Explore chords · Bass
B♭ minor 7th chord on bass (B♭m7)
Also called or written B♭m7 or B♭min7
B♭ minor 7th is built from B♭, D♭, F, and A♭. This advanced bass shape stretches the pinky to the 8th fret while the other fingers hold the 6th.
How it is built
Formula 1, ♭3, 5, ♭7
- Root positionB♭–D♭–F–A♭B♭m76-8-6-6
- First inversionD♭–F–A♭–B♭B♭m7/D♭no shape on this instrument
- Second inversionF–A♭–B♭–D♭B♭m7/F13-13-11-13
- Third inversionA♭–B♭–D♭–FB♭m7/A♭4-4-3-3
How do you play a B♭ minor 7th chord on bass?
B♭ minor 7th is played at the 6th fret as 6 8 6 6: index finger on the E string at fret 6, pinky finger on the A string at fret 8, middle finger on the D string at fret 6 and ring finger on the G string at fret 6.
Full note and interval breakdown
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | 6 | 1 | B♭ (1) |
| 3 (A) | 8 | 4 | F (5) |
| 2 (D) | 6 | 2 | A♭ (♭7) |
| 1 (G) | 6 | 3 | D♭ (♭3) |
AdvancedThe pinky must reach the 8th fret on the A string while the other fingers stay at the 6th fret, requiring a wide stretch.
B♭m7/F inversion
B♭ minor 7th is played at the 11th fret as 13 13 11 13: middle finger on the E string at fret 13, ring finger on the A string at fret 13, index finger on the D string at fret 11 and pinky finger on the G string at fret 13.
Full note and interval breakdown
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | 13 | 2 | F (5) |
| 3 (A) | 13 | 3 | B♭ (1) |
| 2 (D) | 11 | 1 | D♭ (♭3) |
| 1 (G) | 13 | 4 | A♭ (♭7) |
B♭m7/A♭ inversion
B♭ minor 7th is played at the 3rd fret as 4 4 3 3: ring finger on the E string at fret 4, pinky finger on the A string at fret 4, index finger on the D string at fret 3 and middle finger on the G string at fret 3.
Full note and interval breakdown
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | 4 | 3 | A♭ (♭7) |
| 3 (A) | 4 | 4 | D♭ (♭3) |
| 2 (D) | 3 | 1 | F (5) |
| 1 (G) | 3 | 2 | B♭ (1) |
Why it sounds like that
B♭ minor 7th uses the formula 1, ♭3, 5, ♭7. The ♭3 gives it a minor quality, and the ♭7 adds a darker edge compared to B♭ minor. The interval between B♭ and A♭ is a minor 7th, and between B♭ and D♭ is a minor 3rd.
What goes wrong with B♭ minor 7th?
- Letting the pinky flatten and buzz the 3rd string at the 8th fret.
- Allowing the index finger to touch the 3rd string and deaden the note.
- Strumming too hard and causing the 2nd and 1st strings to ring unevenly.
When to use it
B♭ minor 7th works in the I–V–vi–IV progression in C♯ major, where it is the vi chord. It suits minor-key ballads and smooth R&B bass lines, especially when paired with B♭ minor.
Changing to and from B♭ minor 7th
- Sliding the shape down two frets to the 4th fret gives A♭ minor 7th.
- Sliding the shape up one fret to the 7th fret gives B minor 7th.
Which voicing to use
The 6th fret position puts B♭ in the bass for a root-position sound. The B♭m7/F inversion at the 13th fret places F in the bass, softening the chord, while the B♭m7/A♭ inversion at the 4th fret uses A♭ in the bass for a darker, more suspended feel.
Other B♭ chords
Common questions
How is B♭ minor 7th written?
B♭ minor 7th is written as B♭min7 or B♭m7. On a keyboard, the root is typed as Bb. It is also spelled A♯ in enharmonic notation for the same sounding root.
What is the difference between B♭ minor 7th and B♭ minor?
B♭ minor 7th adds the ♭7, A♭, to the B♭ minor triad. This extra note creates a minor 7th interval from the root, giving the chord a more complex, jazzy color.
Can B♭ minor 7th be played in a lower register?
Yes, the B♭m7/A♭ inversion at the 4th fret places the chord lower on the neck. This voicing puts A♭ in the bass and works well for creating a darker tone.
What is the hardest part of playing B♭ minor 7th?
The stretch between the index finger on the 6th fret and the pinky on the 8th fret is the main challenge. Keeping the pinky arched and the other fingers close to the frets helps maintain clarity.