Perceptive and acoustic analysis in forensic phonetics: research in voice disguise

• Autor(a) principal: Gomes, Maria Lucia de Castro
• Data de Publicação: 2016
• Outros Autores: Carneiro, Denise de Oliveira, Dresch, Andrea Alves Guimarães
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Domínios de Lingu@gem
• Texto Completo: https://seer.ufu.br/index.php/dominiosdelinguagem/article/view/31650
• topic: Análise Perceptiva; Aanálise Acústica; Fonética Forense; Disfarce de Voz; Análise de vogais; Perceptive analysis; Acoustic analysis; Forensic phonetics; Voice disguise; Vowel analysis

The main objective of this research was to introduce a group of undergraduate students in activities of perceptual and acoustic analysis in a forensic context. A 75-word text  was created to simulate a kidnapping situation. Fifty participants, in groups of ten according to gender and age, were recorded reading the text in a normal voice and then disguising their voice. For the perceptive analysis, we used the VPAS protocol (LAVER 1980; CAMARGO AND MADUREIRA, 2008), and six researchers (judges) analyzed the voices. For the acoustic analysis, we used PRAAT for measuring duration, F0, F1 and F2. Male and female voices were compared and some results confirm some universal trends: vowel intrinsic duration, in which the lower vowels are longer than the higher vowels; female informants have ​​F0, F1 and F2 higher frequency values than males; women have larger vowel spaces than men. The most common settings for voice disguise were: open jaw and lip protrusion, as supra-laryngeal settings, falsetto and harsh voice, as phonation settings.