A Musical Joke (in German: Ein musikalischer Spaß) K. 522, (Divertimento for two horns and string quartet) is a composition by Wolfgang Amadeus Mozart; the composer entered it in his Verzeichnis aller meiner Werke ('Catalogue of all my Works') on June 14, 1787. The music is intentionally written to be funny, being liberally sprinkled with obtrusively clumsy, mechanical and over-repetitive composition, together with passages evidently designed to mimic the effects of inaccurate notation and inept performance. Commentators have opined that the piece's purpose is satirical—that "[its] harmonic and rhythmic gaffes serve to parody the work of incompetent composers" -- though Mozart himself is not known to have revealed his actual intentions.
the use of discords in the French horns, satirizing the incompetence of the copyist, or the hornist grabbing the wrong crook,
use of a whole tone scale in the violinist's high register, probably in order to imitate the player's floundering at the high positions
The piece is also notable for the earliest known use of polytonality, creating the gesture of complete collapse with which the finale ends. This may be intended to produce the impression of grossly out-of-tune string playing, since the horns alone conclude in the movement's tonic key: the lower strings behave as if the tonic has suddenly become B flat, while the violins and violas switch to G major, A major and E flat major respectively:
Some theorists believe that A Musical Joke is a parody of works by clumsy composers of Mozart's time. With such an assumption, one might find some points of the score humorous, such as the more elementary developments of the theme, where the poor composer might feel the agony that he/she had to proceed with the development. Other theorists disagree with that view, saying that perhaps Mozart used parody and comedy as an excuse to try things that at the time were not in practice; the piece would then be intended in a more serious tone than so advertised but only for the composer himself.
The use of asymmetrical phrasing, whole-tone scales, and multitonality is quite foreign to music of the classical era. However, these techniques were later revisited by early 20th century composers like Claude Debussy and Igor Stravinsky, who were searching for a new musical language. In this later context, these conventions were seen as legitimate new techniques in serious music. In Mozart's time, however, these non-classical elements give the piece its comedy and express the composer's sense of musical humor.
Remarkably, A Musical Joke is the first piece entered in Mozart's list of works following the death of his father Leopold on May 28.
Issues of Translation
The established English title A Musical Joke is a poor rendering of the German original: as Fritz Spiegl pointed out, 'Spaß' does not strongly connote the jocular—for which the word 'Scherz' would normally be required. In Spiegl's view, a more accurate translation would have been Some Musical Fun.