Composed 1781; 19 minutes

In the spring of 1781, hot on the heels of the successful premiere of Idomeneo in Munich, Mozart made a permanent move to the imperial city of Vienna. He was 25 and, on May 9, 1781, he broke with Archbishop Colloredo, dramatically abandoning the security of a court position. Now he would lead the largely uncharted life of a freelance composer. No longer the child prodigy, Mozart faced a new reality. His potential audience—and therefore his market—for chamber and solo keyboard music lay in the homes of the nobility and the growing public of amateur musicians. A little over a decade later, Beethoven would confront a similar challenge and chose a set of piano trios as his calling card. Mozart chose the ‘accompanied sonata’—music designed to appeal to players and patrons with the means to purchase and perform it at home.

When his six sonatas were published later that same year, the Viennese publisher Artaria announced them as “Six Sonatas for the keyboard with the accompaniment for a violin by the sufficiently well-known and celebrated Herr Wolfgang Amadee Mozart.” They were an immediate success. The collection also helped spread the mature Mozart’s reputation further afield. In Hamburg, Carl Friedrich Cramer’s widely read Magazin der Musik reviewed them warmly: “These sonatas are the only ones of their kind. They are rich in new ideas and show traces of the very great musical genius of their author. Very brilliant and very well suited to the instrument. Moreover, the violin accompaniment is so ingeniously combined with the keyboard part that both instruments are kept in equal prominence. And so these sonatas call for a violinist as skilled as a keyboard player.”

The first movement of K. 380 in E-flat major is broad and commanding in scope. Its keyboard writing is brilliant, at times almost concerto-like. The violin engages in energetic dialogue as the instruments exchange thematic material and jointly shape the musical argument. Moments of expressive harmonic piquancy point toward Mozart’s later Viennese style. The Andante in G minor is reflective and lyrical. Its quietly expressive minor-major shading encloses a second theme that seems an extension of the first—heard initially in the major before returning in the somber minor, all within a compact sonata-form. The Rondo finale brings a sparkling, playful close, restoring the sonata’s buoyant E-flat world after an inward middle movement.