Wolfgang Amadeus Mozart's Clarinet Quintet, K. 581, was written in 1789 for the clarinetist Anton Stadler. A clarinet quintet is a work for one clarinet and a string quartet. Although originally written for basset clarinet, in contemporary performances it is usually played on a clarinet in A. It was Mozart's only completed clarinet quintet, and is one of the earliest and best-known works written especially for the instrument. It remains to this day one of the most admired of the composer's works. The quintet is sometimes referred to as the Stadler Quintet; Mozart so described it in a letter of April 1790. Mozart also wrote a trio for clarinet, viola and piano for Stadler, the so-called Kegelstatt Trio, in 1786.
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