The contribution of vowel coarticulation and prosodic weakening in initial and final fricatives to sound change

This paper is concerned with the influence of vocalic context (/ɪ, ʊ/) and prosodic weakening on the production of the German fricatives /s, ʃ/ in two syllable positions and its relation to the frequent sound change from alveolar to post-alveolar fricatives. Previous studies reported coarticulatory influences of vowel context on fricatives and more coarticulation in prosodically weak positions. However, the influence of syllable position is unclear, even though sound change affects more often segments in coda than in onset position. In order to test these factors, acoustic and articulatory data from six German speakers were analysed. They produced lexical words with fricatives in onsets and codas of stressed syllables in accented and deaccented words. The results show a small influence of syllable position on the analysed acoustic and articulatory measurements, with higher spectral centers of gravity and more retracted mean tongue trajectories in coda position.