Wolfgang Amadeus Mozart
Divertimento in B flat major KV 137

Two pieces for string quartet: in D major, in B flat major and in F major (KV 136-138), were written in early 1772. Alfred Einstein maintains that it was not Mozart who defined them as divertimentos – that the composer “wrote them before his last trip to Italy just in case someone wanted him to write a symphony; then he would add a winds part in the first and the last movements, but otherwise would be free to work on his opera Lucio Silla.”
This would have been unthinkable fifteen years later. Yet at the time, there were still similarities between the emergent genres of instrumental music. In the middle of the 18th century, the symphony ousted the suite, and the features of both cyclic forms found their use in serenades. These, first performed outdoors, entered concert halls as pieces of less rigorous form than that of symphony. Divertimentos, on the other hand, were a novelty from the very start treated as “easy listening.” They, too, acquired some traits of the suite and the symphony and became hardly discernible from serenades, with their four to ten parts, simple form and straightforward texture. The popularity of this music is best illustrated by the plain fact that Mozart alone wrote more than twenty divertimentos and serenades. When, in 1787, he wrote his last – Eine kleine Nachtmusik (KV 525) – it still had the features of the old-style symphony. His Prague Symphony (KV 504) of the same year belonged to the entirely different world of works unique in their form and expression.
Einstein was probably right when he took these three-movement “quartets” for “symphonic sketches. Whether this is true or not, Divertimento in B flat major KV 137 sounds like a symphony for strings with no first movement and a different of the other parts – as if for effect.
∙ Movement One (Andante) seems to begin “from the middle” after the manner of a recitativo e arioso, with its typical two-part form. Yet its character is purely instrumental.
∙ Movement Two (Allegro di molto) might suggest that, at 16, Mozart was familiar with Haydn’s latest works. This impressive composition is almost as robust as finales in symphonies of the Eisenstadt master. It has a similar main outline and type of narration; on the other hand, melodics, ornamentation and tone are unquestionably Mozart’s.
∙ Movement Three (Allegro Assai) has all features of a minuet, yet a trio has been replaced with two occurrences of a canon-initiated episode where the melody suddenly breaks down and moves in G minor among measure-obliterating syncopes. Each return of the main idea ends in a ländler phrase which drowns in silence at its third appearance, closing the piece in a moment as quizzical as that of it beginning.

Wiesława Berny-Negrey