A♭ Dominant Ninth Chord

Chord Tones: A♭ Dominant Ninth Chord

Symbol: 9 — Formula: 1-3-5-♭7-9

DegreeNoteFrequency (A=440, Equal)
1 A♭4 415.305 Hz
3 C4 261.626 Hz
5 E♭4 311.127 Hz
♭7 G♭4 369.994 Hz
9 B♭4 466.164 Hz

Chord Notation

Notation TypeSymbol / Value
Lead Sheet SymbolA♭9
All Common Symbols9
Interval Formula1-3-5-♭7-9
Harmonic Categorytense

Roman numeral (e.g. I, IV, V) and Nashville Number notation are key-dependent. See Keys pages for chord function within specific keys.

Inversions

InversionNotes (low to high)Bass NoteSlash Notation
Root Position A♭4 C4 E♭4 G♭4 B♭4 A♭ A♭ Dominant Ninth Chord
First Inversion C4 E♭4 G♭4 B♭4 A♭4 C A♭ Dominant Ninth Chord/C
Second Inversion E♭4 G♭4 B♭4 A♭4 C4 E♭ A♭ Dominant Ninth Chord/E♭
Third Inversion G♭4 B♭4 A♭4 C4 E♭4 G♭ A♭ Dominant Ninth Chord/G♭
Fourth Inversion B♭4 A♭4 C4 E♭4 G♭4 B♭ A♭ Dominant Ninth Chord/B♭

Harmonic Function

The A♭ dominant ninth chord commonly functions as the submediant (♭VI) in C minor or subdominant in E♭ major. Its harmonic role varies by key — in major keys it provides stable harmonic grounding.

The dominant ninth chord extends the dominant seventh with a ninth, adding color and richness to one of music's most harmonically active chords. Essential in jazz, blues, and funk. The A♭ Dominant Ninth Chord specifically contains 5 notes: A♭, C, E♭, G♭, B♭ (formula: 1-3-5-♭7-9). On piano, Ab-rooted chords use a combination of black and white keys that creates a relaxed hand shape, favored by Romantic-era composers for lyrical passages. Pop ballads, film scores, and neo-soul tracks often use Ab chords for their warm, enveloping quality — the key sits comfortably for many vocal ranges.

Common Progressions

The A♭ Dominant Ninth Chord frequently appears in these progression patterns (shown in Roman numeral notation relative to key):

Songs Featuring the Dominant Ninth Chord

Well-known songs where the A♭ Dominant Ninth Chord — or this chord type — plays a prominent role:

Tuning Frequencies Across Temperaments

Frequencies shown at A=440 Hz. View full temperament data for any note.

NoteEqual Temp.PythagoreanJust Intonation
A♭4 415.305 Hz 417.657 Hz 418.601 Hz
C4 261.626 Hz 260.740 Hz 261.626 Hz
E♭4 311.127 Hz 309.026 Hz 313.951 Hz
G♭4 369.994 Hz 371.251 Hz 367.911 Hz
B♭4 466.164 Hz 463.538 Hz 470.926 Hz

Scales Containing the A♭ Dominant Ninth Chord

These scales include the A♭ Dominant Ninth Chord as a diatonic or characteristic chord: