/l/ variation in American English: A corpus approach

We investigated the variation of /l/ in a large speech corpus through forced alignment. The results demonstrated that there is a categorical distinction between dark and light /l/ in American English. /l/ in syllable onset is light, and /l/ in syllable coda is dark. Intervocalic /l/ can be either light or dark, depending on the stress of the vowels. There is a correlation between duration (the rime duration and the duration of /l/) and /l/-darkness for dark /l/, but not for light /l/. Intervocalic dark /l/ is less dark than canonical syllable-coda /l/, but it is always dark, even in very short rimes. Intervocalic light /l/ is less light than canonical syllable-onset /l/, but it is always light. We argue that there are two levels of contrast in /l/ variation. The first level is determined by its affiliation to a single position in the syllable structure, and the second level is determined by its phonetic context.