The Sonata’s form is ABA and there are three musical ideas: one based on sharps (brightness), one based on flats (darkness), and one based on naturals (white notes), representing a kind of blank irrationality. The piece opens clangorously, its bold, assertive theme—sharps piled upon sharps—separated by small cadenzas. Yearning and hesitating to reach a cadence it finally stumbles into the B section where all accidentals are suddenly bleached away in a whiteout. Extremes of pitch and dynamics splatter sound across the keyboard until an arpeggio figure in the bass gathers rhythmic momentum and leads to the ‘flat’ musical idea, jarring in its romantic juxtaposition to what has gone before.
This whole B section is made up of a collision, a tossing and turning, between the two tonalities of flats and naturals, interrupting each other with impatience until the whiteout material spins up into the stratosphere, a whirlwind in the upper octaves of the piano. Under this blizzard we hear the theme from the beginning of the piece, first in purest, brilliant C major in the treble, then, after it subsides to pianissimo, in a snarl of dissonance in the extreme bass of the instrument. The music stops … and then, for the first time, we hear the full statement of the ‘flat’ material, Andante lamentoso. The music’s sorrow increases with wave after wave of romantic ardour, deliberately risking overkill and discomfort.
At its climax the music halts twice at a precipice then tumbles into the recapitulation, the opening theme now in white-note tonality and unrecognizably spotted across the keyboard. As this peters out we hear the same theme but now with warm, gentle, romantic harmonies. A final build-up to an exact repetition of the opening of the piece is blended with material from the B section and, in the last bar, in a final wild scream, we hear all three tonalities together for a blinding second-long flash, brighter than noon, before the final soft chord closes the curtain on these night visions.
from notes by Stephen Hough © 2014