ACOUSTIC DISPERSION SCALES FOR STRESSED DIPHTHONGS IN TWO VARIETIES OF PORTUGUESE

São Tomé and Príncipe Portuguese and Brazilian Portuguese

Abstract

The aim of this paper is to analyze the oral falling diphthongs in two varieties of Portuguese: São Tomé and Príncipe Portuguese (PSTP) and Brazilian Portuguese (PB). To do so, based on a corpus formed from lexical items elicited through carrier sentences, collected in the field on the islands of São Tomé and Príncipe, West Africa, we extracted the first and second formant (F1 and F2) values of stressed oral vowels using PRAAT. This methodological procedure was carried out in order to establish the acoustic dispersion between the vowel (V) and the glide (G) that form the falling diphthongs in PSTP. Once the acoustic dispersion between VG was calculated, we established a dispersion scale comprising four points: high dispersion, medium dispersion, low dispersion, and very low dispersion. This scale was then compared to the scale proposed by Eberle (2022) for PB. Finally, by contrasting both scales, some differences were observed in terms of the acoustic contrast between V and G of the oral diphthongs in PSTP and PB. These differences seem to stem primarily from the insertion of [ə] in the stressed oral vowel system of PSTP