The Piano & the Piano Sonata

     During this period the harpsichord was gradually dying out, and the piano was gaining the ascendancy.  The sustaining pedal was invented, the range was extended, the instrument developed greater sonority, and it became very popular.

    All the four chief Viennese composers, Haydn, Mozart, Beethoven and Schubert, wrote sonatas for the piano.  Mozart's and Beethoven's form an essential part of the pianist's repertory, and many people gain their first impression of the difference between Mozart's and Beethoven's styles through a study of their sonatas.  

    Haydn developed the sonata from what he found in the works of C. P. E. Bach, though in his case it is the development of sonata form, rather than his actual keyboard compositions, that are important, and most of them were probably still played on the harpsichord.  He simplified the contrapuntal style of his predecessors, and wrote melodic, clearly defined subjects.  His sonatas usually have two or three movements; and when there are three the middle movement is more often an adagio than a minuet, though the last movement is then usually a dance form such as a minuet with variations or a rondo.

    Mozart's 24 sonatas are of rather unequal merit, and many of them are early works.  They are almost invariably in three movements, the usual plan being an allegro in sonata form, a slow movement, and a rondo.  In addition, he wrote a number of isolated sonata movements, and other piano works such as variations, rondos and fantasies.  But his piano writing is seen at its best in his piano concertos.  In Mozart's time the piano had a light and delicate touch; but Beethoven required greater sonority, and encouraged this development with piano manufacturers.

    Beethoven's 32 sonatas are a most important side of his work.  They are longer, more dramatic and more passionate than Mozart's, and bear evidence of his development through the "three periods" of his life.  He writes magnificent development sections and long codas, and his transitions are an integral part of the movement, instead of the rather obvious punctuation points that often occur in Mozart's sonatas.  The four-movement plan is common, the additional movement frequently being a scherzo.  But Beethoven experiments with the number and order of his movements.  Everyone knows his so-called 'Moonlight' sonata, which begins with a slow movement.  Other famous sonatas are the 'Pathétique', the 'Waldstein' and the 'Appassionata'.  He also wrote several fine sets of variations for the piano.  

    Schubert's 22 sonatas have occasional weaknesses, such as an unpianistic layout, but they contain some lovely movements, with beautiful and unexpected but delightful modulations.  His impromptus and Moments Musicaux are popular examples of his other works for piano.