A-sharp minor

A-sharp minor is a minor scale based on A, consisting of the pitches A, B, C, D, E, F, and G. Its key signature has seven sharps, while the direct enharmonic equivalent, B-flat minor, has five flats.
Its relative major is C-sharp major (or enharmonically D-flat major), and its parallel major is A-sharp major, usually replaced by B-flat major, since A-sharp major's three double-sharps make it impractical to use.
A-sharp minor is likely the least used minor key in music as it is not generally considered a practical key for composition. The enharmonic equivalent B-flat minor, which only contains five flats as opposed to A-sharp minor's seven sharps, is preferable to use.
The A-sharp natural minor scale is:
\override Score.TimeSignature #'stencil = ##f
\relative c" {
 \clef treble \key ais \minor \time 7/4
 ais4^\markup "Natural minor scale" bis cis dis eis fis gis ais gis fis eis dis cis bis ais2
</score>
Changes needed for the melodic and harmonic versions of the scale are written in with accidentals as necessary. The A-sharp harmonic minor and melodic minor scales are:
\override Score.TimeSignature #'stencil = ##f
\relative c" {
 \clef treble \key ais \minor \time 7/4
 ais4^\markup "Harmonic minor scale" bis cis dis eis fis gisis ais gisis fis eis dis cis bis ais2
</score>
\override Score.TimeSignature #'stencil = ##f
\relative c" {
 \clef treble \key ais \minor \time 7/4
 ais4^\markup "Melodic minor scale (ascending and descending)" bis cis dis eis fisis gisis ais gis! fis! eis dis cis bis ais2
</score>
In Rinck's 30 Preludes and Exercises in all major and minor keys, the 16th Prelude and Exercise is in A-sharp minor. In Bach's Prelude and Fugue in C-sharp major, a brief section near the beginning of the piece modulates to A-sharp minor. 