Patterns of voicing-conditioned vowel duration in French and English

Because the variation in vowel duration conditioned by following obstruent voicing has been found to be much greater in English than in other languages, a phonological rule of vowel-lengthening has been proposed for English. This conclusion, however, has been based on studies that do not take into account a number of other factors which influence vowel duration. A comparison of vowel duration in English and French monosyllables shows that, particularly sentence-finally and medially under focus, when inter-language differences in final obstruent realization are taken into account, obstruent voicing has a substantial influence on vowel duration in both languages. In words occurring in unstressed medial position, the variation in vowel duration is much smaller, but equally so in both languages, once inter-language differences in prosodic structure and syllable structure are taken into account. These results suggest that languages universally exhibit fairly similar, physiologically conditioned, voicing-dependent variation in vowel durations. Under certain conditions of word length, syllabic structure, stress, position in word and utterance, and speaking tempo, voicing-induced differences are enhanced, while under others they are obscured. A general phonetic account in terms of timing control thus seems more appropriate than a language-specific phonological rule, even for a language like English.