38 The Tonic, Subdominant, and Dominant Families as Tall Chords

In general, tall chords in jazz function in the same way as the traditional triads or seventh chords covered in the Diatonic and Chromatic Harmony sections.

A solid knowledge of the spelling of tall chords on any root is essential to the understanding of jazz chord progressions.

TONIC function

The innovations of composers from the Impressionist era including Debussy and Ravel (and later on Gershwin) led to the coloring and enrichment of the major and minor tonic triads through extensions: major 6, major 7, major 9. Additionally, the major triad can employ the augmented 11 (11).

subdominant function

The subdominant function in jazz harmony uses ii⁷ rather than IV.  (Jazz musicians refer to this as the “subdominant” since it is a combination of the subdominant and supertonic elements.)

The extensions of the supertonic seventh chord are 9, 11, and 13.

For the use of the IV or iv chord, refer to the turnarounds and short progressions and the chapter on the blues.

dominant function

The dominant seventh chord is embellished through alterations of the perfect 5^th (5, 5) and a large number of extensions (9, 9, 9, 11, 11, 13, 13).

The upper three notes of many of the dominant and some of the tonic and subdominant tall chords form a seemingly unrelated triad, at times spelled enharmonically. The resulting structure is a polychord or bi-chord (see chapter on 20th Century Compositional Techniques) and can be labeled in either of the two ways shown above the chord. The lower chord reflects the quality of the chord and governs its resolution, while the upper triad provides a colorful extension. Jazz pianists and arrangers usually divide the two chordal elements between the two hands or between two groups of instruments.

Simple and Compound Intervals
as Alterations and Extensions of Tall Chords

To facilitate the identification and spelling of tall chords, memorize the interval chart below. A compound interval is a simple interval extended by a perfect octave (P8).