Physiological and acoustic characteristics of the female Music Theater voice.

Three Music Theater vocal qualities ("chesty belt," "twangy belt," and "legit") were investigated in female singers at their overlap range, between F#4-D5 (~370-600 Hz). Six experienced Music Theater singers performed each quality on two different vowels ([e], [ɔ]). Audio and electroglottographic (EGG) signals were recorded as well as the vocal tract impedance. In chesty belt and twangy belt, singers systematically tuned the frequency of their first vocal tract resonance (R1) to the second harmonic (2f(0)) up to C5. R1 remained lower in frequency for the legit quality. No tuning of the second vocal tract resonance (R2) was observed in any of these qualities although R2 frequency was significantly higher in both belt qualities than in legit. Closed quotient, degree of symmetry of the EGG waveform, sound pressure level (SPL) and the energy of the spectrum above 1 kHz were significantly greater in chesty belt than in legit but not significantly different between chesty belt and twangy belt qualities. A fourth quality ("mix") was explored in three singers. Different production strategies were observed for each singer, with values of spectral, glottal and vocal tract descriptors found in between those measured for legit and chesty belt qualities.