About the A sharp major thirteen chord
The A sharp major thirteen chord is a A sharp major thirteenth built from A sharp, C double sharp, E sharp, G double sharp, B sharp, F double sharp. It sits outside the plain diatonic set, so it is borrowed to add color and tension.
It is also written B flat major thirteen , which spells the same notes enharmonically.
In shorthand it is commonly written A#maj13.
Positions
(root position)
Notes and intervals
| 1 | A sharp | Root |
| 2 | C double sharp | Major 3rd |
| 3 | E sharp | Perfect 5th |
| 4 | G double sharp | Major 7th |
| 5 | B sharp | Major 9th |
| 6 | F double sharp | Major 13th |
Shapes
Chromatic
Circle of Fifths
Other A sharp chords
Simpler triads
Suspended
Sixths and sevenths
Extensions
Altered
Functional relationships
These chords are where this one most naturally comes from and resolves to inside a key.
Relative minor
The relative minor uses the same notes and key signature, so it works as a calmer, darker home base.
Parallel minor
The parallel minor keeps the same root note but lowers the third, giving the same key a darker, sadder sound.
Dominant
The dominant is a fifth above the root, and it builds tension that pulls strongly back to this chord.
Subdominant
The subdominant is a fourth above the root (a fifth below), and it usually leads on to the dominant or back home.
Tritone substitution
The tritone substitution stands in for this chord's dominant with a dominant seventh a half step above the root, which slides down by a half step to resolve here.
