Introduction: This study aimed to define and then compare two sets of vocal quality terms commonly implemented by singing professionals, Front – Back and Light – Dark, using acoustic, aerodynamic, and perceptual measurements, as well as a survey asking voice professionals to rate and define them. Methods: Voice samples from members of university singing groups were collected and analysed. Voice professionals then rated segments of the recordings from Front to Back or Light to Dark to determine inter-rater agreement and the degree of perceptual overlap between them. Listeners also described how they define these terms. Statistical tests with post hoc tests and discriminant function analysis (DFA) were conducted to determine if acoustic, aerodynamic and formant measures could differentiate between the voices. Results: The F1 and F2 values for Light/Front were significantly different from those for Dark/Back; however, post hoc analyses indicated that Light voices differed from all other voice types across acoustic and aerodynamic measures. The DFA did not reliably classify or predict group membership based on these metrics. Inter-rater 75% agreement among listeners was low for both voice quality contrasts (Light/Dark = 44%, Front/Back = 36%). Conclusions: The current findings show that performers’ internalized representations of Front, Back, Light, and Dark were not aligned with voice professionals’ ratings of their productions, which may contribute to challenges in therapy or vocal instruction. This misalignment is further reflected in the wide variety of terms used to describe voice qualities in open-ended responses, suggesting a possible need for more standardized terminology.
Barone et al. (Mon,) studied this question.