Acoustic characterization of the Costa Rican Non-Standard Trills

Abstract

This study characterizes the Costa Rican Spanish trill realizations acoustically, identifies the number of variants, and determines if they are acoustically distinguishable. Costa Rican trills typically lack vibration of the tongue tip and are thus categorized as ‘non-canonical’ compared to the normative rolled trill. Only impressionistic descriptions have been provided, posing challenges to comparisons across studies and dialects. Using Audacity, 18 speakers (9 female, M = 37.4) recorded their productions of 72 tokens containing the trill in word-initial/medial position and in stressed/unstressed syllables. The study was conducted remotely through Gorilla Experiment Builder. Duration, percentage of voicing and center of gravity were measured in PRAAT. Classification was based on visual inspection of the spectrograms and waveform, with the audio as a guide. ANOVAs were used to examine the distribution of the variants and their acoustic differences. Ten categories are characterized acoustically, the fricative being the most common variant. Stress made realizations longer but did not reach significance. Word-initially, fricatives and trills had a significantly higher percentage of devoicing, and while approximants and trills tended to be shorter in this position, fricatives had the opposite direction of effect. Fricatives also showed considerable variation in center of gravity (M = 2159.2 Hz, Range = 5622.3 Hz). This acoustic description of the non-standard variants serves as a parameter for future comparisons with other dialects.