Unlike the early Sonata No. 8, Pathétique, the Appassionata was not named during the composer's lifetime, but was so labeled in 1838 by the publisher of a four-hand arrangement of the work.
The Appassionata was considered by Beethoven to be his most tempestuous piano sonata until the Hammerklavier, being described as a "brilliantly executed display of emotion and music". 1803 was the year Beethoven came to grips with the irreversibility of his progressively deteriorating deafness.
An average performance of all three movements of the Appassionata sonata lasts about 23 minutes.
A sonata-allegro form in 12/8 time, the first movement moves quickly through startling changes in tone and dynamics, and is characterized by an economic use of themes.
The main theme, in octaves, is quiet and ominous. It consists of a down-and-up arpeggio in dotted rhythm that cadences on the tonicized dominant, immediately repeated a semitone higher (in G flat). This use of the Neapolitan chord (e.g. the flatted supertonic) is an important structural element in the work, also being the basis of the main theme of the finale. The rhythm of the theme is based on the Scottish folk song On the Banks of Allen Water. (British folk songs were well-known in Vienna at that time, and Beethoven, like Haydn, wrote many arrangements for British publishers.)
The second subject is a direct quotation of the first two lines of the folk song, re-hashed to fit the 12/8 time (the folk song is in 3/4). As in Beethoven's Waldstein sonata, the coda is unusually long, containing quasi-improvisational arpeggios which span most of the [early 19th-century] piano's range. The choice of F-minor becomes very clear when one realizes that this movement makes frequent use of the deep, dark tone of the lowest F on the piano, which was the lowest note available to Beethoven at the time.
The total performance time of this movement is about 10 minutes.
A set of variations in D flat major, on a theme remarkable for its almost crude simplicity. Its sixteen bars (repeated) consist of nothing but common chords, set in a series of four- and two-bar phrases that all end on the tonic. (See image.) The four variations follow:
Var. I: similar to the original theme, with the left hand playing on the off-beats.
Var. II: an embellishment of the theme in sixteenth notes.
Var. III: a rapid embellishment in thirty-second notes. A double variation, with the hands switching parts.
Var. IV: a reprise of the original theme without repeats and with the phrases displaced in register.
The fourth variation cadences deceptively on a soft diminished-7th chord, followed by a much louder diminished-7th that serves as a transition to the finale.
The total performance time of this movement is about 6 minutes.
Allegro ma non troppo
A sonata-allegro in near-perpetual motion in which, very unusually, only the second part is directed to be repeated. It has much in common with the first movement, including extensive use of the Neapolitan sixth chord and several written-out cadenzas. The movement climaxes with a faster coda introducing a new theme which in turn leads into an extended final cadence in F minor. According to Sir Donald Francis Tovey this is one of only a handful of Beethoven's works in sonata form that ends in tragedy.
The total performance time of this movement is about 7 minutes.
^ Schindler, A. (1970). Biographie von Ludwig van Beethoven. Reprografischer Nachdruck der Ausgabe Münster 1871. Georg Olms Verlag. p. 66