A♭ nine chordA♭9

Built from

• A♭root
• Cmajor 3rd
• E♭5th
• G♭flat 7th
• B♭9th

A dominant 7 with a 9th stacked on top: still restless, but richer.

Hear it in a progression

• ii–V–I

  The backbone of jazz. In D♭ major.

  Capo and transpose

  1. E♭m7ii7
  2. A♭9V7
  3. D♭maj7Imaj7
  4. D♭maj7Imaj7

• Blues opening

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

  Capo and transpose

  1. A♭9I9
  2. D♭7IV7
  3. A♭9I9
  4. A♭9I9

Where it goes next

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

• D♭maj7

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

• B♭m7

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

Sounds close

• Cm7

  Shares 3 of its notes. Both have C, E♭ and B♭.

• Cdim7

  Shares 3 of its notes. Both have C, E♭ and G♭.

• E♭m7

  Shares 3 of its notes. Both have E♭, G♭ and B♭.

• Fm7

  Shares 3 of its notes. Both have A♭, C and E♭.

Scales that fit

Notes you can play over this chord, simplest first.

• G♯ minor pentatonic
• G♯ blues
• A♭ mixolydian

Keys it lives in

• D♭ majoras V7
• B♭ minoras VII7