The achievement of ensemble

This paper discusses the various ways in which groups of musicians synchronise their performance. A player's 'internal clock' controls the timing of his playing actions, but is constantly checked against acoustical and visual cues from others. Acoustical cues occur in two forms, one produced by disagreements between supposedly coincident attacks, the other produced by hearing note-onsets in others parts which precede one's own onsets by known notational durations. Consensus is achieved by balancing conflicting cues, and by a hierarchy of responsibility amongst the players. This hierarchy changes with time as the musical context varies. The detection and correction of errors are subject to a 'time constant' effect. This promotes a stable tempo, but limits responsiveness to true tempo changes. The mechanisms of ensemble playing aggravate problems caused by propagation delay. It is suggested that ensemble information is contained principally in the level vs. time envelope of music signals, and that Modulation Transfer Functions offer a fruitful approach to the study of ensemble. © 1988.