Language as systematic code is contrasted with languaging, a broader term to include many different kinds of social and affiliative forms of coordination involving voice. The study of language is important to understand contemporary entities like French or Yoruba. However only languaging can inform us about the radical diachronic change that so altered our species. I will introduce joint speech, a term to cover all occasions where multiple people utter the same vocal sounds in unison. This includes practices of chant as found in ritual and prayer, but also in protest and among sports fans. It is a reliable part of the education of young children, and the recurrent forms of chant may exhibit stability over centuries or millennia. Joint speech has many recognisable structural properties that transcend these several domains, and that have not yet been studied. Attention to joint speech reveals continuities with music/musicing that a code-based construal of language obscures. Those widespread activities in which joint speech is found are foundational for the social order in all societies. Recognising joint speech as a distinguished and important form of languaging gives us a new way to consider vocally mediated communication and suggests that communication is only possible among those who share sufficient common ground, or communion. This provides a new and rich frame within which to consider the changes that gave rise to the human social world.