In plain words
Everything is minor thirds, Barry told Eli Yamin: the minor third is the most important interval of all. The whole-tone scale gives you major thirds, but the diminished chord is built of minor thirds, and that is what makes families. The major keys of C, E♭, F♯ and A, the four notes of one diminished chord, are brothers and sisters: C’s family is E♭, E♭’s is F♯, and so on.
Jazz theory, part 1: key families a minor third apart4:585:35The minor-third family0:00
The same goes for dominants. Lower each note of a diminished chord a half step in turn and you get four dominant sevenths, also a minor third apart; from C diminished they are B7, D7, F7 and A♭7. Barry called them brother and sister, children who grew up together, and asked who you play with first: your brothers and sisters.
Jazz theory, part 3: four dominants from one diminished8:369:10Student performances and coaching32:0733:51Believe: a talk to musicians19:4120:15
Grouping keys this way shapes practice. Barry put Eli through a ‘torture test’ in four keys, C, E♭, F♯ and A, one after the other, so that each key is learned with its relatives: practise C and you practise E♭ too, because they are related.
Jazz theory, part 1: key families a minor third apart2:303:454:234:585:35
For Barry this is what the diminished scale is really about. Defining it as half step, whole step tells you nothing; what it gives you is families, and someone who does not know that four dominants come from every diminished and belong together gets nothing from it.
The last train to Monk: an interview30:48Believe: a talk to musicians19:4120:15
Step by step
Stack minor thirds from a key’s tonic to find its family.
C’s family- C
- E♭
- F♯
- A
Jazz theory, part 1: key families a minor third apart4:58The minor-third family0:00
Those four notes are one diminished chord, and there are only three diminished chords, so the twelve keys fall into three families of four.
D♭’s family- D♭
- E
- G
- B♭
D’s family- D
- F
- A♭
- B
Jazz theory, part 1: key families a minor third apart4:58Student performances and coaching29:53Howard Rees, Chord Explorations ¶8
For the dominants: lower each note of the diminished chord in turn; the lowered note is the root of a dominant seventh, and the four are one family.
Roots of the four dominants from C dim7- B
- D
- F
- A♭
Jazz theory, part 3: four dominants from one diminished8:36Student performances and coaching32:07
How he said to practise it
Run the four keys of a family in one exercise, as Barry did with Eli Yamin: go up the chords of C from the one to the three, take a minor chord that is the two of E♭, land on E♭, and carry on through F♯ and A back to C.
Jazz theory, part 1: key families a minor third apart3:053:454:23jazzguitar.be members (usernames kept per post), Barry Harris ‘Playing in 4 Keys’ concept (jazzguitar.be forum thread) ¶33
Practise the four dominants of each family and run them into each other; if you cannot run A7 into C7 or C7 into A7, Barry said, you are not practising the music.
In Barry’s words
Each one plays from the moment he says it. Every other moment he teaches it is listed below.
Everything is minor thirds. Minor thirds is the most important thing of all.
The family is minor thirds. C is the family [of E flat]...
They’re brother and sister. Who do you play with first? Your brother and your sister... You play with your family first.
All of you should be practicing those four dominants. They’re brother and sister, they grew up together.
Where this comes from
Everything above is drawn from these. Open any one to check it.
Every moment he teaches it12 moments in 7 recordings
Each time opens the transcript there; the video plays when you are online.
Jazz theory, part 1: key families a minor third apart
- 4:58
Everything is minor thirds: C, E♭, F♯ and A are brothers and sisters, one family.
- 2:30
Starts a ‘torture test’ for Eli Yamin: playing in four keys.
- 3:45
Steers Eli through the keys, naming the two and one of each new key.
- 7:25
Second round through the keys; Barry notes Eli is getting to know each of them.
The minor-third family
- 0:00
Rome 2016: the family is minor thirds; C, E♭, F♯ and A are one family.
Jazz theory, part 3: four dominants from one diminished
Student performances and coaching
Believe: a talk to musicians
- 19:41
Four dominants from every diminished are brother and sister; half-whole definitions miss this.
