Mozart’s Piano Sonata Number
The first movement of Mozart’s Piano Sonata Number 13, was composed at the end of 1783 and published in 1783. This piece is playful yet structured. It is full of dexterity and complexity but still manages to be both accessible and organized. It also reflects Mozart’s admiration of and influenced by Johann Christian Bach, a musical peer of Mozart’s who died in 1782. Most musical scholars familiar with both composers agree that the opening pattern of Sonata Number 13 has a flattering similarity to JC Bach’s Op. 5 no. 3 and Op. 17 no.4 piano sonatas. Another influence dual source is the style of the concertos of the time, grandiose and buoyant in style. The first movement contains numerous concerto like embellishments that stray from a standard sonata, this adds an element of boldness to the piece.
As far as piano sonatas go, no. 13 is fairly textbook in its construction. The foundation of the sonata structure is the contrast, comparison, and unification, of two musical keys. These two keys are known as the ‘tonic’ and ‘dominant’ of a piece. The sonata establishes these two themes in an exposition section, followed by a development section which, follows the establishment of the second key. The tonality is deconstructed and its musical component segments are modified, explored, and expanded. At the end of the development section, the piece returns to the tonic key in order to summarize the material from the exposition.
The sonata, in general, is inherently a fascinating exercise in ‘voice leading,’ or the way in which individual music parts, interact to form each chord progressions. Individual composers were known for their particular voice-leading styles, as each possessed particular habits when it came to transitioning from chord to chord within progressions or entire pieces. The particular rules of the sonata were challenges that gave composers, like Mozart, the opportunity to show their voice-leading creativity.
Mozart’s piano sonata number 13 is written in simple quadruple meter and is in the key of B-flat major. Measures 1-10 present the tonic key, which supports that this piece is in B-flat major. Measures 1-63 consist of the exposition of the sonata. Measures 64-93 consist of the development of the sonata. Measures 94-165 consist of the recapitulation of the sonata. In measure 10 there is a restatement of the opening piece played an octave lower. In measure 12 there is an E natural, this note introduces a C-major harmony which places the transition to the dominant key of F major. In measures 13-15 there are a group of sixteenth notes descending, this illustrates the playfulness of this piece. In measure 17 there is a B-natural, which returns the piece back to the tonic key of B-flat major. In measure 22-30 the key is changed back to F major. Measure 64 is the beginning of the development section. The eighth note rhythmic triads played in measure 1 reappear and are added upon between measures 64-70. In measure 87-90 the key changes back to the tonic key of B-flat major. Measures 94-105 begin the recapitulation. Measures 22-30 and 119-143 feature the same musical idea, except that measures 119-143 are in the tonic key. Measure 152-165 are made up of the coda, which is mostly a duplication of measures 50-63 of the exposition.
Mozart is true to the stylistic requirements of the genre without deviating from the overall structure of a sonata while being creative by changing between the two keys. Furthermore, Mozart’s voice-leading technique is bold and enhances the piece’s complexity. The tempo Mozart utilizes is surprisingly brisk given the balancing required by the composition.