Fantasia in C minor, K.475 (1785)

Adagio - allegro - andantino - più allegro - tempo I

Although the Fantasia in C minor was first published with the Piano Sonata in C minor under the same opus number – Artaria issued them as “Opus XI” in Vienna in 1785 – both works are complete in themselves. The Sonata was written in October 1784 and the Fantasia seven months later, a time gap which suggests that they were not actually conceived as companion pieces. While the Fantasia makes a highly effective introduction to the Sonata, as Mozart was obviously aware, it is quite possible that it originated in some other circumstances – perhaps as an improvisation at one of Baron von Swieten’s Sunday lunchtime baroque-revival concerts. Certainly, it begins with a stylistic allusion to J.S. Bach, in his chromatic Musical Offering kind of mode, even though its Viennese classical identity is unmistakably established within just a few bars. A spontaneously motivated construction, recalling the opening Adagio material as if by chance at the end, the Fantasia in C minor anticipates more than a little of the dramatic and the harmonic inspiration Beethoven was to find in the same key.

Adagio - allegro - andantino - più allegro - tempo I

Sonata in C minor, K.457 (1784)

Molto allegro

Adagio

Allegro assai

The Fantasia in C minor and the Sonata in C minor were written at different times - the Sonata first in October 1784, the Fantasia seven months later - and were listed separately in Mozart’s catalogue of his works. When they were first published, however, in Vienna in 1785, Artaria issued them together as “Opus XI,” and they are often performed that way even now, as a mutually enhancing pair of works cast in the same key but shaped according to very different structural principles.

The Fantasia does, in fact, make a highly effective introduction to the Sonata, even though it probably originated as a quite separate piece - perhaps as an improvisation at one of Baron von Swieten’s Sunday lunchtime baroque-revival concerts. Certainly, it offers a stylistic allusion to J.S. Bach, in his chromatic Musical Offering kind of mode, in the few bars before it so unmistakably establishes its Viennese classical identity. A spontaneously motivated and harmonically liberated construction - recalling the opening Adagio material as if by chance at the end - the Fantasia in C minor anticipates more than a little of the dramatic harmonic inspiration Beethoven was to find in the same key.

There is no doubt that the Sonata in C minor - the first work of the kind that Mozart had completed in six years - is worthy of such an introduction. He had not abandoned the keyboard: the three Concertos K.413-5 are ample evidence of that. But when he returned to the piano sonata it was as though he had rediscovered not only the form but also the instrument. Perhaps the truth is that it was not until now, after the experience of the concertos, that he had learned how to exploit the new possibilities of the Stein pianoforte which he had first played and so much admired in Augsburg in 1777.

The Sonata is fascinating too for the profound impression it clearly made on Beethoven. Just as the Concerto in C minor K.491 was to have an immediate effect in Beethoven’s own Piano Concerto in the same key, so the Sonata in C minor K.457 echoes throughout Beethoven’s early sonatas, particularly the two in C minor Op.10 No.1 and the Pathétique Op.13. The triadic outline of the first subject of Mozart’s opening Allegro is not unconventional, it is true, and nor is the modulation to the relative major for the second subject. But the short development - beginning in C major and plunging dramatically into F minor - is an inspiration which Beethoven faithfully imitated in his Op.10 No.1.

As for Mozart’s enterprise in exploiting the Viennese pianoforte, the slow movement offers numerous examples. Structurally, this Adagio resembles nothing more adventurous than a set of variations. But between the several reappearances of the opening melody, with a different decorative surface each time but always in E flat major, there are interludes of considerable harmonic and colour interest - the repeated quiet staccato on top F (at that time the very top note of the keyboard), the note-by-note alternation of forte and piano contradicting the rhythmic accents, the little cadenzas, the legato broken chords, the quiet repeated staccato at the other end of the keyboard.

The very lowest note of the piano as Mozart knew it is featured in the Molto allegro - an extraordinarily bold rondo of abrupt modulations and changes of temperament, punctuated by pauses and silences and oddly coloured by the right hand’s fascination for the extreme low notes of the keyboard.