Respiratory and Acoustical Differences Between Belt and Neutral Style of Singing

Objectives: Belt is a style of singing commonly used in nonclassical genres. Its respiratory, phonatory, and resonatory characteristics are unclear.

Design: Basic research.

Methods: Six female singers, professionally performing in the belt styles since many years, sang an excerpt of a song in belt and nonbelt/neutral style, two times with the lyrics and two times replacing the lyrics with /pae/ syllables. On separate channels, recordings were made of audio, oral pressure, and rib cage and abdominal wall movements, as picked up by respiratory inductive plethysmography. Lung volume and breathing patterns during inhalation and phonation were normalized with respect to duration and averaged. Voice source was analyzed in terms of flow glottograms derived from the audio signal by inverse filtering.

Results: Belt was produced with higher pressures and yielded higher sound levels, but no consistent breathing pattern was observed, neither for the belt, nor for the neutral style. Voice source differences suggested that belt was produced with firmer glottal adduction than neutral. Also, in four of the singers, the first formant was closer to a spectrum harmonic in belt than in neutral.

Conclusions: Belt style of singing is not associated with a characteristic breathing behavior but is produced with higher subglottal pressures, higher sound levels, and firmer glottal adduction than a neutral style of singing.