Global Acoustic Parameters Dataset: Forensic Speaker Comparison under Voice Disguise Conditions (Brazilian Portuguese)

This dataset contains a comma-separated values (CSV) file with global acoustic parameters extracted for a study on voice disguise and the robustness of acoustic descriptors in forensic speaker comparison. The data were collected as part of a Master’s thesis conducted at the Institute of Language Studies, State University of Campinas (UNICAMP), focusing on Brazilian Portuguese.The dataset comprises measurements from ten native speakers of Brazilian Portuguese (five male and five female, mean age ≈ 25 years). Participants read a standardized narrative text—an adapted excerpt from <i>A Menina do Narizinho Arrebitado</i> by Monteiro Lobato (public domain, approximately 1,049 words)—designed to elicit naturalistic speech while maintaining experimental control.Recordings were carried out in a sound-treated environment using a Zoom H4N PRO digital recorder at a sampling rate of 44.1 kHz and 32-bit resolution. Each speaker was recorded under seven speaking conditions: (i) natural voice (control), (ii) lowered fundamental frequency (F0), (iii) raised F0, (iv) hoarse voice, (v) nasal obstruction (holding the nose), (vi) mechanical obstruction (pencil held between the teeth), and (vii) use of an N95 mask.Global acoustic parameters were extracted using Praat software by combining outputs from two specialized scripts: the <i>Prosody Descriptor Extractor</i> (Barbosa, 2021), used to obtain fundamental frequency statistics, intensity, and spectral balance measures; and the <i>Acoustic Parameters Descriptor for Forensics (APD)</i> (Barbosa, 2018), used to extract global formant-related measures. The dataset includes F0 statistics (e.g., mean, median, standard deviation, range, quartiles, skewness, and peak measures), first-derivative F0 metrics, mean and median values for formant frequencies (F1–F4), and voice quality and intensity measures such as jitter, shimmer, harmonics-to-noise ratio (HNR), and spectral emphasis.Prior to analysis, the data were preprocessed to remove outliers using the interquartile range (IQR) method (threshold = 1.5), following the procedures described in the associated thesis.The research was funded by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), process no. 88887.807823/2023-00. Data collection followed ethical standards for research involving human participants.