The last train to Monk: an interview
- 30:48
What the diminished scale gives us is families, which teachers do not know.
Introducing the sixth diminished scale
- 13:41
Names D7’s relatives, F7, A♭7 and B7; their triads in the chord sound right: family.
From the lessons2 lessons, 6 points
Notes taken from Barry’s classes, each tied to the moment it comes from.
Minor thirds and the diminished family
- Idea
The twelve notes divide into two whole-tone scales and into three diminished seventh chords, and nothing goes beyond those twelve. Barry reminds the class of this as a basic fact to know before working with diminished chords.
Jazz theory, part 2: drop voicings4:58
- Idea
Everything is minor thirds, Barry says; it is the most important interval of all. The whole-tone scale gives you major thirds, but the diminished chord gives you minor thirds. So the major keys a minor third apart, C, E-flat, F-sharp and A, are brothers and sisters: one family. C major’s family is E-flat, F-sharp and A, and you practise them together.
Jazz theory, part 1, with score4:23
- Exercise
In a class in Bilbao, given through a Spanish interpreter, Barry described the diminished scale as the four notes of the diminished chord combined with the roots of the dominants it relates to. Each diminished note therefore sits between two of those roots: E-flat, for example, is surrounded by D and F. Exercise: from a diminished note, move to a neighbouring note and come back to the original, and do this through every inversion of the diminished chord.
- Idea
The first way to modulate, Barry says, is with the diminished chord. He calls the diminished the ruler: you may think you are heading for G, but the diminished can say no and take you to F, B-flat or C instead. One diminished chord can lead you into several different keys.
11 March 2016, part 2: the diminished as ruler2:39
Swapping dominants within the family
- Idea
Barry called the minor third the most important interval of all. Major thirds are good too, since the whole-tone scale is built from them, but the diminished chord gives you minor thirds. The major keys C, E-flat, F-sharp and A are brothers and sisters, one family: C’s family includes E-flat, E-flat’s includes F-sharp, and so on.
Jazz theory, part 1: key families a minor third apart4:58
- Idea
Barry treated E-flat 7 and C7 as one family: E-flat 7, he said, stands for C7, and when he plays a half-diminished he plays E-flat 7 to C7, because E-flat 7 gives the G half-diminished. He also linked C7 and A7 to E half-diminished. From the E-flat 7 he went into F-sharp 7 to get into the tritone, which he said starts something else altogether. The four dominants of a family, he said, play with each other first.
In writing5 notes
What his interviews, his students’ class notes and other teachers’ articles add.
Vera Marijt draws the conclusion for one family: C7, E♭7, G♭7 and A7 all come from the D♭ diminished chord and are related as family.
Howard Rees pairs Barry’s family line with a practical use: the four dominants that come from one diminished seventh are related, so they can stand in for one another, or one can be the basic voicing with the others added to it to make an extended dominant.
Howard Rees, Evolutionary Voicings, Part I: Barry Harris Keeps Things Movin’ ¶5Howard Rees, Evolutionary Voicings, Part I: Barry Harris Keeps Things Movin’ ¶13
Rees builds practice on the families: run each dominant scale into its three relatives over common progressions; with the three diminished chords you cover all twelve keys without circle-of-fifths drills.
Howard Rees, Chord Explorations ¶8Howard Rees, Chord Explorations ¶9Howard Rees, Chord Explorations ¶41
A jazzguitar.be member writes out the four-key exercise as chords: Cmaj7 Dm7 Em7 Fm7, E♭maj7 Fm7 Gm7 A♭m7, G♭maj7 A♭m7 B♭m7 C♭m7, Amaj7 Bm7 C♯m7 Dm7, back to Cmaj7. The fourth chord, made minor, is the two of the key a minor third up.
