Speaking-rate-induced variability in F2 trajectories

Area of Science:

• Phonetics
• Speech Acoustics
• Linguistics

Background:

• Speaking rate influences speech sound production.
• Understanding acoustic variability is crucial for speech processing models.

Purpose of the Study:

• To investigate how speaking rate affects spectral and temporal variability of F2 formant trajectories.
• To quantify gestural overlap using F2 onset and target frequencies.

Main Methods:

• Analysis of F2 formant trajectories for target words in a carrier phrase.
• Measurement of F2 onset and target frequencies at varying speaking rates (fast to slow).
• Regression and partial correlation analyses to examine relationships between acoustic measures and vowel duration.

Main Results:

• 70% of regression functions relating F2 onset and vowel duration were significant.
• The strength and direction of these effects varied, deviating from simple sliding gesture models.
• Vowel duration covariation with F2 target frequency can obscure F2 onset-vowel duration relationships.

Conclusions:

• A sliding gestures model only partially explains acoustic variability due to speaking rate.
• Individual speaker data show differential adherence to the sliding gestures model.
• Complex interactions between gestural overlap, vowel duration, and speaking rate influence speech acoustics.