Chants across seven traditions share acoustic traits that enhance subjective relaxation

Significance This research presents evidence that chants possess distinct acoustic characteristics compared to speech and other genres of singing. Across different cultures, chants share common characteristics such as predominantly flat and slow-changing intonation, consistent and uninterrupted voicing in a comfortably low pitch range, minimal vibrato-like inflections, and a high proportion of mid-central vowels. Furthermore, this study demonstrates the impact of these acoustic features on subjective well-being, particularly in terms of promoting relaxation, implying that the acoustic form of chants has evolved culturally to optimize listener relaxation.