Sinfonia concertante

Sinfonia concertante (IPA: [siɱfoˈniːa kontʃerˈtante]; also called symphonie concertante) is a mixture of the symphony and the concerto genres. It is a concerto in that soloists are on prominent display, and a symphony in that the soloists are nonetheless discernibly a part of the total ensemble and not preeminent. It emerged as a musical form during the Classical period of Western music.

In the Baroque period, the differences between a concerto and a sinfonia (also "symphony") were initially not all that clear. The word sinfonia would, for example, be used as the name for an overture to a stage work. Antonio Vivaldi wrote "concertos" which did not highlight individual soloists and which were stylistically more or less indistinguishable from his "sinfonias." The Baroque genre that comes closest to the Classical sinfonia concertante is the concerto grosso; among the most famous of these are those by Arcangelo Corelli and George Frideric Handel.

By the Classical period (roughly 1750-1800), both the symphony and the concerto had acquired more definite meanings, and the concerto grosso had disappeared altogether. This led in the last decades of the 18th century to attempts to combine the two genres, such as those by composers of the Mannheim school. Johann Christian Bach (the so-called "London Bach" and youngest son of Johann Sebastian) was publishing symphonies concertantes in Paris from the early 1770s on. Mozart, acquainted with the Mannheim school from 1777 and probably aware of J.C. Bach's publications, put considerable effort into attempts to produce convincing sinfonie concertanti. His most successful are the following:

...
Wikipedia