B seven chordB7

Built from

• Broot
• D♯major 3rd
• F♯5th
• Aflat 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. F♯m7ii7
  2. B7V7
  3. Emaj7Imaj7
  4. Emaj7Imaj7

• Blues opening

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

  Capo and transpose

  1. B7I7
  2. E7IV7
  3. B7I7
  4. B7I7

Where it goes next

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

• Emaj7

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

• C♯m7

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

Sounds close

• Cdim7

  Shares 3 of its notes. Both have D♯, F♯ and A.

• A♭m7

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

• F7

  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