Resonance Tuning in Three Girl Choristers

The phenomenon of resonance tuning, whereby a singer modifies the shape of their vocal tract to increase the acoustic power output, is commonly exploited across large pitch ranges by professional sopranos and has been observed to a lesser degree in nonexpert adult singers. This study considers the employment of two common resonance tuning techniques in experienced child singers; tuning the first vocal tract resonance to the fundamental (R₁: f_o) and tuning the second resonance to the second harmonic (R₂:2 f_o).

Wide-band excitation at the subject's mouth during singing was used to measure the vocal tract resonances of three girl choristers, and vowel formant values in speech were extracted from samples of spoken text. Measured resonance values were cross-referenced with first and second harmonics for sung vowels across the subjects' ranges to identify the resonance tuning techniques employed, and these results were compared with those previously observed by others in professional adult classical singers.

There was clear evidence that the subjects employed resonance tuning techniques comparable with the strategies used by adult singers. The protocol and results presented here pave the way for further studies exploring the development of resonance tuning techniques in young soprano voices, with the potential to impact on approaches to classical singing training in the future.