Of the musical kind. In case you wondered whether the orchestra conductors just waved in the randomly or not, the techniques section should help clarify any doubts:
“Conducting is a means of communicating artistic directions to performers during a performance. Although there are many formal rules on how to conduct correctly, others are subjective, and a wide variety of different conducting styles exist depending upon the training and sophistication of the conductor. The primary responsibilities 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. Communication is non-verbal during a performance, however in rehearsal frequent interruptions allow directions as to how the music should be played.”
Tags: wikipedia, music, technique
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