An Old Myth: Prediction of the Correct Singing Voice Classification. True or not?

Abstract

Objective: Predicting the correct singing voice classification based on laryngoscopy is an old myth. The aim of this study was to evaluate if a professional phoniatrician/laryngologist can predict the correct singing voice classification only from laryngoscopy and to analyze different anatomical parameters between professional sopranos and altos to determine whether a multivariate analysis of anatomical parameters can predict the singing register.

Study design: Prospective study METHODS: We included 49 professional female singers (25 sopranos, 24 altos). Laryngoscopic images were shown to professional phoniatricians/laryngologists to rate whether it they show a soprano or an alto. In addition, a high-resolution computer tomography (HRCT) scan was performed during singing of ƒ0 by each singer. DICOM scan data were rendered and 3D-visualized using the software MIMICS. In all singers, we measured the length of the vocal folds of the glottis, the distance from the anterior commissure orthogonally to the vertebral spine, and the antero-posterior distance of the subglottis/trachea 1 cm and 2 cm below the glottis. We also measured the length and volume of the resonance space.

Results: It was not possible to predict the singing voice classification only from laryngoscopy. In the HRCT images, sopranos had significantly shorter vocal folds, a shorter glottal length, a shorter distance from the anterior commissure to the spine, and a shorter resonance space. When combining all parameters, the chance of correctly predicting a soprano was 74.1% and an alto 68.2%.

Conclusion: Although there are anatomical differences between sopranos and altos, prediction of the singing voice classification from laryngoscopy or HRCT is not reliable enough for clinical use.

Keywords: 3D; Laryngoscopy; Professional singer; Resonance space; Singing voice classification; Vocal fold length.