Acoustic correlates of diphthong and hiatus production in L2 Spanish learners

English and Spanish differ in syllable formation. One difference is that certain vocoid sequences in English are produced in hiatus, whereas the same vocoid sequences in Spanish are produced either as a diphthong or as a hiatus, subject to phonological conditioning. This difference may contribute to crosslinguistic interference in first language (L1) English speakers producing vocoid sequences in second language (L2) Spanish. This interference may increase in cognates (e.g., piano). This paper analyses diphthong/hiatus production in L2 Spanish, to explore acoustic contrast of diphthong/hiatus and test whether production is modulated by L2 proficiency and cognate status. L2 learners and L1 speakers read Spanish words containing the sequence /ia/. Duration and formant trajectories were analyzed. L1 Spanish speakers produced the expected diphthong/hiatus contrast, but L2 learners did not. Learners’ production was modulated by proficiency, starting with a diphthong bias, instead of the expected hiatus bias. There were no strong cognate effects.