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 | 440.000 Hz |
| 3 | C# | 277.183 Hz |
| ♯5 | F | 349.228 Hz |
| ♭7 | G | 391.995 Hz |
Chord Notation
| Notation Type | Symbol / Value |
|---|---|
| Lead Sheet Symbol | Aaug7 |
| 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 – C# – F – G | A | A Augmented Seventh Chord |
| First Inversion | C# – F – G – A | C# | A Augmented Seventh Chord/C# |
| Second Inversion | F – G – A – C# | F | A Augmented Seventh Chord/F |
| Third Inversion | G – A – C# – F | G | A Augmented Seventh Chord/G |
Harmonic Function
The A augmented seventh chord commonly functions as the submediant (vi) in C major or dominant (V) in D 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.
Common Progressions
The A Augmented Seventh Chord frequently appears in these progression patterns (shown in Roman numeral notation relative to key):
V+7-II+7-IV
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 | 440.000 Hz | 440.000 Hz | 436.043 Hz |
| C# | 277.183 Hz | 278.437 Hz | 279.067 Hz |
| F | 349.228 Hz | 347.654 Hz | 348.834 Hz |
| G | 391.995 Hz | 391.111 Hz | 392.438 Hz |
Scales Containing the A Augmented Seventh Chord
These scales include the A Augmented Seventh Chord as a diatonic or characteristic chord: