In origin, sonata referred to music that was 'sounded', not 'sung'. But in the eighteenth century it was applied to a particular form of composition that came to dominate almost all instrumental music. Sonata form occupies a central place in the work of the classical composers from Haydn to Mahler. It is to be contrasted with the polyphonic style of the preceding era; and it embodied the conventions against which later 'modern' styles were to react. It has two aspects - the division of compositions into a formal sequence of movements and the elaboration of homophonic harmony.

Sonata form had no single starting point. An early manifestation was Gabrieli's Sonata pian e forte (1597) for violin, cornett, and six trombones. But its codification into four set movements did not occur until the work of Arcangelo Corelli (1653-1713) of Bologna. It was developed in the keyboard compositions of C.P.E. Bach (17814-1788), and was brought to perfection by Haydn and Mozart. Its theoretical foundations were foreshadowed in J.P. Rameau's Traite d'harmonie(1722), but were not fully expounded until Carl Czerny's School of Practical Composition(1848), twenty years after the death of its greatest exponent - Beethoven.

Conventional sonata form divides the musical work into four contrasting movements. The opening Allegro, in fast tempo, has parallels with the operatic overture. The slow second movement grew out of the Baroque aria da capo. The third movement, usually minuet and trio, was based on the dance suite. The finale returns to a key and tempo reminiscent of the opening. Each of the four movements follows a standard pattern consisting of the exposition of the melodic subjects, their harmonic development, and , at the end their recapitulation, sometimes with a related coda or 'afterthought'.

Homophony is the opposite of polyphony,. It is characterized by music based, , like hymn tunes, on a progression of chords, whose constituent notes do note possess either melodic or rhythmic independence. Classical harmony, therefore, is the opposite of polyphonic counterpoint. The scene of J.S. Bach composing he 'Art of Fugue' (1750) in an empty church in Leipzig symbolizes the passing of the polyphonic era. The scene of Beethoven, weary but sublimated, struggling to complete his five last quartets, may be taken as the summit of homophony.

Beethoven considered hisQuartet in C sharp minor, Opus 131(1826), to be his finest work. In it, he expounds each of the elements from which the sonata form had grown- an opening fugue; a single theme scherzo;a central aria with variations; and a 'sonata within a sonata' on the inverted fugue. It has been called 'a cycle of human experience', and 'a microcosm of European music'. In the span 1750 to 18927, Haydn, Mozart, and Beethoven composed between them over 150 symphonies, over 100 piano sonatas, over 50 string quartets, and numerous concertos - all in sonata form. These works form the core of the classical repertoire.

History of Music
Portrait Gallery
Glossary of Musical Terms
Classical Midi Connection