Chef d'orchestre

Conducting is the art of directing a musical performance, such as an orchestral or choral concert. It has been defined as "the art of directing the simultaneous performance of several players or singers by the use of gesture." The primary duties of the conductor are to interpret the score created by a composer in a manner which is reflective of the specific indications within that score, set the tempo, ensure correct entries by various members of the ensemble, and to "shape" the phrasing where appropriate. To convey their ideas and interpretation, conductors communicate with their musicians primarily through hand gestures, typically though not invariably with the aid of a baton, and may use other gestures or signals, such as eye contact with relevant performers. A conductor's directions will almost invariably be supplemented or reinforced by verbal instructions or suggestions to their musicians in rehearsal prior to a performance.

The conductor typically stands on a raised podium with a large music stand for the full score, which contains the musical notation for all the instruments or voices. Since the mid-19th century, most conductors have not played an instrument when conducting, although in earlier periods of classical music history, leading an ensemble while playing an instrument was common. In Baroque music from the 1600s to the 1750s, the group would typically be led by the harpsichordist or first violinist (see concertmaster), an approach that in modern times has been revived by several music directors for music from this period. Conducting while playing a piano or synthesizer may also be done with musical theatre pit orchestras. Communication is typically non-verbal during a performance (this is strictly the case in art music, but in jazz big bands or large pop ensembles, there may be occasional spoken instructions, such as a "count in"). However, in rehearsals, frequent interruptions allow the conductor to give verbal directions as to how the music should be played or sung.

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