A Dominant Seventh Chord
Chord Tones: A Dominant Seventh Chord
Symbol: 7 — Formula: 1-3-5-♭7
| Degree | Note | Frequency (A=440, Equal) |
|---|---|---|
| 1 | A | 440.000 Hz |
| 3 | C# | 277.183 Hz |
| 5 | E | 329.628 Hz |
| ♭7 | G | 391.995 Hz |
Chord Notation
| Notation Type | Symbol / Value |
|---|---|
| Lead Sheet Symbol | A7 |
| All Common Symbols | 7 |
| Interval Formula | 1-3-5-♭7 |
| Harmonic Category | tense |
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# – E – G | A | A Dominant Seventh Chord |
| First Inversion | C# – E – G – A | C# | A Dominant Seventh Chord/C# |
| Second Inversion | E – G – A – C# | E | A Dominant Seventh Chord/E |
| Third Inversion | G – A – C# – E | G | A Dominant Seventh Chord/G |
Harmonic Function
The A dominant 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 dominant seventh chord is the most harmonically active chord in Western music. Its tritone between the third and flat seventh creates strong tension that resolves naturally to the tonic.
Common Progressions
The A Dominant Seventh Chord frequently appears in these progression patterns (shown in Roman numeral notation relative to key):
V7-Iii-V7-I
Songs Featuring the Dominant Seventh Chord
Well-known songs where the A Dominant Seventh Chord — or this chord type — plays a prominent role:
- Johnny B. Goode – Chuck Berry
- Sweet Home Chicago – Robert Johnson
- Fly Me to the Moon – Frank Sinatra
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 |
| E | 329.628 Hz | 330.001 Hz | 327.032 Hz |
| G | 391.995 Hz | 391.111 Hz | 392.438 Hz |
Scales Containing the A Dominant Seventh Chord
These scales include the A Dominant Seventh Chord as a diatonic or characteristic chord: