Rondo in F for 2 horns, 2 violins, viola and basso

Mozart referred to a small number of works for strings alone, or for strings, horns, and occasionally another woodwind instrument, as *Divertimento* or *Notturno*. The number of movements varies, ranging from three to six. According to 18th-century performance practice, these pieces require only one player per part, in contrast to serenades and cassations, which were typically performed with an orchestra. The most famous works of this kind are A Musical Joke, K. 522 (with 2 horns) and Eine kleine Nachtmusik, K. 525 (for strings) from Mozart’s Vienna period. Musically, the three Divertimenti K. 136–138 are barely distinguishable from the early string quartets K. 155–160. K. 247, K. 287, and K. 334 form a distinct group of sextets featuring a highly virtuosic first violin part.