Effects of age and experience on the production of English word-final stops by Korean speakers

This study examined the effect of second language (L2) age of acquisition and amount of experience on the production of word-final stop consonant voicing by adult native Korean learners of English. Thirty learners, who differed in amount of L2 experience and age of L2 exposure, and 10 native English speakers produced 8 English monosyllabic words ending in voiced and voiceless stops. These productions were presented to 10 English listeners for perceptual judgment and subjected to acoustic analyses to determine how well learners produced vowel duration and closure (stop gap) duration, two cues to stop consonant voicing. Results revealed that even learners with 10 years of L2 experience did not always produce stop consonant voicing accurately, that learners’ age of acquisition influenced their production of both cues, that vowel duration was easier to learn than closure duration, and that English listeners used both these cues in their judgments of production accuracy.