, Opus 90 and 142 (post.), are a series of pieces for solo piano composed in 1827 and first published during the composer's lifetime (or shortly thereafter) under that name. There are eight such Impromptus in total.
Three other unnamed piano compositions, written in May 1828, a few months before the composer's death, are alternatively indicated as Impromptus or Klavierstücke ("piano pieces").
Four Impromptus, Op. 90 (D. 899)
The Opus 90 impromptus consist of 4 typical Romantic-era pieces, each with distinct elements.
No. 1 in C minor
The first Impromptu, written in C minor, commences with a chord of octaves in G, leaving the key of the piece ambiguous. The piece continues into a march-like melody written in C minor (where the true key is revealed). The march theme is embellished, then winds slowly into the key of A-flat major, where a new melody is introduced and contrasts the beginning section with its songlike melody, accompanied by triplets in the bass. Upon returning to the main theme the first time, it has combined with the triplet pattern of the previous section. The theme eventually winds into the second theme again, this time in G major, using the end of the theme's tonic chord as an effective dominant chord transition into the main theme. The theme gradually diminishes and resolves in C major, resolving the piece's tension into tranquility. This is the longest impromptu in this set. The tonal ambiguity at the start of the piece highlights the romantic composer’s need for abstract imagery through music. Phrasing is not the I-V-I of times past, but a complete lack of tonal center until further into the tapestry Schubert is weaving for us.
No. 2 in E-flat major
The second impromptu, in E-flat major, starts off as a gentle melody but is transformed into a piece of great passion, encompassing Schubert's brilliance for music of personal anguish and sorrow with a beautiful hymn-like air in the middle section perfectly capturing feelings of fear, anger and uncertainty then again making use of minor-major contrasts when it is repeated, attempting to resolve the conflict.
No. 3 in G-flat major
Though written in G-flat major, the third was printed by the first publisher in G major. The original version is now generally preferred. Perhaps it is the daunting task of playing this beautiful sustained contrast of relatively slow, stationary themes with the constant rapid movement of broken triads in the middle registers. The piece exploits this contrast in order to establish the paradoxical impression of being simplistic and complex, static and dynamic, beautiful and brutish -- all at the same time. It is, in essence, a song-without-words.
No. 4 in A-flat major
The fourth Impromptu, in A-flat major, actually begins in A-flat minor, though this is written as A-flat major with accidentals. The opening theme consists of cascading arpeggios followed by murmuring chordal responses. These are repeated and developed, going through C-flat major and B minor before finally reaching A-flat major. There is a subordinate theme, accompanied by the arpeggio figure, varied with triplets. In the central section, in C# minor, the arpeggios are replaced by a chordal accompaniment. This section ventures into the major mode towards its conclusion, but reverts to the minor. This piece is marked allegretto but can withstand fantastic extremes of tempo.
Schubert's use of cascading arpeggios throughout this piece has led it to be nicknamed the "waterfall" Impromptu.
Four Impromptus, Op. post. 142 (D. 935)
As the first and last pieces in this set are in the same key (F Minor), and the set bears some resemblance to a 4-movement sonata, these Impromptus have been accused of being a sonata in disguise, notably by Robert Schumann and Alfred Einstein, who claim that Schubert called them Impromptus, and allowed them to be individually published to enhance their sales potential. However, this claim has been refuted by contemporary musicologists such as Charles Fisk, who established important differences between the set of Impromptus and Schubert's acknowledged multi-movement works.
No. 1 in F minor
This Impromptu is written in rondo form
. The returning A section appears always in the tonic, F minor; the first B section, B1
is in A-flat major, the relative major, whereas B2
is in the tonic. This structure can also be interpreted as a sonata form
without a development section, supporting the view of the four Impromptus as movements of a single sonata. The B episodes contain a passage invoking a unique pianistic effect: the left hand presents short melodic fragments in form of antecedent
, steadily alternating between the upper (antecedent, creating a crossing of the hands) and lower (consequent) registers of the instrument; the right hand accompanies with an even flow of semiquaver arpeggios
in the middle register; the sustain pedal
further enriches the sonority, and the dynamics
are mostly pianissimo
, as often in Schubert's music.
No. 2 in A-flat major
This Impromptu is written in the standard minuet
form. Its main section features a melody with chordal accompaniment. The opening bars of the melody are highly reminiscent of a similar theme, from the opening of Beethoven's piano sonata in A-flat, Opus 26
. Alfred Einstein has mentioned another similar theme by Beethoven - in the third movement of the Piano Trio Op. 70 #2
. The middle section of the Impromptu, marked Trio
as standard in minuets, is contrasted in character with the main section. It is written in D-flat major, and features continuous triplet motion. The second part of the Trio moves enharmonically
to C-sharp minor (the tonic minor), then climaxes on A major, fortissimo, and finally calms down and repeats the major-mode first phrase.
No. 3 in B-flat major
This Impromptu is a theme with variations
. The main theme resembles a theme from the incidental music
that Schubert composed for the play Rosamunde
, which also appears in the second movement of his 13th string quartet
No. 4 in F minor
This Impromptu contains interesting hemiola effects, brilliant passagework as well as cross modulations that take this piece to keys not traditionally associated with F minor. It is written roughly in Rondo form and contains a coda that further heightens the drama in this already intense piece.
Three Klavierstücke - D. 946
The three Klavierstücke D.946 are solo pieces composed by Schubert in May 1828, just six months before his early death. They were conceived as a third set of four Impromptus, but only three were written. They were first published in 1868, edited by Johannes Brahms
, although his name appears nowhere in the publication.
They do not rival the D.899 and D.935 sets in exposure or popularity. Indeed, they are largely neglected, not often heard either in the concert hall or on disc. Pianists who have recorded the pieces include Alfred Brendel on Philips and Maria Joao Pires and Maurizio Pollini on Deutsche Grammophon; the British pianist Peter Katin has also recorded them on a period (early-nineteenth-century) instrument.
No. 1 in E-flat minor
The main section (allegro assai) is in 2/4 time, though, as it is largely in triplets, the effect is like 6/8 for much of the time. It soon moves to E-flat major. As originally written, the piece had two trios, the first in B Major, andante in alla breve time, and the second in A-flat major, andantino in 2/4. Schubert crossed out the second, but it is not infrequently played also.
No. 2 in E-flat major
This is a highly lyrical and beautiful piece, lengthy, especially if all repeats are observed. (The first appearance of the main section and both trios are each in two sections, each repeated.) It is the most commonly heard of the set. The main section is an allegretto in 6/8 time. The first trio is in C minor and major (no change in meter or time signature) and the second in A-flat minor (l'istesso tempo in alla breve time).
No. 3 in C major
By far the shortest of the three, this is a lively piece (allegro) in 2/4, the main section of which exhibits much syncopation. The trio is in D-flat major and 3/2 time with no change in tempo indication. This is in two sections with repeats written out in a varied form. There is a substantial coda, again with syncopation.
Op. 90 No. 1 in C minor
Op. 142 No. 2, in A-flat major
Impromptu Op. posth. 142 (D. 935) No. 2.
Op. 142 No. 3, in B-flat major
Impromptu Op. posth. 142 (D. 935) No. 3 played by Randolph Hokanson
For the film Gattaca, Michael Nyman composed a version of the Impromptu in G-flat Major, op. 90, no. 3, for a genetically modified pianist with twelve fingers. One character says, "Twelve fingers or one, it's how you play." Another responds, "That piece can only be played with twelve."