The Influence of Pre- and Postplosive Fundamental Frequency on /t/–/d/ Perception in German

Abstract

This paper is concerned with the dependence of segment perception on microprosodic perturbations of a macroprosodic intonation contour. The test paradigm involves tokens of the German word pair ‘leiten’/’leiden’, where the vowel and closure durations are simultaneously manipulated. A falling versus a flattish fundamental frequency contour during the diphthong is shown to bias phoneme judgements towards lenis. As regards variation of F₀ in the syllabic nasal (falling vs. flattish vs. rising) both falling and rising contours cause an increase in fortis judgements. Furthermore, variations of F₀ in the vowel and in the nasal do not interact. In view of the necessity to use LPC synthetic speech as a tool in F₀ manipulation, the potential artefact of LPC synthesis in these experiments on F₀-conditioned segment perception is also investigated. The use of a synthetic instead of a natural vowel quality shifts the phoneme boundary towards more lenis, though this effect is weak.