They Instruct the Group as well when/how to do something.

1. 1. a person who directs the performance of an orchestra or choir."he was appointed principal conductor of the Berlin Philharmonic Orchestra"
2. 2. NORTH AMERICANa person in charge of a train, streetcar, or other public conveyance, who collects fares and sells tickets.

Conducting is the art of directing a musical performance by way of visible gestures. The primary duties of the conductor are to unify performers, set the tempo, execute clear preparations and beats, and to listen critically and shape the sound of the ensemble.^[1]

Conductors act as guides to the orchestras and/or choirs they conduct. They choose the works to be performed and study their scores to which they may make certain adjustments, work out their interpretation, and relay their ideas to the performers. They may also attend to organizational matters, such as scheduling rehearsals.^[2] Orchestras, choirs, concert bands and other sizable musical ensembles are usually led by conductors.

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