Predicting and classifying Italian singleton and geminate consonants at various speaking rates using logarithmic duration

Amanoet al. [2021, JASA, 150(3), 1830–1843] showed that a linear function using logarithmic durations can predict and classify Japanese singleton and geminate consonants across various speaking rates. However, it remains unclear whether this function can also be applied to other languages. To address this issue, Italian singleton and geminate consonants were analyzed using four minimal-pair words and four minimal-pair nonwords, each spoken by 15 native Italian speakers in carrier sentences at various speaking rates. Regression and discriminant analyses revealed that a linear function with two variables, the logarithmic duration of the consonant closure and the logarithmic average syllable duration of the carrier sentence, can predict the distributions of singleton (R² = 0.70) and geminate (R² = 0.54) consonants and classify them with a low error rate (4.0%). These findings suggest that the combination of logarithmic durations constitutes an invariant acoustic feature with respect to speaking rate variation, and that this combination is a universal acoustic cue of singleton and geminate consonants across languages.