Estructura en tres parts que apareix en el primer moviment de sonates, simfonies i quartets
https://en.wikipedia.org/wiki/Sonata_form
Introducció
Exposició, primer tema: First subject group, P (Prime) – this consists of one or more themes, all of them in the tonic key. Although some pieces are written differently, most follow this form.
Segon tema [ (D major) of Haydn’s Sonata in G Major, Hob. XVI: G1, I, mm. 13–16.].
- Transition, T – in this section the composer modulates from the key of the first subject to the key of the second. If the first group is in a major key, the second group will usually be in the dominant key. However, if the first group is in minor key, the second group will usually be the relative major.
- End of second subject and Codetta (D major) of Haydn’s Sonata in G Major, Hob. XVI: G1, I, mm. 17–28
- Second subject group, S – one or more themes in a different key from the first group. The material of the second group is often different in rhythm or mood from that of the first group (frequently, it is more lyrical).
Codetta, K – the purpose of this is to bring the exposition section to a close with a perfect cadence in the same key as the second group. It is not always used, and some works end the exposition on the second subject group.
DEVELOPMENT
RECAPITULATION
- First subject group – normally given prominence as the highlight of a recapitulation, it is usually in exactly the same key and form as in the exposition.
- Transition – often the transition is carried out by introducing a novel material: a kind of an additional brief development. It is called a “secondary development”.
- Second subject group – usually in roughly the same form as in the exposition, but now in the home key, which sometimes involves change of mode from major to minor, or vice versa, as occurs in the first movement of Mozart’s Symphony No. 40 (K. 550). More often, however, it may be recast in the parallel major of the home key (for example, C major when the movement is in C minor like Beethoven’s Symphony No. 5 in C Minor, op. 67/I). Key here is more important than mode (major or minor); the recapitulation provides the needed balance even if the material’s mode is changed, so long as there is no longer any key conflict.