Acoustic correlates of primary and secondary stress in North American English

This study investigates the acoustic correlates of the distinction between primary and secondary stress in English in accented and unaccented morphologically complex words that are either left-prominent or right-prominent (e.g. "violate vs. vio"lation). In both accented and unaccented words, the position of primary and secondary stress significantly influences F0, intensity, and spectral balance. The effects are, however, much weaker for unaccented words. A model is presented which can, for accented words, very successfully distinguish the two stress patterns on the basis of pitch, intensity, duration, spectral balance in the two stressed syllables and the pitch slope in the left position. In contrast, the stress patterns of unaccented words cannot be successfully detected on the basis of the acoustic parameters. The findings strongly support an accent-based phonological account of the primary-secondary stress distinction. Primary and secondary stress syllables are not different from each other, unless the word is pitch-accented. In this case what is usually labeled the primary stress syllable becomes the target of a nuclear accent. Left-prominent accented words receive one accent, right-prominent accented words two accents.1