As part of the global Many Voices 2 project, I contribute to cross-cultural research on how music and language influence social connection. The study involves over 1,700 participants across 57 research sites on six continents, examining how activities like synchronized singing, turn-taking in song, synchronized speech, and natural conversation affect social bonding. Grounded in the social bonding hypothesis which suggests that singing may foster stronger connections than speech, the project investigates the role of vocal coordination in human interaction. My contribution focuses on experimental coordination and data collection at the London site. Preliminary results support the idea that musical synchrony strengthens social bonding more than the speaking condition.