Variation in formant dynamics of L1 and L2 Spanish vowels

The present study describes the nature of the dynamic spectral changes of Spanish vowels /a e o/ produced by 10 native Spanish (L1) speakers and 13 native English speakers learning Spanish as a second language (L2). The investigation seeks to identify variations in formant change through the application of both two- and three-point measures, evaluating their efficacy in capturing the formant dynamics of Spanish vowels. F1 and F2 formant dynamic variations were assessed in a set of acoustic measures, including Vector Length (VL), Trajectory Length (TL) and Formant Velocity (FV). Results show that L1 Spanish vowels are more dynamic than L2 Spanish vowels produced by native English speakers, challenging the traditional view that Spanish vowels are rather static. Moreover, the findings indicate that two- and three-point measures yield similar results for most vowels regarding the amount of formant change, rendering them ineffective in accurately describing Spanish vowels. The main difference between L1 and L2 Spanish vowels lies not in the magnitude of formant change, but in the direction of such change. Consequently, a measure that incorporates the direction of formant movement, such as FV, emerges as a more suitable acoustic characterization for both L1 and L2 Spanish vowels.