C-sharp major
C-sharp major (or the key of C-sharp) is a major scale based on C♯, consisting of the pitches C♯, D♯, E♯, F♯, G♯, A♯, and B♯. It is enharmonically equivalent to D-flat major. Its key signature has seven sharps. Its relative minor is A-sharp minor (or enharmonically B-flat minor) and its parallel minor is C-sharp minor.
Relative key
G-sharp major (theoretical)
→enharmonic A-flat major
F-sharp major
→enharmonic G flat major
The C-sharp major scale is:
A harp tuned to C-sharp major has all its pedals in the bottom position. Because all the strings are then pinched and shortened, this is the least resonant key for the instrument.
Compositions[edit]
Most composers prefer to use the enharmonic equivalent D-flat major since it contains five flats as opposed to C-sharp major's seven sharps. However, Johann Sebastian Bach chose C-sharp major for Prelude and Fugue No. 3 in both books of The Well-Tempered Clavier. In Hungarian Rhapsody No. 6, Franz Liszt takes the unusual step of changing the key from D-flat major to C-sharp major near the start of the piece, and then back again to B-flat minor. Maurice Ravel selected C-sharp major as the tonic key of "Ondine" from his piano suite Gaspard de la nuit. Erich Wolfgang Korngold composed his Piano Concerto for the Left Hand, Op. 17, in C-sharp.
The Allegro de concierto by Spanish composer Enrique Granados is written in C-sharp major. Canadian composer and pianist Frank Mills originally wrote and performed his instrumental hit "Music Box Dancer" in C-sharp major; however, most modern piano editions have the piece written in C major.
Louis Vierne used C-sharp major for the "Dona nobis pacem" of the Agnus Dei of his Messe solennelle in C-sharp minor.