Who Barry Harris was
Barry Harris (1929–2021), a Detroit pianist tied to the bebop of Bud Powell and Charlie Parker, was for decades one of the great jazz educators with his workshops in New York and around the world. His harmonic method rests on a simple idea: the sixth chord and the diminished chord are one family, and by alternating them you get continuous harmonic movement over a single chord.
The diminished sixth scale (major)
C major + a chromatic note between G and A:
C D E F G G# A B (eight notes).
- The notes of C6: C E G A
- The notes of B°7: B D F G# (= Ab)
The two seventh chords interlock: every note of the scale belongs to one of the two chords. Playing the scale in block chords, note by note, alternates C6 and B°7 in all inversions:
| Melody | Chord | Voicing (from the bottom) |
|---|---|---|
| C | C6 | E G A C |
| D | B°7 | F G# B D |
| E | C6 | G A C E |
| F | B°7 | G# B D F |
| G | C6 | A C E G |
| G# | B°7 | B D F G# |
| A | C6 | C E G A |
| B | B°7 | D F G# B |
The C6 is "rest," the B°7 is "movement" (it contains the leading tone and the seventh of the dominant: it sounds like G7b9 without the root).
The minor version
C D Eb F G G# A B: chords Cm6 (C Eb G A) and B°7 (B D F G#). It is the color of the minor with a sixth, perfect for tunes like Summertime or Autumn Leaves on the i.
From the diminished to four dominants
Lowering a single note of a diminished chord by a half step gives a dominant seventh chord:
- B°7 (B D F Ab): B → Bb gives Bb7; D → Db gives Db7; F → E gives E7; Ab → G gives G7.
So a diminished chord "contains" four dominants a minor third apart. Harris used this to move the voices: from the diminished you "fall" onto the desired dominant.
Applications in comping
- Over a static chord (2 bars of C6): C6 – B°7/D – C6/E – B°7/F – C6/G… a melodic line harmonized in blocks that moves without changing function.
- Over a ii–V–I: Dm7 is "F6 with D in the bass": you can use the F diminished sixth scale on the ii (F G A Bb C C# D E with F6 and E°7), then the dominant, then C6.
- Drop 2: lowering the second voice from the top of the voicings in the table by an octave gives you open voicings for guitar or for a horn section.
- Parallel motion: Harris called "borrowing" the technique of borrowing notes from the diminished over a sixth chord, creating denser chords.
Listening example
Barry Harris's trio recordings (for example the Riverside and Prestige albums of the 1960s) and the videos of his workshops show the sixth–diminished block lines in intros and final choruses. The same principle was already in the block chord style of Milt Buckner and George Shearing.
Exercise for the producer
- In FL Studio, write the scale C D E F G G# A B in quarter notes, 120 BPM.
- Under each note add the three voices from the table: you have a 4-part harmonized line.
- Assign it to a horn ensemble (or a pad with a short attack) and use the line as a 1-bar fill before the chorus.
- Repeat in minor (Cm6 and B°7) and on F6 for the ii–V.
Related topics
The diminished seventh chord, passing diminished chords, voicing (drop 2), bebop scales, the ii–V–I in jazz.