The four-part chorales of Bach become excellent material for trumpet ensembles in intonation and interaction. Wenger uses alternate dynamics, voice switching, and more to encourage players to listen carefully to each other, and often uses the Chorales as warm-up material. Published in score form, so that each player sees what the others are doing, and to facilitate voice switching in practice, it is recommended that a score is shared by no more than two players. For intermediate to advanced.