Acoustic properties for dental and alveolar stop consonants: a cross-language study

Abstract

This study explored whether there exists an invariant acoustic property which can distinguish dental from alveolar stop consonants. Experiment I investigated dental and alveolar stops in Malayalam, a language which uses these sounds contrastively. It was found that a measure of the rms amplitude of the burst normalized to the rms amplitude of the vowel could distinguish the two classes of stop consonants. The rms amplitude of alveolar stops is larger than that of dental stops. Using a difference of approximately 14 dB between the amplitude of the burst and that of the vowel as a cut-off between denter and alveolar stops, 91.8% of the data could be classified correctly. Experiment II explored whether the metric established for Malayalam could correctly characterize dental and alveolar stops in two languages that have either dental or alveolar stops, but that do not contrast these two classes of stop consonants. The burst amplitude for English CV and for Dutch CV(C) syllables was analysed. Results showed that for English only 68.2% of the alveolars, and for Dutch only 63.2% of the dentals, were classified correctly. Implications of these findings for a theory of acoustic invariance are discussed.