Mozart’s Sonata No. 6 in D major, K. 284, opens with an Allegro built from bright chordal statements, quick runs, and sharply contrasted answers. The piano frequently moves from full, accented gestures to lighter writing, with the right hand’s melodic figures supported by repeated notes or broken chords. The movement’s large sections bring these ideas back in altered surroundings, and both principal sections carry repeat signs in this score.

Opening section: A strong chord launches a rapid figure shared by the hands, followed by a shorter, detached reply. Running sixteenth notes and pairs of upper notes alternate with quieter phrases. The left hand supplies an active foundation through repeated eighth notes, bass notes, and broken-chord patterns. Sudden changes in dynamics make the exchanges between the statements and answers especially clear.

Contrasting material and first close: A softer, dotted melodic idea appears above repeated accompaniment notes and chords. Trills lengthen important upper notes while the bass continues moving below. The closing passages combine dotted figures, parallel runs, and a longer trill before the first section repeats.

Middle section and return: Continuous upper runs pass through changing harmonies, and accented leaps interrupt the smoother lines. Lower broken chords support the sequence until the opening gesture returns. The familiar secondary material follows, now leading into an expanded closing stretch with further running figures and cadential trills. The final repeat returns to the beginning of this larger second section.

Interesting fact: The opening repeatedly places bold chordal gestures beside light, detached answers. This contrast is visible not only in the notes, but also in the score’s closely spaced changes of dynamics and articulation.