A report on Choir, Musical ensemble and Orchestra

A choir (also known as a chorale or chorus) is a musical ensemble of singers.

Some music ensembles consist solely of instrumentalists, such as the jazz quartet or the orchestra.

Other music ensembles consist solely of singers, such as choirs and doo wop groups.

Choirs may sing without instrumental accompaniment, with the accompaniment of a piano or pipe organ, a small ensemble, or an orchestra.

The Ninth asks for a second pair of horns, for reasons similar to the "Eroica" (four horns has since become standard); Beethoven's use of piccolo, contrabassoon, trombones, and untuned percussion — plus chorus and vocal soloists — in his finale, are his earliest suggestion that the timbral boundaries of symphony might be expanded.

Orchestras, choirs, concert bands and other sizable musical ensembles such as big bands are usually led by conductors.