Un Sospiro - Three Concert Études (S. 144 No. 3), F. Liszt

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Three Concert Études (Trois études de concert), S.144, is a set of three piano études by Franz Liszt, composed between 1845-49 and published in Paris as Trois caprices poétiques with the three individual titles as they are known today.
The third of the Three Concert Études is in D-flat major, and is usually known as Un sospiro (Italian for "A sigh"). However, it is likely that the title did not originate with Liszt. Although there is no evidence that he actively attempted to remove the subtitle, none of the editions or subsequent printings of the Three Concert Études published by Kistner during Liszt's lifetime used them; he simply ignored such subtitles in later years, always referring to the piece by key.
The étude is a study in crossing hands, playing a simple melody with alternating hands, and arpeggios. It is also a study in the way hands should affect the melody with its many accentuations, or phrasing with alternating hands. The melody is quite dramatic, almost impressionistic, radically changing in dynamics at times, and has inspired many listeners. The étude has been considered by many pianists as one of the most beautiful piano pieces ever composed. Liszt kept the étude in his repertoire until his final years.
Un sospiro consists of a flowing background superimposed by a simple melody written in the third staff. This third staff-an additional treble staff-is written with the direction to the performer that notes with the stem up are for the right hand and notes with the stem down are for the left hand. The background alternates between the left and right hands in such a way that for most of the piece, while the left hand is playing the harmony, the right hand is playing the melody, and vice versa, with the left hand crossing over the right as it continues the melody for a short while before regressing again. There are also small cadenza sections requiring delicate fingerwork throughout the middle section of the piece.
Towards the end, after the main climax of the piece, both hands are needed to cross in an even more complex pattern. Since there are so many notes to be played rapidly and they are too far away from other clusters of notes that must be played as well, the hands are required to cross multiple times to reach dramatic notes near the end of the piece on the last page.
This étude, along with the other Three concert études, was written in dedication to Liszt's uncle, Eduard Liszt (1817-1879), the youngest son of Liszt's grandfather and the stepbrother of his own father. Eduard handled Liszt's business affairs for more than thirty years until his death in 1879.