Unlike the dynamics of the early baroque, Classical music dynamics tended to be a little more diverse, yet without the passion of the Romantic era. There was the range, from the pianissimo to the fortissimo but music of the early Classical era, in which Mozart wrote this piece, lacked the dramatic and sudden changes characteristic of later Classical composers such as Beethoven, who led into the Romantic.
In the first subject of the exposition, the dynamics are at their most basic, quiet, loud or suddenly loud. An example of these three dynamics can be shown at the beginning itself and after when the entire orchestra has joined in. In the transition section, however, the dynamics stay at forte and later at bar 34 increases to sforzando. This dynamic is contrasted in the second subject where it begins at bar 44 as piano where it stays until there is a crescendo at bar 63 and ends up as forte at bar 64. This is to stay until the end of the second subject where it finishes strong and loud. The codetta, the ending of the exposition, begins at bar 73 as a very soft which will contrast the strong forte ending at the end, at bar 100. The development section is similar to subject one being quite, loud and suddenly loud. However, at bar 162 onwards, there is use of mezzo forte-piano, indicating a moderately loud dynamic before instantly diminishing to a much softer volume.
The first subject of the recapitulation, adopts the dynamics of subject one in the exposition, which were the basic dynamics; piano, forte and sforzando. The bridge, or transition passage, is an overpowering section with loud dynamics. The second subject, as well, adopts similar dynamics to the relative subsection in the exposition. The coda starts off as forte in bar 293 and maintains this until the end of the passage.
The exposition is introduced in its home key of G minor. However, from bar 22, F♯ has been dropped and the key starts to move towards relative major key of B♭major. This key has been held until the end of the codetta where the end note has returned to the key of G minor. However, in between, there was been several chords that are played. For example, at bar 49, there is use of the circle of fifths, where the key has progressed from G7 to C to F7 to B♭, despite still maintaining in the key of B♭major. Also to note in bar 63, a diminished seventh chord (E, G, B♭and D♭) were played along in the bass part.
The development section however, contains the most key changes of all sections. There is a falling semitones from G minor (the home key), to G♯ (which is played in its diminished seventh chord) to F♯ minor, F (E♯) and finally D♯. These falling semitones are marked in the bass part. Even after these numerous key changes, the development section is still continues to explore the first subject with different key changes and the most important circle of fifths that span from bar 114 to 128. Starting from E minor, the key then changes to A minor, and continues to move in fourths to D minor, then G minor, to C major, F major and finally B♭ major.
There is no major key changes in the recapitulation section, however, as the key once again returns to the home key of G minor. However, the second subject in the recapitulation section has a section in which the music modulates to E flat major. However, this is temporary and the music soon returns to the home key of G minor. It is interesting to note that the final homophonic reiteration of a series of chords I and V in G minor ending with four emphatic full stops (G minor chords). The last section of six bars corresponds to the last six bars of the exposition and the section is rounded off with a perfect cadence in G minor at bars 275-276.
Mozart originally scored the work without the recently invented clarinets, although he later wrote another version which included two clarinets. Another interesting fact is that Mozart is modest in the instrumentation that he uses in his work, which only requires seven woodwind players (one flute, two oboes, two clarinets and two bassoon) and from the brass section, two horns - one in B flat and one in G. This is to give him the notes G-B flat-D (G minor tonic chord) and B flat-D-F (B flat major tonic chord). Of more significant note is the fact that Mozart does not use trumpets or drums, which was very unlike the typical Classical-era sonata.
The woodwinds in the exposition section are rarely of any significance, except to provide a chordal accompaniment to the violins, which were playing the melody. However, during the second subject, they began to share parts of the melody with the stringed instruments and later at bar 52, the roles of the stringed and woodwinds were reversed. Despite playing alongside the violins at the end of the codetta, their role only increased during the development section.
Right at the beginning of the development section, at bar 102, the woodwinds provide a link in order for the violins to be able to change keys. Their next role in the development section was to explore the first section, whilst the string instruments provide the contrapuntal texture. This is later reversed. Again, at bar 124, the woodwinds once again provide the chordal accompaniment to the string instruments. The use of imitation between the violins and the woodwind are seen in bars 138 to 141 and again in bars 143 to 145.
The final recapitulation is similar to the exposition in terms of the use of woodwind instruments. It is however interesting to note that the three-note motif from the first subject is passed between the clarinet, bassoon and flute, whilst the first violins exchange the first two notes of the motif in augmentation with the violas and cellos.