String Quintet (Schubert) No. 3 in C major, K. 515 and Beethoven's String Quintet, Op. 29 in C major. According to Charles Rosen, the opening theme of Schubert's work emulates many characteristics of the Mozart quintet's opening theme, such as decorative turns, irregular phrase lengths, and rising staccato arpeggios (the latter appear only in Schubert's recapitulation). But whereas the string quintets of Mozart and Beethoven are composed for a string quartet augmented by a second viola, Schubert adopts a somewhat unconventional instrumentation, employing two cellos instead of two violas, creating richness in the lower register. Before Schubert, Luigi Boccherini had replaced the second
String quintet a double bass, and Mozart's famous "Eine kleine Nachtmusik" may be performed with this instrumentation (the double bass being optional). Alternative additions include clarinet or piano (see clarinet quintet, piano quintet); and other closely related chamber music genres include the string quartet (much more common), the string trio, and the string sextet. A more unusual form of string quintet is the "violin quintet" composed of 3 violins, a viola and a cello (thus a string quartet with an additional violin). The term "string quintet" may refer to a group of five players that performs such works. The ensemble was standard