Double concerto

A double concerto (Italian: Doppio concerto; German: Doppelkonzert) refers to two distinct variations on the concerto. Most often, it refers to a concerto featuring two performers, as opposed to the usual single performer, in the solo role. These two performers' instruments may be of the same type, as in Bach's, Concerto for Two Violins, or different, as in Brahms's Concerto for Violin, Cello and Orchestra.

The term may also be used to refer to the use of a double orchestral body where the work is in concerto grosso form; for example, Martinů's Double Concerto for Two String Orchestras, Piano, and Timpani is commonly known by the title "Double Concerto," where the word "double" refers to the two string bodies rather than to the piano and timpani who are not soloists in the conventional sense.

Concerti with more than two solo parts may be known by the terms "triple concerto" (Italian: Concerto triplo, German: Tripelkonzert), "quadruple concerto," etc., but not usually when the instruments of the same type (e.g., Vivaldi's Concerto for Four Violins in B minor, catalogued as RV 580 and transcribed for four harpsichords by Bach as BWV 1065).

One common arrangement for a triple concerto is for violin, cello, and piano, Beethoven's Triple Concerto for Violin, Cello, Piano and Orchestra being perhaps the most notable, but there have been many; see the list of triple concertos for violin, cello, and piano.

A notable quadruple concerto is Olivier Messiaen's incomplete Concert à quatre.

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