Mozart Completes “Dissonance” String Quartet No. 19 in C Major (K. 465)

Wolfgang Amadeus Mozart completed his String Quartet No. 19 in C major, K. 465, the final work in the set of six quartets dedicated to Joseph Haydn. Although commonly associated with 1784 due to the broader composition period of the set, Mozart dated the autograph of K. 465 on 14/01/1785 in Vienna. The quartet was later published in 1785 together with the other Haydn quartets. It soon became known by the nickname “Dissonance” because of its unusual slow introduction, which opens with harmonically ambiguous chords and chromatic lines that depart from typical Classical conventions. The introduction begins with sustained tones and shifting harmonies that create tension before the main Allegro in C major begins. Early listeners found the opening striking, and some musicians initially suspected engraving errors when the work was first circulated. The harmonic writing includes suspended dissonances, chromatic motion, and delayed tonal resolution. After this introduction, the quartet proceeds into a more conventional sonata form movement, followed by an Andante cantabile, a minuet and trio, and a final Allegro molto. The contrast between the unsettled opening and the clear tonal writing of the Allegro contributed to the work’s distinctive reputation. String Quartet No. 19 concluded Mozart’s six quartets dedicated to Haydn, composed between 1782 and 1785. Mozart presented the set to Haydn, who later commented favorably on the works in a well known statement addressed to Leopold Mozart. The “Dissonance” quartet, as the final entry in the series, demonstrates expanded harmonic experimentation within the established string quartet format and was published in Vienna in 1785. Why This Moment Matters The completion of K. 465 on 14/01/1785 closed Mozart’s Haydn quartets with a work noted for its unconventional harmonic opening, which led to its later “Dissonance” nickname.