The Effect of Vocal Effort on Voice Quality in Occupations with High Vocal Load

Phonation type identification and voice quality analysis are often performed using invasive methods such as laryngoscopy or fiberoscopy. This work aims to determine whether comparable results can be reproduced using acoustic analysis, a noninvasive method. The research consists of two series of experiments conducted on two separate groups of professional voice users to calculate the values of voice quality parameters (i.e., peak slope, normalized amplitude quotient, cepstral peak prominence, harmonics-to-noise ratio). The first experiment focused on recording voice in the sound studio (22 participants), while the second focused on collecting data using a dedicated mobile app outside the sound studio (20 participants). The collected samples were then analyzed to examine the effects of vocal load on voice quality and to determine variations between different groups of test participants. According to the results of the experiments, vocal load and working professionally with voice change the value of normalized amplitude quotient (NAQ). Furthermore, it has been shown that harmonics-to-noise ratio (HNR) and cepstral peak performance (CPP) vary with regular hydration status. Keywords: voice quality, acoustic analysis, vocal load, vocal exhaustion, phonation type, hydration