Acoustic characteristics of English/n, l, t, k/ produced by native speakers of American English and Japanese at and near the word boundary

Abstract

The acoustic characteristics of English /n, l, t, k/ produced by native speakers of American English and Japanese at and near the word boundary are compared. The phonemes are produced in two-word sequences in sentence contexts, /n/ or /l/ appears at the end of the first word (e.g., an earth, you'll earn) or at the beginning of the second word (e.g., a nurse, you learn), while /t/ or /k/ appears at the beginning of the second word (e.g., stops talking, ice cream) or as the second segment of the initial cluster /sk/ of the second word (e.g., stop stalking, I screamed). Acoustic analysis revealed that English speakers' /n/ in coda position is shorter and creakier, while Japanese speakers' /n/ is as long as in onset. In addition, English speakers' vowels in /Vl#/ context are more velarized than vowels in /V#l/ context, whereas Japanese speakers' vowels in /Vl#/ context are less /l/-colored. English speakers produced initial /t/ and /k/ with much longer VOT than in /st/, /sk/ conditions, but because Japanese voiceless stops are weakly aspirated, Japanese speakers /t/ and /k/ not significantly different in VOT between the two contexts, leading potentially to syllable misparsing by English listeners