F-flat major

F♭ major

Relative key	D♭ minor enharmonic: C♯ minor
Parallel key	F♭ minor enharmonic: E minor
Dominant key	C♭ major enharmonic: B major
Subdominant	B major enharmonic: A major
Enharmonic	E major
Component pitches
F♭, G♭, A♭, B, C♭, D♭, E♭, F♭

F-flat major is a theoretical key based on F♭, consisting of the pitches F♭, G♭, A♭, B, C♭, D♭, and E♭. Its key signature has six flats and one double flat.^[1]

Its relative minor is D♭ minor, usually replaced by C♯ minor (see reason below) and its parallel minor is F♭ minor, usually replaced by E minor, since F♭ minor's four double-flats make it generally impractical to use.

Part of Richard Strauss' Metamorphosen uses F♭ major, which one commentator has called "a bitter enharmonic parody" of the earlier manifestations of E major in the piece.^[2]

For clarity and simplicity, F♭ major is usually notated as its enharmonic equivalent of E major, because E major has 4 sharps only as opposed to F-flat major's 8 flats (including the B-double-flat).

A well-known example can be found in Beethoven's Piano Sonata No. 31, op. 110. In the first movement's exposition, the transitional passage between the first and second subjects consists of arpeggiated figuration beginning in A♭ major and modulating to the dominant key of E♭ major. In the recapitulation, the key for this passage is changed to bring the second subject back in A♭ major: the transitional passage appears in a key that would theoretically be F♭ major, but which is notated in E major, presumably because Beethoven judged this easier to read - this key being a major third below the key of the earlier appearance of this passage.

Another example of F♭ major being notated as E major can be found in the Adagio of Haydn's Trio No. 27 in A-flat major. The Finale of Bruckner's Symphony No. 4 employs enharmonic E for F♭, but its Coda employs F♭ directly, with a phrygian cadence through F♭ onto the tonic.^[3][4][5]

An example of F♭ major being used directly is in Victor Ewald's Quintet no. 4 in A flat major (Op. 8), where the entirety of the third movement is notated in this key.^[6]

References

1. Nicolas Slonimsky (1960). The Road to Music. New York: Dodd, Mead, & Co. p. 16.
2. Bryan Randolph Gilliam (1998). Richard Strauss: New Perspectives on the Composer and His Work. Duke University Press. p. 237. ISBN 0-8223-2114-9.
3. Donald Betts (2005). "Beethoven’s Piano Sonata Opus 110". The Inner Voice.
4. James Arnold Hepokoski and Warren Darcy (2006). Elements of Sonata Theory: Norms, Types, and Deformations in the Late-Eighteenth-Century Sonata. Oxford University Press. p. 326. ISBN 0-19-514640-9.
5. Julian Horton (2004). Bruckner's Symphonies: Analysis, Reception and Cultural Politics. Cambridge University Press. p. 127. ISBN 0-521-82354-4.
6. "Ewald: Quintet No 4 in Ab, op 8". Ensemble Publications. Ensemble Publications. Retrieved 8 February 2016.

Scales and keys