Between the thirteenth and seventeenth centuries the term sonata, from the Italian “to sound”, had no precise meaning when applied to music. Depending on where and when it was used, it could imply a collection of dance pieces; a lute work; a work for one or more solo instruments with or without accompaniment; and in some cases even a vocal work. During the Baroque period it most commonly referred to the trio sonata: a chamber piece, usually with multiple movements, in which two melody instruments are supported by one keyboard and one bass instrument. They could be religious, the Sonata da chiesa, or secular, the Sonata da camera. But the term is also found at the top of Baroque solo pieces – such as Bach’s for violin – which could just as easily be referred to as suites or partitas. In the mid-1700s, the transition to the Classical era, the term was increasingly associated with works for solo keyboard. Domenico Scarlatti, who wrote over 500 sonatas for harpsichord, was a major figure in this development, as was C.P.E. Bach, whose sonatas for the clavichord (a forerunner of the piano, see p.472) were especially significant because he usually adopted a pattern of three movements, arranged fast-slow-fast. It was this model that was taken up by Haydn and Mozart, and later by Beethoven. The latter is particularly important for the way he developed what was a sophisticated and essentially elegant genre into something symphonic in its proportions and emotional weight. Most sonatas from the Classical period onward are written almost exclusively for solo piano or for a piano and one other instrument (such as violin or cello) and usually conform to the three-movement fast-slow-fast plan (one critic declared that in the first movement composers showed what they could do, in the second what they could feel, and in the third how glad they were to have finished). Mozart rarely deviated from this pattern, but Haydn and Beethoven regularly inserted an extra movement before the finale (either a minuet or a scherzo) and both wrote a few two-movement sonatas. It’s not just the pattern of movements that defines a Classical sonata, though; it’s the way the individual movements are written. The first movement (and sometimes other movements) generally follows a structure known as sonata form. Confusingly, though, this term doesn’t only refer to sonatas: most symphonies and chamber music of the Classical era (and much later music) make use of sonata form, especially in the first movement, hence the alternative phrase, first movement form. In the most basic terms, sonata form is a three-part scheme, consisting of an exposition, in which the thematic material is introduced, a development, the dramatic heart of the piece where the themes are further explored by the composer, and the recapitulation, an altered restatement of the exposition. As well as a way of approaching themes, though, sonata form is a way of approaching tonality and the relationship between keys. The exposition usually contains two groups of themes, separated by a transition; the first is sounded in the home key (the key the piece is “in”), and the second is in another key. In the development section, various keys are visited, adding to a sense of drama and instability, and the recapitulation usually repeats the material of the exposition, but plays both theme groups in the home key, providing a sense of finality and closure. This form is true of most Classical sonatas, but it is not a strict set of rules – it was the works that defined the genre, not the genre that defined the works. Though its heyday as the Classical era, the sonata was carried forward by Romantic composers such as Schubert, Chopin, Schumann, Liszt and Brahms, though only the latter firmly maintained the principles of sonata form. The twentieth century, too, yielded its fair share of sonatas – Debussy, Bartók, Shostakovich, Cage and Carter are just a few of the composers who reworked the genre in a modern style.

Complete Piano Sonatas: Goode (Elektra Nonesuch; 10 CDs).
Richard Goode’s cycle is at its best with the late sonatas, which are available in a separate box. The middle-period works sometimes suffer from a percussive, over-weighted strength, while the early sonatas suggest that Goode is happier with introspection than with humour. Still, this superbly recorded and annotated set is a personal and revealing cycle that can stand up to any of the competition.

Complete Piano Sonatas: Perl (Arte Nova; 10 CDs).
Alfredo Perl is a young Chilean pianist with an amazing technique and plenty of passion. He never shies away from the weird and quirky aspects of Beethoven and is especially strong in the most turbulent sonatas, like the Appassionata. Occasionally the more lyrical and introspective moments evade his grasp, but in the end the sheer energy of his playing sweeps you away. A real bargain.

Complete Piano Sonatas: Kempff (Deutsche Grammophon; 8 CDs). Mono sound, but Kempff’s 1950s set of the complete sonatas is still one of the finest ever recorded. The lucidity and intensity of his concerto recordings are both present, but now there’s an added edge of directness – as though you’re listening to something acutely relevant and confidential. It’s most telling in the great slow movement of the Hammerklavier, or the variation-finales of Opp. 109 and 111, yet Kempff can also sparkle and soar, as in the finale of Op. 2, No. 3.