/u/-fronting in English speakers' L1 but not in their L2

This paper presents an acoustic analysis of the three corner vowels in the Diapix Foreign Language corpus (DIAPIX-FL) which contains material from English and Spanish native speakers from both their L1 and L2. We investigated how L1 vowel characteristics influence the production of L2 vowels, and to what extent a current sound change in one of the languages is reflected in the other. We find that /u/-fronting in English occurs for both native and non-native speakers, although the degree of /u/-fronting is much larger for the English group. English speakers appear to create a separate category for the L2 /u/ rather than use their L1 sound. Spanish speakers show some adjustment to their English /u/ and /a/ realisations. These findings suggest that despite limited exposure to the L2 sounds, learners are aware of realisational differences between the languages and implement them to different degrees even for non-standard variants.