Yoruba bata drumming, carried into Cuba and Brazil through the transatlantic slave trade and preserved there within Santeria and Candomble alongside its continuation in Nigeria, is the clearest case of ritual drumming functioning as an actual language rather than a generalised technique for producing a state. The bata is a set of three double-headed, hourglass-shaped drums of graduated size, and skilled players use the two heads of each drum, along with the interaction between the three instruments, to reproduce the tonal patterns of spoken Yoruba, since Yoruba is itself a tonal language in which pitch changes meaning, so that a trained listener can follow proverbs, praise names and specific messages encoded in the drumming rather than experiencing it only as rhythm. Each orisha, the deities of the tradition, has particular rhythms associated with them, and a batalero, a trained bata drummer, must learn an extensive repertoire tied to specific deities and specific points in a ceremony, since playing the wrong rhythm at the wrong moment is considered a real error rather than a stylistic variation, and the drummers themselves undergo initiation and years of apprenticeship before being trusted to play in ceremonial context at all.
The arrival of a possessing orisha during a ceremony is understood by practitioners as bound up with the correct rhythm being played and recognised, which is the opposite of the generic modern account of drumming as a universal trance technique: here the content of what is played, not merely the act of drumming, is what the tradition holds actually matters.