A#b13b9

Q: What notes are in the A#b13b9 chord?

The A#b13b9 chord (A# b13b9) contains: A#, D, E#, G#, B, F#. Its interval structure is shown above in the Theory section.

Q: How do I build A#b13b9 on the keyboard?

Take the root and add the remaining chord tones following the interval formula. The highlight shows chord content, while the inversion control changes which chord tone is in the bass.

Q: Which keys is A#b13b9 found in?

The chord acts as a diatonic degree in several keys — they are marked on the circle of fifths in the "Harmonic context" block.

Q: What can I substitute for A#b13b9?

A substitution depends on harmonic function and voice leading, not only on shared tones. Computed options appear in the "Substitutions" block and should be checked in context.

A# b13b9

Octaves

Musical context

ChordA# majorTriad

ChordA#b13b9A# b13b9

ArpeggioA# majorBroken triad

ScaleA# major7 notes

KeyA# majorMajor key

ProgressionPop axisSequence

How the chord relates to the scale, mode, key and progression.

Theory

General info

Full name: A# b13b9
Symbol: A#b13b9
Root: A#
Quality: b13b9

Chord notes

1A#root

3Dmajor 3rd

5E#perfect 5th

b7G#minor 7th

b2Bminor 2nd

b6F#minor 6th

Functions & resolutions

Stability / tension: Stable — can serve as major tonic
Most common resolutions: D#D# Major FF Major GmG Minor
Unstable degrees: 4D#
b7G#
resolves down to the resolution tonic
Main resolution: A#b13b9source
FF Major
Major chord A# is a stable tonic. As tonic it doesn't require resolution, but in a progression context typically moves to IV or V.
Other resolutions: A#b13b9source
Deceptive resolution
GmG Minor
As the V degree, a major chord can defy expectations by moving to vi instead of I (deceptive cadence).
A#b13b9source
Modal resolution
G#G# Major
In modal context, a major chord can freely move to bVII, bIII, or bVI — characteristic of Mixolydian mode.
A#b13b9source
Jazz reharmonization
A#maj7A# Major 7
In jazz, a major chord is enriched to maj7, 6/9, or add9 and can smoothly transition into a ii-V of another key (modulation).
A#b13b9source
Functional resolution
FF Major
As the IV degree (subdominant), a major chord can resolve to V or directly to I (plagal cadence).

Substitutions

Tritone substitution: E7E Dominant 7

Features

Character: Dominant, with b9 and b13
Characteristic interval: Minor 9th (b9), Minor 13th (b13)
Description: The minor 9th and minor 13th add two chromatically altered tones to a dominant seventh chord. Both commonly resolve by semitone, giving the chord sharp, directed tension.
Application: Altered dominants in minor
Jazz
Harmonic minor

Voicing & structure

Root position

v1A#(A#4)Bass

root

v2D(D5)M3from A#

v3E#(E#5)m3from D

v4G#(G#5)m3from E#

v5B(B5)m3from G#

v6F#(F#6)P5from B

Harmony

Compatible scales

All chord tones are contained in these scales — use them for improvisation.

ScaleF# Harmonic major ScaleG# Romanian minor ScaleG# Ukrainian Dorian ScaleA# Phrygian dominant ScaleD# Harmonic minor ScaleF# Bebop major ScaleD# Bebop melodic minor ScaleD Chromatic scale ScaleF Chromatic scale ScaleF# Chromatic scale

This chord on guitar 🎸

See how A#b13b9 looks on guitar.

Explore

Circle of fifths

Highlighted major keys contain this chord among their diatonic harmonies.

Relative key: GmG minor
Dominant: FF major
Subdominant: EbEb major
Key signature: 2 flats (Bb, Eb)

What to learn next

ScaleBb Chromatic scaleScale to improvise over this chord PracticeChord trainerLock the fingering into muscle memory ProgressionChord progressionsHow this chord works inside real progressions

Recommended for you

Bb Chromatic scaleA scale related to this chord

Practice

Keyboard Trainer

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Test yourself

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What notes are in the A#b13b9 chord?

How do I build A#b13b9 on the keyboard?

Which keys is A#b13b9 found in?

What can I substitute for A#b13b9?