jazzguitar.be members (usernames kept per post), Barry Harris ‘Playing in 4 Keys’ concept (jazzguitar.be forum thread) ¶33jazzguitar.be members (usernames kept per post), Barry Harris ‘Playing in 4 Keys’ concept (jazzguitar.be forum thread) ¶34jazzguitar.be members (usernames kept per post), Barry Harris ‘Playing in 4 Keys’ concept (jazzguitar.be forum thread) ¶35jazzguitar.be members (usernames kept per post), Barry Harris ‘Playing in 4 Keys’ concept (jazzguitar.be forum thread) ¶36jazzguitar.be members (usernames kept per post), Barry Harris ‘Playing in 4 Keys’ concept (jazzguitar.be forum thread) ¶37jazzguitar.be members (usernames kept per post), Barry Harris ‘Playing in 4 Keys’ concept (jazzguitar.be forum thread) ¶38
One member of a jazzguitar.be study group on Alan Kingstone’s guitar book reads it as built around three families: brothers and sisters within a family, ‘away and home’ between families, and diminished chords used to pass smoothly from one family to the next.
jazzguitar.be members (usernames kept per post), Kingstone/Harris Harmonic Method for Guitar ¶359
How other teachers explain it7 videos, 10 series episodes
Barry’s students, and their students, teaching it their way. A second opinion, not Barry.
- Things I’ve Learned from Barry Harris Episode 10 Playing with the Family of Dominants
Episode 10: playing with the family of dominants.
11 min, transcript On YouTube
- Barry Harris Method: The “Family” Of 4 Dominant 7th Chords ()
The family of four dominant 7th chords.
10 min On YouTube
- My Chat With Chris Parks From Things I Learned From Barry Harris
Finds B diminished’s family by lowering one note at a time: B♭7, E7 and so on.
62 min, transcript On YouTube
- Little Labyrinth 13: Family Connections ( Barry Harris )
11 min On YouTube
- Little Labyrinth 75: Learning Family from “Things I Learned from Barry Harris”
14 min On YouTube
- Barry Harris’ “Brother & Sister Chords”, The Four Dominants & Bartok’s Axis System | Piano Tutorial
Brother and sister chords and the four dominants, compared with Bartók’s axis system.
7 min On YouTube
- Brother chords - Barry Harris
9 min On YouTube
In the teaching series
Episodes on this idea in the long series by other teachers. Each name opens that whole series in order.
The Labyrinth of Limitations
- 5 levels of a turnaround in any key with scales of chords YouTube
- Brothers and sisters with Barry Harris harmony YouTube
- Practising the family YouTube
- Brothers and sisters blues YouTube
- Little Labyrinth 15: a movement exercise through the family YouTube
- Little Labyrinth 34: the ugliest duckling YouTube
- Little Labyrinth 37: modulation with movement YouTube
Where the accounts differ1 point
Who are the brothers and sisters? In the classes Barry uses the phrase for the four keys a minor third apart and for the four dominants of one diminished chord. In words Howard Rees attributed to Barry in 2001, quoted by de Lima, it is the three diminished chords themselves that are siblings, known by their DNA.
Jazz theory, part 1: key families a minor third apart4:58Jazz theory, part 3: four dominants from one diminished9:10Brian Jude de Lima, Reanimating Dissonance: Cultivating the Antecedents of Barry Harris’ Concept of Movement as a Multidimensional Pedagogical Tool for Ontario Post-Secondary Jazz Curricula ¶1396
Read further3 links
These open on the web.
Free to read
- Howard Rees, Jazz Workshops
— Free article by Howard Rees with Barry’s brothers-and-sisters line and the four related dominants in notation.
Books and paid courses
- Howard Rees, ‘Chord Explorations’, Keyboard Magazine Mar 2001 (chords come from dominant scales; practise the 12 keys through the 3 dominant families)
student (Howard Rees) — Free article by Howard Rees: practise all twelve keys through the three dominant families instead of the circle of fifths.
- jazzguitar.be ‘Blues theory through the Barry Harris lens’ (brothers and sisters, minor 6)
players — Forum thread applying brothers and sisters to the blues.