B♭ minor major 7th chord on bass (B♭mMaj7)

Also called or written B♭mMaj7, B♭minmaj7, B♭mmaj7, B♭mM7, B♭ Minor Sharp 7 or B♭ Minor ♯7

B♭ minor major 7th contains B♭, D♭, F, and A. Its wide stretch from the 6th fret to the 8th fret demands careful finger placement.

6frB♭FAD♭EADG
Positions on the neck1 of 2
Practice B♭ minor major 7th chord

How it is built

B♭RootD♭Minor thirdFPerfect fifthAMajor seventh

Formula 1, ♭3, 5, 7

Inversions
  • Root positionB♭–D♭–F–AB♭mMaj76-8-7-6
  • First inversionD♭–F–A–B♭B♭mMaj7/D♭no shape on this instrument
  • Second inversionF–A–B♭–D♭B♭mMaj7/Fno shape on this instrument
  • Third inversionA–B♭–D♭–FB♭mMaj7/A5-4-3-3

How do you play a B♭ minor major 7th chord on bass?

B♭ minor major 7th is played at the 6th fret as 6 8 7 6: index finger on the E string at fret 6, pinky finger on the A string at fret 8, ring finger on the D string at fret 7 and middle finger on the G string at fret 6.

Full note and interval breakdown
StringFretFingerNote
4 (E)61B♭ (1)
3 (A)84F (5)
2 (D)73A (7)
1 (G)62D♭ (♭3)

AdvancedThe pinky must stretch to the 8th fret on the A string while the index stays at the 6th fret on the E string.

B♭minmaj7/A inversion

B♭ minor major 7th is played at the 3rd fret as 5 4 3 3: pinky finger on the E string at fret 5, ring 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
StringFretFingerNote
4 (E)54A (7)
3 (A)43D♭ (♭3)
2 (D)31F (5)
1 (G)32B♭ (1)

Why it sounds like that

B♭ minor major 7th is built from the formula 1, ♭3, 5, 7. The minor 3rd between B♭ and D♭ gives the chord its minor quality, while the major 7th between B♭ and A adds a leading tone. Contrast this with B♭ minor, which omits the major 7th.

What goes wrong with B♭ minor major 7th?

  • Letting the pinky collapse and buzz the A string at the 8th fret.

When to use it

Use B♭ minor major 7th in jazz ballads or neo-soul lines where the major 7th adds tension. Pair it with B♭ minor or B♭ 5th for contrast.

Changing to and from B♭ minor major 7th

  • Sliding the shape down two frets to the 4th fret gives A♭ minor major 7th.
  • Sliding the shape up two frets to the 8th fret gives C minor major 7th.

Which voicing to use

The 6th fret position keeps B♭ in the bass for a grounded sound. The B♭minmaj7/A inversion places A in the bass, creating a smoother voice leading into chords like B♭ minor.

Other B♭ chords

Common questions

How is B♭ minor major 7th written?

B♭ minor major 7th is written as B♭mmaj7, mmaj7, mM7, or B♭minmaj7. The root can be typed as Bb. It is also spelled A♯ in enharmonic notation for the same sounding root.

What is the difference between B♭ minor major 7th and B♭ minor 7th?

B♭ minor major 7th has a major 7th (A), while B♭ minor 7th has a minor 7th (A♭). The major 7th creates a leading tone that pulls strongly to the root.

Why does B♭ minor major 7th sound dissonant?

The minor 3rd (D♭) and major 7th (A) form an augmented 5th interval, which is unstable. This tension is characteristic of the minor major 7th chord.

Can I play B♭ minor major 7th in a lower register?

Yes, the B♭minmaj7/A inversion at the 3rd fret places the major 7th in the bass. This voicing is useful for connecting to chords with A in the bass.