The distribution of speaker information in Dutch fricatives /s/ and /x/ from telephone dialogues

Although previous work has shown that some speech sounds are more speaker-specific than others, not much is known about the speaker information of the same segment in different linguistic contexts. The present study, therefore, investigated whether Dutch fricatives /s/ and /x/ from telephone dialogues contain differential speaker information as a function of syllabic position and labial co-articulation. These linguistic effects, established in earlier work on read broadband speech, were first investigated. Using a corpus of Dutch telephone speech, results showed that the telephone bandwidth captures the expected effects of perseverative and anticipatory labialization for dorsal fricative /x/, for which spectral peaks fall within the telephone band, but not for coronal fricative /s/, for which the spectral peak falls outside the telephone band. Multinomial logistic regression shows that /s/ contains slightly more speaker information than /x/ in telephone speech and that speaker information is distributed across the speech signal in a systematic way; even though differences in classification accuracy were small, codas and tokens with labial neighbors yielded higher scores than onsets and tokens with non-labial neighbors for both /s/ and /x/. These findings indicate that speaker information in the same speech sound is not the same across linguistic contexts.