D Augmented Seventh Chord
Chord Tones: D Augmented Seventh Chord
Symbol: aug7, +7, 7♯5 — Formula: 1-3-♯5-♭7
| Degree | Note | Frequency (A=440, Equal) |
|---|---|---|
| 1 | D4 | 293.665 Hz |
| 3 | F♯4 | 369.994 Hz |
| ♯5 | A♯4 | 466.164 Hz |
| ♭7 | C4 | 261.626 Hz |
Chord Notation
| Notation Type | Symbol / Value |
|---|---|
| Lead Sheet Symbol | Daug7 |
| 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 | D4 – F♯4 – A♯4 – C4 | D | D Augmented Seventh Chord |
| First Inversion | F♯4 – A♯4 – C4 – D4 | F♯ | D Augmented Seventh Chord/F♯ |
| Second Inversion | A♯4 – C4 – D4 – F♯4 | A♯ | D Augmented Seventh Chord/A♯ |
| Third Inversion | C4 – D4 – F♯4 – A♯4 | C | D Augmented Seventh Chord/C |
Harmonic Function
The D augmented seventh chord commonly functions as the supertonic (ii) in C major or dominant (V) in G 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 D Augmented Seventh Chord specifically contains 4 notes: D, F♯, A♯, C (formula: 1-3-♯5-♭7). On guitar, D-rooted chords use the open D string as their bass note, and the compact open-D shape is one of the most recognizable chord voicings. Rock anthems and folk songs frequently center on D chords, which provide a bright, cutting tone that projects well in ensemble settings.
Common Progressions
The D 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 D 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 |
|---|---|---|---|
| D4 | 293.665 Hz | 293.332 Hz | 294.329 Hz |
| F♯4 | 369.994 Hz | 371.251 Hz | 367.911 Hz |
| A♯4 | 466.164 Hz | 463.538 Hz | 470.926 Hz |
| C4 | 261.626 Hz | 260.740 Hz | 261.626 Hz |
Scales Containing the D Augmented Seventh Chord
These scales include the D Augmented Seventh Chord as a diatonic or characteristic chord: