Bill Irwin Pop Organ Workshop - 9th Chord Substitution, Part I

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In my column for December '76, I explained moving 9th chords in connection with harmonizing whole-tone runs. In this session, we're going to use the moving 9th chords to reharmonize melody notes, which in turn will lead to creating introductions, harmonic fills, endings, and simple harmonic substitutions in specific places.

First, a quick review of moving 9ths, to save you having to dig through your back issues. A moving 9th chord is a 9th chord played in root position with the 5th omitted. Omitting the 5th not only facilitates movement, it also allows the chord to be used to accompany a flatted 5th or sharped 5th in the melody without altering the accompanying chord. These examples illustrate the moving 9th chord shape:

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Practice moving 9ths as follows: Play the left-hand chords and bass pedals up and down one octave chromatically, naming each chord out loud. (The verbal identification will help because in chromatic practice physical movement tends to take control, so that you tend to play automatically without truly identifying each chord.) Next, practice the 9th chords in whole-tone movement up and down one octave, starting first on C9 and then on Db9. A physical approach to finding isolated moving 9th chords is to play the root in the bass pedals, then find the 3rd step (two whole-steps above the root) with the 5th finger of the left hand, and have the 2nd and 1st fingers play the keys that are one whole-step on either side of the root (the 7th and the 9th). Practice this technique before going on.

A simple introduction to the use of moving 9th chords is to follow this rule: when a melody note is sustained on the 5th, 6th, or b7th step of an indicated 7th or 9th chord, substitute the moving 9th a half-step above the original root and resolve to the 9th chord on the original root. Examples:

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Note that the G which is the 5th of C7 becomes the b5th of Db9, the A which is the 6th (or 13th) of C9 becomes the #5th of Db9, and the Bb which is the b7th of C7 becomes the 6th (or 13th) of Db9.

This substitution, or reharmonization with resolution, enhances the original melody note and provides an additional chord upon which melodic embellishments can be built. Learn to quickly associate melody notes with steps of the indicated chord in order to recognize the scale steps that can be used for this substitution. Go through some of your favorite lead lines looking for opportunities to use the substitution.

Next, we can easily reharmonize melodies that move in a close or scale-like manner by thinking of each melody note as a numbered step in an unknown 9th chord. At first, each melody note will be given the same number, which will give us a series of moving 9th chords in parallel motion. We will use all the steps of a 9th chord, i.e. the root, 3rd, 5th, 7th, and 9th. In addition, because the 5th is omitted from the moving 9th shape, we can designate a melody note as the b5th, #5th, or 6th (13th) step of some 9th chord—which will give us eight possible reharmonization of a melody almost instantly!

Let's start with a simple example I've used in my workshops:

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If I said that the notes C, E, and G were all the first steps (roots) of unknown 9th chords, you should find it easy to identify the chords as C9, E9, and G9. If we decided to identify each melody note as the 3rd of some 9th chord, the root of the chord below the C would be Ab (two whole-steps below), making the chord Ab9. In the same way, the E would be the 3rd of C9 and the G would be the 3rd of Eb9. The same process of reasoning can be used on the melody for all eight numbered chord steps we use. The following illustration shows all eight reharmonization of the original three-note melody. Play through the examples slowly, holding the left-hand chords as long as possible before moving rapidly and cleanly to the next chord.

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Next month, I'll conclude this short treatise on substitution using moving 9th chords with some examples of contrary motion between melody notes and the accompanying chords. Meanwhile, if you can get the lead line to the show tune "Sometimes I'm Happy," the two-measure phrase behind the title lyric is played eight times, providing a perfect opportunity to use a different set of 9th chords each time! Look for other opportunities, and we'll get together next month with more information.

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