Acoustic correlates of stressed vowels in Spanish spoken in Colombia

Abstract The primary objective of this study is to identify the most salient prosodic features at the sentence level in Colombian Spanish. Data were collected from the country’s major cities, and the study examines the intensity, duration, and pitch (F0) of vowels in pre-stressed, stressed, and post-stressed syllables within both statements and questions. Stressed vowels were compared to adjacent unstressed vowels to determine the most significant features for identifying vowel prominence. The results indicate that duration is the most consistent acoustic cue of stress, reliably distinguishing stressed vowels from adjacent unstressed vowels. In contrast, intensity predicts stress only in relation to post-stressed vowels, and F0 plays a limited role, distinguishing stressed from post-stressed vowels in specific contexts. An important contribution of this study is the demonstration that the stressed versus unstressed distinction in Spanish is primarily explained by duration, rather than F0. These findings challenge traditional classifications of Spanish as a syllable-timed language by showing that rhythmic grouping, previously thought to be exclusive to stress-timed languages, is also present in syllable-timed languages.