Vibrato rate variability in three professional singing styles: Opera, rock, and Brazilian country

Abstract

Vibrato is one of the most expressive aesthetic characteristics of singing voice. Indicative of good voice quality is typical of lyrical singing but it is also found in others styles of popular music. Acoustically, vibrato is defined as a long-term periodic modulation of the fundamental frequency. It occurs as a result of the laryngeal muscular system and is comprised of three main parameters: rate, extent, and amplitude variation. The main controversy refers to the physiological mechanism of vibrato production, specifically concerning its neurological conscious control, as well as the intra-subject variability of its acoustic parameters. In this study, we compare the characteristics related to vibrato rate (VR), assessing 423 emissions, from recorded samples, produced by 15 professional singers, publicly and artistically acclaimed in occidental culture, to represent three music styles: opera, rock and Brazilian country (sertanejo). We analyzed the samples through GRAM 5.01 and found that the VR was kept constant intra-subject, independently of the singing style. The mean values for the VR for opera and Brazilian country singers were higher than for rock singers. Effects of vocal training, kinship and aging on the vibrato rate, as well as technical skills to control it are objects of our future studies.