A♭ Augmented Seventh Chord
Chord Tones: A♭ Augmented Seventh Chord
Symbol: aug7, +7, 7♯5 — Formula: 1-3-♯5-♭7
| Degree | Note | Frequency (A=440, Equal) |
|---|---|---|
| 1 | A♭4 | 415.305 Hz |
| 3 | C4 | 261.626 Hz |
| ♯5 | E4 | 329.628 Hz |
| ♭7 | G♭4 | 369.994 Hz |
Chord Notation
| Notation Type | Symbol / Value |
|---|---|
| Lead Sheet Symbol | A♭aug7 |
| All Common Symbols | aug7, +7, 7♯5 |
| Interval Formula | 1-3-♯5-♭7 |
| Harmonic Category | unstable |
Roman numeral (e.g. I, IV, V) and Nashville Number notation are key-dependent. See Keys pages for chord function within specific keys.
Inversions
| Inversion | Notes (low to high) | Bass Note | Slash Notation |
|---|---|---|---|
| Root Position | A♭4 – C4 – E4 – G♭4 | A♭ | A♭ Augmented Seventh Chord |
| First Inversion | C4 – E4 – G♭4 – A♭4 | C | A♭ Augmented Seventh Chord/C |
| Second Inversion | E4 – G♭4 – A♭4 – C4 | E | A♭ Augmented Seventh Chord/E |
| Third Inversion | G♭4 – A♭4 – C4 – E4 | G♭ | A♭ Augmented Seventh Chord/G♭ |
Harmonic Function
The A♭ augmented seventh 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 extended harmonic tension.
The augmented seventh chord adds a minor seventh to the augmented triad, combining the restlessness of an augmented fifth with the tension of a dominant seventh. Used for maximum harmonic tension. The A♭ Augmented Seventh Chord specifically contains 4 notes: A♭, C, E, G♭ (formula: 1-3-♯5-♭7). 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♭ Augmented Seventh Chord frequently appears in these progression patterns (shown in Roman numeral notation relative to key):
Songs Featuring the Augmented Seventh Chord
Well-known songs where the A♭ Augmented Seventh Chord — or this chord type — plays a prominent role:
- Whole Lotta Love – Led Zeppelin
- Come Together – Beatles (chord variant)
- Spanish Key – Miles Davis
Tuning Frequencies Across Temperaments
Frequencies shown at A=440 Hz. View full temperament data for any note.
| Note | Equal Temp. | Pythagorean | Just Intonation |
|---|---|---|---|
| A♭4 | 415.305 Hz | 417.657 Hz | 418.601 Hz |
| C4 | 261.626 Hz | 260.740 Hz | 261.626 Hz |
| E4 | 329.628 Hz | 330.001 Hz | 327.032 Hz |
| G♭4 | 369.994 Hz | 371.251 Hz | 367.911 Hz |
Scales Containing the A♭ Augmented Seventh Chord
These scales include the A♭ Augmented Seventh Chord as a diatonic or characteristic chord: