B♭ Augmented Triad
Chord Tones: B♭ Augmented Triad
Symbol: aug, + — Formula: 1-3-♯5
| Degree | Note | Frequency (A=440, Equal) |
|---|---|---|
| 1 | B♭4 | 466.164 Hz |
| 3 | D4 | 293.665 Hz |
| ♯5 | G♭4 | 369.994 Hz |
Chord Notation
| Notation Type | Symbol / Value |
|---|---|
| Lead Sheet Symbol | B♭aug |
| All Common Symbols | aug, + |
| Interval Formula | 1-3-♯5 |
| 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 | B♭4 – D4 – G♭4 | B♭ | B♭ Augmented Triad |
| First Inversion | D4 – G♭4 – B♭4 | D | B♭ Augmented Triad/D |
| Second Inversion | G♭4 – B♭4 – D4 | G♭ | B♭ Augmented Triad/G♭ |
Harmonic Function
The B♭ augmented chord commonly functions as the subtonic (♭VII) in C major or subdominant in F major. Its harmonic role varies by key — in major keys it provides stable harmonic grounding.
The augmented triad consists of two stacked major thirds, creating a symmetrical, ambiguous chord. Its raised fifth gives it a tense, unresolved quality that pulls toward resolution.
Common Progressions
The B♭ Augmented Triad frequently appears in these progression patterns (shown in Roman numeral notation relative to key):
Songs Featuring the Augmented Triad
Well-known songs where the B♭ Augmented Triad — or this chord type — plays a prominent role:
- Oh! You Pretty Things – David Bowie
- All Blues – Miles Davis
- Michelle – The Beatles
Tuning Frequencies Across Temperaments
Frequencies shown at A=440 Hz. View full temperament data for any note.
| Note | Equal Temp. | Pythagorean | Just Intonation |
|---|---|---|---|
| B♭4 | 466.164 Hz | 463.538 Hz | 470.926 Hz |
| D4 | 293.665 Hz | 293.332 Hz | 294.329 Hz |
| G♭4 | 369.994 Hz | 371.251 Hz | 367.911 Hz |
Scales Containing the B♭ Augmented Triad
These scales include the B♭ Augmented Triad as a diatonic or characteristic chord: