Stress has notorious and debilitating effects on individuals and entire industries alike, with instances of stress continuing to rise post-pandemic. We investigate here (1) if the new technology of Vibroacoustic Sound Massage (VSM) has beneficial effects on user wellbeing and (2) if we can measure these effects based on the biosignal of speech prosody. Forty participants read a text before and after VSM treatment (45 min). The 80 readings were subjected to a multi-parameteric acoustic-prosodic analysis. Results provided positive answers to (1) and (2), showing that timbre and pitch features were most sensitive to VSM treatment, followed by loudness and pausing. Overall, participants spoke more deeply, softly, and slowly after VSM, suggesting that they were in a more relaxed state. Practical implications and future research perspectives are discussed.

Index Terms— prosody, VSM, biosignals, wellbeing.