A+7(b9) Augmented
The A+7(b9) chord is built from the notes A – C# – E# – G – Bb.
Piano sound loads on first tap.
Also known as
A+7b9A7#5b9A7(#5,b9)A7(#5b9)A7+b9A7b9#5Aaug7(no5)b9Aaug7b9
Chord tones, one by one
ARoot
Root
The fundamental note the chord is built on — A.
C#Third
Major third
Four semitones — makes the chord major (brighter, happier).
E#Fifth
Augmented fifth (♯5)
Eight semitones — a sharp fifth. Restless and dreamy, typical of augmented chords.
GSeventh
Minor seventh (♭7)
Ten semitones — the dominant/minor seventh. Adds bluesy tension (7, m7).
BbExtension
Flat ninth (♭9)
A ♭9 — sharp, dissonant tension typical of altered dominant chords.
🎼 Related scales
Altered (super-Locrian)melodic minor a semitone above
🎹 Modal analysis
This chord implies the Altered (super-Locrian) scale; its characteristic note is the ♭13, a dominant's maximum tension. It is a mode of the melodic minor a semitone above.
🎸 Genres
Modern jazz · Post-bop · Fusion