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Conductorless orchestras

In the Baroque music era (1600–1750), most orchestras were led by one of the musicians, typically the principal first violin, called the concertmaster. The concertmaster would lead the tempo of pieces by lifting his or her bow in a rhythmic manner. Leadership might also be provided by one of the chord-playing instrumentalists playing the basso continuo part which was the core of most Baroque instrumental ensemble pieces. Typically, this would be a harpsichord player, a pipe organist, or a lutist or theorbo player. A keyboard player could lead the ensemble with his or her head, or by taking one of the hands off the keyboard to lead a more difficult tempo change. A lutenist or theorbo player could lead by lifting the instrument neck up and down to indicate the tempo of a piece, or to lead a ritard during a cadence or ending. In some works which combined choirs and instrumental ensembles, two leaders were sometimes used: A concertmaster to lead the instrumentalists and a chord-playing performer to lead the singers. During the Classical music period (c. 1720–1800), the practice of using chordal instruments to play basso continuo was gradually phased out, and it disappeared completely by 1800. Instead, ensembles began to use conductors to lead the orchestra's tempos and playing style, while the concertmaster played an additional leadership role for the musicians, especially the string players, who imitate the bowstroke and playing style of the concertmaster, to the degree that is feasible for the different stringed instruments.

In 1922, the idea of a conductor-less orchestra was revived in post-revolutionary Soviet Union. The symphony orchestra Persimfans was formed without a conductor, because the founders believed that the ensemble should be modeled on the ideal Marxist state, in which all people are equal. As such, its members felt that there was no need to be led by the dictatorial baton of a conductor; instead they were led by a committee, which determined tempos and playing styles. Although it was a partial success within the Soviet Union, the principal difficulty with the concept was in changing tempo during performances, because even if the committee had issued a decree about where a tempo change should take place, there was no leader in the ensemble to guide this tempo change. The orchestra survived for ten years before Stalin's cultural politics disbanded it by taking away its funding.

In Western nations, some ensembles, such as the Orpheus Chamber Orchestra, based in New York City, have had more success with conductorless orchestras, although decisions are likely to be deferred to some sense of leadership within the ensemble (for example, the principal wind and string players, notably the concertmaster). Others have returned to the tradition of a principal player, usually a violinist, being the artistic director and running rehearsal and leading concerts. Examples include the Australian Chamber Orchestra, Amsterdam Sinfonietta & Candida Thompson and the New Century Chamber Orchestra. As well, as part of the early music movement, some 20th and 21st century orchestras have revived the Baroque practice of having no conductor on the podium for Baroque pieces, using the concertmaster or a chord-playing basso continuo performer (e.g., harpsichord or organ) to lead the group.