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Chord & Fret

A7(b9) — dominant flat ninth

Notes in A7(b9): A – C# – E – G – BbFormula: 1 – 3 – 5 – b7 – b9

In the formula, the numbers count steps of the major scale starting from the note that names the chord; "b" lowers a half step, "#" raises one — and a slash names the bass note.

The 7(b9) is a dramatic dominant. The minor ninth intensifies the resolution, especially when the target chord is minor.

The same chord on all four instruments

A7(b9), 5 0 5 3 2 0A7(b9)3421AAGBbDbE
Guitar
A7(b9), 5 0 5 3 2 0A7(b9)3421AAGBbDbE
Electric guitar
A7(b9), 7 6 8 8A7(b9)62134ADbGBb
Cavaquinho
A7(b9), 3 1 3 0A7(b9)213BbDbGA
Ukulele

Where to use it: A dominant that resolves to a minor chord.

The shapes of A7(b9) don't end on this page — the whole neck holds dozens. In Chord & Fret, you hear every shape strummed string by string, in each instrument's own voice; compare positions with their difficulty marked; and change the tuning — the shape rewrites itself. Start free. Unlock everything with Pro. Plays offline.

See the whole neck in Chord & Fret →

Part of the Altered dominants family.

Other chords in this family

A7(#9)A7(#11)A7(b13)A7alt

See all chord types and qualities →