The acoustic and perceptual bases of diachronic /u:/‐fronting in Standard Southern British

Abstract

In a recent experiment concerned with diachronic /u:/‐fronting in Standard Southern British, it was shown both that the /u:/ category boundary was perceptually retracted for older compared with younger listeners of this variety, and that they compensated perceptually to a greater extent for the coarticulatory fronting effects of the preceding consonant on /u:/ in words like used. In the present study, these perceptual differences were related to the same speakers' productions of words containing a /u:/ nucleus in a fronting (e.g., 'used') and non‐fronting (e.g., 'swoop') contexts. The relative acoustic distance of /u:/ between front and back vowels was measured in a three‐dimensional space formed by applying the discrete‐cosine‐transformation to the entire F2‐trajectory shape separately for each speaker. Compatibly with their perceptual responses, older listeners had a more retracted /u:/ on this measure and exhibited a greater coarticulatory influence of the preceding consonant. The mechanism of this sound change is considered both from the point of view of a shift in the perceptual compensation for coarticulation and recent developments in episodic models of speech perception