Variability in Acoustic, Physiological, and Perceptual Features of Belting Among Adult Singers: A Scoping Review

Belting is a vocal quality commonly used across contemporary singing genres. Despite its ubiquity, belting production and perception are highly debated. Variable methodologies and terminology used to discuss, teach, and study belting limit our understanding of underlying mechanisms and restrict the development of science-informed voice pedagogy. We systematically examined the published literature on belting to identify commonalities, disagreements, and directions for future research.

We conducted a scoping review surveying English-language peer-reviewed scientific studies and pedagogical publications on belting in adult singers that were published between January 1978 and November 2025. Data were extracted and grouped into the following categories: perception, acoustics, physiology, and pedagogy.

In total, 2018 publications were reviewed. 472 underwent full-text review, and 112 met inclusion criteria, comprising 58 scientific studies and 54 pedagogical publications. Most scientific studies were cross-sectional comparing the same group or population across variable tasks (n = 25), and pedagogical publications were largely expert commentary (n = 32). Perceptually, belting was characterized as having "bright" or "forward" resonance and increased loudness. Acoustic findings included higher first and second formant frequencies, with the first formant tuned to the second harmonic. Physiologically, belting was associated with an elevated laryngeal position, pharyngeal narrowing, closed quotient >50%, high subglottal pressure, and "megaphone" mouth shape. High individual variability was a hallmark of all findings. Terminology was highly variable, with over 100 words and phrases used to describe belting.

High variability of findings suggests that belting is better understood as a family of related vocal behaviors than as a single, homogeneous phenomenon. We propose three tenets for future work: (1) use of objective acoustic and physiological terminology to define belting, (2) inclusion of multiple terminologies where appropriate to reflect the diversity of learning styles and individual physicality, and (3) use of auditory anchors to supplement written definitions and reduce perceptual ambiguity.