Modeling consonant-context effects in a large database of spontaneous speech recordings

Abstract

Given recent interest in the analysis of naturally produced spontaneous speech, a large database of speech samples from the Canadian Maritimes was collected, processed, and analyzed with the primary aim of examining vowel-inherent spectral change in formant trajectories. Although it takes few resources to collect a large sample of audio recordings, the analysis of spontaneous speech introduces a number of difficulties compared to that of laboratory citation speech: Surrounding consonants may have a large influence on vowel formant frequencies and the distribution of consonant contexts is highly unbalanced. To overcome these problems, a statistical procedure inspired by that of Broad and Clermont [(2014). J. Phon. 47, 47-80] was developed to estimate the magnitude of both onset and coda effects on vowel formant frequencies. Estimates of vowel target formant frequencies and the parameters associated with consonant-context effects were allowed to vary freely across the duration of the vocalic portion of a syllable which facilitated the examination of vowel-inherent spectral change. Thirty-five hours of recorded speech samples from 223 speakers were automatically segmented and formant-frequency values were measured for all stressed vowels in the database. Consonant effects were accounted for to produce context-normalized vowel formant frequencies that varied across time.

Designing Virtual, Moderated Studies of Early Childhood Development

“…Such misperception was not present in our in-person pilot work, and we suspect this to be caused by variability among audio devices and sound settings across participants. We note that the rare instances of misperception occurred only in trials containing the stimulus /i/, and vowel productions in a /h/−onset context have been shown to be virtually identical to those observed in isolation ( Kiefte and Nearey, 2017). As a future step, we will explore the option of using experiment builders (as in the AV study) to deliver the stimuli for better control over the variability in audio signal transmissions.…”