Journal of Phonetics (1996) 24, 351 – 365 Early bilingual acquisition of the voicing contrast in English and Spanish Margaret Deuchar* Uni ersity of Wales , Bangor , U.K. Angeles Clark Uni ersity of Sussex , U.K. Recei ed 29th December 1993 , and in re ised form 31st January 1996 A case study of a child acquiring English and Spanish in England between the ages of 1;7 and 2;3 is presented. VOT measurements of utterance-initial stops in English and Spanish were made of productions at ages 1;7, 1;11, and 2;3. Similar measurements of the parents’ Spanish speech were made. While the child had developed an adult-like voicing contrast in English by age 2;3, she had not done so in Spanish. However, there were signs of a contrast developing in Spanish, based on small lag dif ferences. Similar lag dif ferences were found in the input. The results are accounted for in terms of the relatively greater acoustic salience of the lag dif ferences in English compared with those in Spanish. ÷ 1996 Academic Press Limited 1. Introduction This paper reports on the results from a case study of a child acquiring English and Spanish from birth. The focus is on the acquisition of voicing in utterance-initial stops, and the aim is to throw new light on the process whereby the child acquires a contrast which has dif ferent phonetic realizations in the two languages. English and Spanish are similar in that the presence or absence of voicing represents a binary contrast between stops, which may be classified phonemically in both languages as either voiced or voiceless. However, the phonetic basis for the distinction between voiced and voiceless stops is not the same in the two languages. Whereas voiced stops in utterance-initial position in Spanish are characterized by the vibration of the vocal cords beginning before the release of the closure, utterance-initial voiced stops in English may have this characteristic, but more frequently are characterized by the onset of voicing occurring shortly after the release of the closure. Utterance-initial voiceless stops in the two languages also dif fer in terms of the timing of the beginning of vocal cord vibration. Whereas in Spanish voiceless stops, vocal cord vibration begins shortly after the release of the closure (as it does in many English ‘‘voiced’’ stops), in English voiceless stops it begins after a time interval of roughly 60 – 80 milliseconds on average. These * Please address all correspondence to: M. Deuchar, Department of Linguistics, School of English and Linguistics, University of Wales, Bangor, Gwynedd LL57 2DG, U.K. 0095-4470 / 96 / 030351 + 15 $18.00 / 0 ÷ 1996 Academic Press Limited