B♭ seven chordB♭7

Built from

• B♭root
• Dmajor 3rd
• F5th
• A♭flat 7th

The flat 7th rubs against the major 3rd, and that tension wants to resolve.

Hear it in a progression

• ii–V–I

  The backbone of jazz. In E♭ major.

  Capo and transpose

  1. Fm7ii7
  2. B♭7V7
  3. E♭maj7Imaj7
  4. E♭maj7Imaj7

• Blues opening

  The first four bars of a twelve-bar blues. In B♭ major.

  Capo and transpose

  1. B♭7I7
  2. E♭7IV7
  3. B♭7I7
  4. B♭7I7

Where it goes next

Thinking in E♭ major, where it is the V7 chord.

• E♭maj7

  Imaj7. The strongest pull in music: tension resolving home.

• Cm7

  vi7. The fake-out: you expect home, you get the relative minor.

Sounds close

• Ddim7

  It is this chord without its root: a darker stand-in. Both have D, F and A♭.

• Gm7

  Shares 3 of its notes. Both have B♭, D and F.

• E7

  Tritone substitute: swaps in for it in jazz. Both have D and A♭.

• D♭

  Shares 2 of its notes. Both have F and A♭.

Scales that fit

Notes you can play over this chord, simplest first.

• B♭ major pentatonic
• B♭ minor pentatonic
• B♭ blues
• B♭ mixolydian

Keys it lives in

• E♭ majoras V7
• C minoras VII7