Contributions of acoustic measures to the classification of laryngeal voice quality in continuous English speech

Laryngeal voice qualities (e.g. breathy and creaky voice), variable within and across speakers, often pose a challenge in data collection. Their acoustic correlates are still inadequately understood. This study revisits the acoustics of laryngeal voice qualities in high-quality recordings of continuous British English speech produced by experienced phoneticians. Through principal component analysis and multinomial logistic regression with l1 regularisation, this study identifies contributions of a variety of acoustic measures to the classification of laryngeal voice qualities and provides a multidimensional acoustic profile for breathy, creaky, and modal voice. Classification rates as high as 90% were achieved using the first 5 principal components. The most salient acoustic correlates for creaky voice are, compared to other categories, higher mean H2*, lower mean f0 and HNR below 500 Hz, and for breathy voice, higher mean H1* and spectral tilt measures such as H1*–A1* and H1*–H2*.