Parallel key G♯ minor | Enharmonic A♭ major | |
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Relative key E♯ minor
enharmonic: F minor Dominant key D♯ major
enharmonic: E♭ major Subdominant C♯ major
enharmonic: D♭ major | ||
G-sharp major is a theoretical key based on the musical note G-sharp, consisting of the pitches G♯, A♯, B♯, C♯, D♯, E♯ and F. Its key signature has six sharps and one double sharp.
Although G♯ major is usually notated as the enharmonic key of A♭ major, because A♭ major has only four flats as opposed to G♯ major's eight sharps (including the F), it does appear as a secondary key area in several works in sharp keys - most notably in the Prelude and Fugue in C-sharp major from Johann Sebastian Bach's The Well-Tempered Clavier, Book 1. The G-sharp minor prelude (and, in some editions, the fugue) from the same set ends with a Picardy third, on a G-sharp major chord.
G-sharp major is tonicised briefly in several of Frédéric Chopin's nocturnes in C-sharp minor. A section in the second movement of Chopin's Piano Concerto No. 1 is in G-sharp major, although the key signature has 4 sharps. The end of the exposition of the second movement Charles-Valentin Alkan's Grande sonate 'Les quatre âges', subtitled Quasi-Faust, is in G-sharp major, albeit written with a six-sharp key signature (the movement opens in D-sharp minor and ends in F-sharp major).
The final pages of A World Requiem by John Foulds are written in G-sharp major with its correct key signature shown in the vocal score including the F.