Jazz Theory and Practice Module 2, a,b,c

Dominant-7th, Added-6th and Minor-7th Chords, The (II � V � I) progression

B. (1) Added sixth Chords; (2)Minor Seventh chords a. Basic structure of the added 6th chord.

The basic structure of the added 6th chord is really quite

simple: start with a major or minor triad, and add the note a major 6th above the root. The chord symbol is the name of

the triad with “6” added:

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In traditional harmony the added 6th chord is typically

analyzed as an inverted 7th chord (see next section). As

was indicated earlier, we will label the added 6th chord simply by adding “6” to the basic triad (major or minor), both as a

letter name and a Roman-numeral function:

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b. Relationship to the major and minor scale families The major triad with the added 6th fits all the scales in the major

scale family, but fits best with the major pentatonic scale (notice that the minor trichord is included in the chord):

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Copyright © 2012 Peter J. Clements

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The minor triad with the added 6th fits in both the Dorian and Jazz melodic minor scales:

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The opening measures of Gershwin’s Summertime use a

minor 6th chord:

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c. The added-6th chord in context; voicing

In Module 2c we will introduce the major-7th chord, which typically replaces the basic major triad in jazz harmony. As

we will discover, the major-7th chord is quite dissonant if the melody note is the chord root; in this instance the added-6th

chord is usually preferred. The basic major or minor triad is usually avoided at a cadence, because it typically sounds too

“thin”. The added 6th is one of several “colour notes” that can be added to a final chord, so that the sound is more

consistent with the rest of the harmony. The following

example shows how the tonic chord (I) can be coloured with various added notes in a II7 � V7 � I progression:

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The added 6th chord is most often voiced with all four notes, but the third or the fifth can be omitted:

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d. Minor-seventh chords

The minor 7th chords, together with the dominant 7th chords,

are the basic “bread and butter” of jazz harmony, and are common vocabulary in many other kinds of music (folk music,

hymn tunes, etc.) as well. Returning to an earlier example, with 7ths added to every chord in the major scale, minor 7th

chords fall naturally in three places:

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The basic structure of the minor 7th chord is a minor triad +

minor 7th, or, by stacking thirds: minor 3rd + Major 3rd + minor 3rd:

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If the notes of the minor 7th chord are arranged with the third of the chord on the bottom, it looks exactly like a major

added-6th chord:

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When is this chord a Dm7, and when is it an F6? To the jazz composer/arranger the distinction is usually clear enough. It

depends on how it fits logically in the overall chord progression, and in a jazz ensemble it may depend on what

other instruments are playing (especially the bass).

There are two common scales in the minor scale family that

are associated with the minor 7th chord: the natural minor (aeolian) and the dorian:

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In an improvisation around the minor 7th chord, the dorian is

often favoured because of the half-step that is adjacent to the 7th of the chord:

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Something to listen to: The added-6th chord was a favourite

colour in the “be-bop” style of the 1940s and 50s. The basic blues changes were typically added-6th rather than seventh

chords. Birds Feathers by Charlie Parker (look for the Parker original) is typical.

Minor-7th chords appear everywhere, especially as a part of ii7 �

V7 � I (see next section). There are a few minor key pieces where the minor-7th colour predominates: listen to Favela by

Antonio Carlos Jobim.

Return to the menu, and try the PLAY/SING and WRITE

exercises for Module 2b.