B-flat dominant seventh chord (Bb7)
The B♭ dominant seventh chord (B♭7) is a dominant seventh chord: a major triad with a minor seventh on top, B♭, D, F and A♭ (root, major third, perfect fifth and minor seventh).
It is the V7 in E♭ major and the V7 in E♭ minor, and it wants to resolve to E♭ major, a perfect fourth higher.
Below: voicings, notes on the fretboard, ukulele, piano, inversions and progressions.
How to play B♭ dominant seventh on guitar
There are 2 guitar voicings.
Frets from the 6th string to the 1st: x = not played, 0 = open string.
- Voicing 1: x-1-3-1-3-1, barre at fret 1, with B♭ in the bass (fingers x-1-3-1-4-1).
- Voicing 2: 6-8-6-7-6-6, movable E-shape barre chord at fret 6, with B♭ in the bass.
Notes of the B♭ dominant seventh chord on the fretboard
B♭ dominant seventh has 4 notes: B♭, D, F and A♭. This is where they fall on each string, from the nut to the 12th fret (fret number in parentheses):
- String 6 (E): F (1) · A♭ (4) · B♭ (6) · D (10)
- String 5 (A): B♭ (1) · D (5) · F (8) · A♭ (11)
- String 4 (D): D (0) · F (3) · A♭ (6) · B♭ (8) · D (12)
- String 3 (G): A♭ (1) · B♭ (3) · D (7) · F (10)
- String 2 (B): D (3) · F (6) · A♭ (9) · B♭ (11)
- String 1 (E): F (1) · A♭ (4) · B♭ (6) · D (10)
Formula and intervals of B♭ dominant seventh
Its formula is 1-3-5-♭7; in semitones from the root, 0-4-7-10.
- B♭: Root, the note that gives the chord its name
- D: Major third (M3), 4 semitones above B♭
- F: Perfect fifth (P5), 7 semitones above B♭
- A♭: Minor seventh (m7), 10 semitones above B♭
B♭ dominant seventh on ukulele
- Ukulele (G C E A): 1-2-1-1, barre at fret 1; it sounds A♭, D, F and B♭.
B♭ dominant seventh on piano
- Keys: B♭4, D5, F5 and A♭5.
Inversions of B♭ dominant seventh
Each inversion puts a different note in the bass.
- Root position: B♭, D, F and A♭, with B♭ in the bass.
- First inversion (B♭7/D): D, F, A♭ and B♭, with D in the bass.
- Second inversion (B♭7/F): F, A♭, B♭ and D, with F in the bass.
- Third inversion (B♭7/A♭): A♭, B♭, D and F, with A♭ in the bass.
Keys that use B♭ dominant seventh
B♭ dominant seventh appears in 3 major and minor keys.
| Key | Degree | Function |
|---|---|---|
| E♭ major (3 flats) | V7 | Dominant |
| C minor (3 flats) | VII7 | Subtonic |
| E♭ minor (harmonic minor, 6 flats) | V7 | Dominant |
Progressions with B♭ dominant seventh
- Jazz ii–V–I in E♭ major (ii7–V7–Imaj7): Fm7 – B♭7 – E♭maj7
- 12-bar blues in E♭ major (I7–IV7–V7): E♭7 – A♭7 – B♭7
- Minor cadence in E♭ minor (i–iv–V7): E♭m – A♭m – B♭7
B♭ dominant seventh or A♯ dominant seventh?
B♭ dominant seventh (B♭7) and A♯ dominant seventh (A♯7) are the same chord with two names: they sound the same and use the same frets.
The spelling depends on the key: it is written B♭ dominant seventh in flat keys and A♯ dominant seventh in sharp keys.
Frequently asked questions
What notes are in the B♭ dominant seventh chord?
B♭, D, F and A♭: root, major third, perfect fifth and minor seventh. Its formula is 1-3-5-♭7.
Which keys use B♭ dominant seventh?
Mainly as the V7 in E♭ major and the V7 in E♭ minor. In total it appears in 3 major and minor keys.
Is A♯ dominant seventh the same chord as B♭ dominant seventh?
Yes: A♯ dominant seventh and B♭ dominant seventh sound the same and are played the same way. It is written B♭ dominant seventh in flat keys and A♯ dominant seventh in sharp keys.
What chord does B♭ dominant seventh resolve to?
As a dominant seventh, B♭ dominant seventh (B♭, D, F and A♭) resolves naturally to E♭ major: its third rises a half step to the new tonic and its seventh falls to the third of the next chord.