Effects of prosodic factors on spectral dynamics. I. Analysis

Abstract

The effects of prosodic factors on the spectral rate of change of vowel transitions are investigated. Thirty two-syllable English words are placed in carrier phrases and read by a single speaker. Liquid-vowel, diphthong, and vowel-liquid transitions are extracted from different prosodic contexts, corresponding to different levels of stress, pitch accent, word position, and speaking style, following a balanced experimental design. The spectral rate of change in these transitions is measured by fitting linear regression lines to the first three formants and computing the root-mean-square of the slopes. Analysis shows that the spectral rate of change increases with linguistic prominence, i.e., in stressed syllables, in accented words, in sentence-medial words, and in hyperarticulated speech. The results are consistent with a contextual view of vowel reduction, where the extent of reduction depends both on the spectral rate of change and on vowel duration. A numerical model of spectral rate of change is proposed, which can be integrated in a system for concatenative speech synthesis, as discussed in Paper II [J. Wouters and M. Macon, J. Acoust. Soc. Am. 111, 428-438 (2002)].

Clear Speech Variants: An Acoustic Study in Parkinson's Disease

“…Contrary to previous clear speech studies (Ferguson & Kewley-Port, 2007;Ferguson & Quené, 2014;Lam et al, 2012;Moon & Lindblom, 1994;Wouters & Macon, 2002; but see Tasko & Grelick, 2010), F2 slope was not affected by any of the nonhabitual conditions. Methodological factors may explain why findings from the current study are different from those reported in previous clear speech studies.…”

“…For example, clear speech studies have reported increased VSAs (Bradlow, Kraus, & Hayes, 2003;Ferguson & Kewley-Port, 2002Johnson, Flemming, & Wright, 1993;Lam et al, 2012;Moon & Lindblom, 1994;Picheny, Durlach, & Braida, 1986; but see Krause & Braida, 2004) and increased rates of spectral change in clearly produced monophthongs, diphthongs, and liquid transitions relative to conversational speech (Ferguson & Kewley-Port, 2007;Ferguson & Quené, 2014;Lam et al, 2012;Moon & Lindblom, 1994;Wouters & Macon, 2002; but see Tasko & Greilick, 2010). Clear speech effects have also been studied in consonants produced by healthy speakers, wherein clearly produced fricatives tend to be longer in duration (Maniwa, Jongman, & Wade, 2009).…”

“…In previous clear speech studies, a variety of measures and vowel segments (monophthongs or diphthongs) were used to capture dynamic characteristics of vowels. For example, some studies used a composite measure of F1 and F2 to describe dynamic spectral characteristics in monophthongs (Ferguson & KewleyPort, 2007;Ferguson & Quené, 2014;Lam et al, 2012) and diphthongs (Tasko & Grelick, 2010), whereas Wouters and Macon (2002) fit linear regression lines to formant trajectories for the first three formants of monophthongs and diphthongs. This variation in measure and segment type makes it difficult to compare results across clear speech studies.…”

Effects of the Rate of Formant-Frequency Variation on the Grouping of Formants in Speech Perception

“…In particular, it should be noted that changes in the rate of formantfrequency change are common concomitants of changes in speech rate (e.g., Pitermann 2000; Wouters and Macon 2002;Weismer and Berry 2003). For example, the data reported by Weismer and Berry (2003) show that, for each of their six talkers, increases in speech rate of CVC syllables resulted in increases in the rate of second formant transitionsmean F2 rate of change (estimated from their Figure 5) increased from 4.9 Hz/ms for the slowest speech rate to 12.4 Hz/ms for the fastest, a fast/slow ratio of 2.5.…”

Linguistic variation, identity construction and cognition

“…Vowel duration (Edwards, Beckman & Fletcher 1992), formant transitions in diphthongs (Wouters & Macon 2002), glottalistion (Dilley, Shattuck-Hufnagel & Ostendorf 1996), and consonant realisation (Fougeron & Keating 1997) all appear to be linked to prosodic position; greater articulatory effort tends to be observed at the edges of prosodic domains (Fougeron & Keating 1997). While only one of the analysed tokens in the current study occurred at a sentence boundary, this does not ensure that the observed phonetic differences between the different functions of like were not in fact due to the token's prosodic position in the sentence.…”