Large-scale acoustic characterization of mid-low vowels across American, British, and Singaporean children

Abstract

This study compares how American, British and Singaporean children differ in their production of mid-low vowels. Read speech was collected from 6–13 years old American children (140 speakers, 43 406 utterances), British children (82 speakers, 32 542 utterances) and Singaporean children (192 speakers, 34 457 utterances), with a balanced gender ratio. All three corpora were designed to be phonetically balanced and formant estimates were extracted from the vowel tokens using the Praat software. Our large-scale acoustic analyses show that for TRAP-BATH split vowels, (1) British and Singaporean children both produce these vowels with higher F1, suggesting a relatively lowered tongue height; (2) These vowels have higher F2 (suggesting a more fronted tongue position) for both American and Singaporean children. One-way ANOVA tests reached statistical significance for all these differences; F(2,411) = 34.59, p < 0.001 for F1; F(2,411) = 544.13, p < 0.001 for F2. When comparing /æ/ and /ɛ/ productions, British speakers demonstrate the clearest distinction between the two vowels; Singaporean and American speakers both exhibit a higher and more fronted tongue position for /æ/, causing /æ/ to be more acoustically similar to /ɛ/. One-way ANOVA tests and post hoc Tukey’s test demonstrated that these differences are all statistically significant too (p < 0.001).