The String Quintet No. 2 in C minor, K. 406/516b, was written by Wolfgang Amadeus Mozart in 1787. Like all of Mozart's string quintets, it is a "viola quintet" in that it is scored for string quartet and an extra viola. Unlike his other string quintets, however, the work was not originally written for strings. Having completed the two string quintets K. 515 and K. 516, Mozart created a third by arranging his Serenade No. 12 for Winds in C minor K. 388/384a, written in 1782 or 1783 as a string quintet. Although by then Mozart was entering each new work into his catalogue of compositions, he did not enter this quintet, perhaps because it was an arrangement rather than a new work.
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