isolation of voices for analysis from recordings. This study considers vibrato production as a feature that contributes to blend through an ecological study of a vocal quartet. Method / Design An SATB vocal quartet was recorded using head-worn DPAs (miniature microphones) and electrolaryngograph electrodes to enable fundamental frequency analysis of the individual voices. The same four-part material was recorded over several weeks of rehearsal to allow analysis of conscious and subconscious changes to vibrato production over time. Alongside the recording of their rehearsal discussions, singers were also asked for opinions of vibrato production in connection with blend. Results / Conclusions The results indicate that the singers in this study adjusted their vibrato to some extent to improve blend, with some instances of synchrony between voice parts. Some conscious alterations to vibrato were made to improve blend, however these are not always evident in the data, suggesting that these singers’ own perceptions of their performance may have be influenced by other factors. These findings indicate a need for further studies of vibrato as a feature of blend, particularly in terms of the synergies between expectation and actual production, and potential synchronicity between singers: increased understanding of vibrato in an ensemble setting will lead to more efficient rehearsal techniques and vocal training, and could prevent vocal misuse leading to pathology in the future.