Guitarists of all stripes often look for ways to enhance basic chord progressions with some colorful chords. Adding the ninth note of a chord’s underlying scale is a common but tasty way to add interest and color to a chord without changing its basic quality or function. In this lesson, we’ll see that the ninth note of the major scale fits right in whether we’re playing bluesy dominant chords or the typical major- and minor-seventh chords that are found in the acoustic stylings of folk, jazz, or Latin music.
Add9 Chords
To better understand what ninth chords are, let’s start by looking at the C-major scale in Example 1 , which climbs all the way up past the upper root to the ninth. You’ll see that the ninth is one octave above the second note of the scale and has the same note name (D, in this case). This is a handy shortcut to use when you want to identify the ninth of any chord: it’s just one whole step above the root.
Adding the ninth to any major triad (the first, third, and fifth notes of a major scale) yields an add9 chord . Example 2 shows two useful Cadd9 voicings—the first uses the open high E string, and the second uses the high G on top. Add9 chords are nice substitutes for common major triads and are heard in music as wide ranging as the Police’s “Every Breath You Take,” Janis Ian’s “Jesse,” and Ralph Towner’s “Icarus.” Even if we change roots and mix up the order of the notes, as in Example 3 (which shows fingerings for A, D, and E add9 chords), the sound of the add9 is stable in a way that is similar to a major triad.
Dominant Ninths
You’ll notice that add9 chords don’t have much “grit” behind them—they sound an awful lot like major chords, with just a hint of extra flavor. By adding a flatted seventh note to the mix, however, we get a great, bluesy, dominant-ninth chord. In Example 1, you can see that the seventh note of the C-major scale is B. To find the flatted seventh, lower the seventh note of the major scale by one half step—Bb in the key of C. Adding a Bb to the Cadd9 chord gives you a C9 chord. The common fingering shown in Example 4 balances the dominant sound of the flatted seventh and the added color of the ninth. This movable voicing can be played up and down the neck to make any ninth chord. You’ll recognize the sound of this chord if you’ve listened to any blues, funk, and R&B (just think of the opening chord to “Kiss” by Prince).
Since dominant-ninth chords are really just dominant-seventh chords with an extra colorful note on top, they can make great substitutes for the dominant-seventh chords you already play. One great way to compare these two chord types is to play through songs you already know and substitute ninth chords wherever you would normally play a dominant seventh. Example 5 shows a progression full of dominant-seventh chords, each resolving to either a major chord or another dominant. Compare this to Example 6 , which has the same progression but uses ninth chords in place of seventh chords (and an add9 to brighten the C-major chord).
To make the best use of ninth chords in a progression, it helps to know a few different fingerings so you don’t have to leap around too much, chasing one movable shape around the neck. Example 7 shows another take on the progression in Examples 5 and 6 with different ninth-chord voicings that allow for smoother voice leading from one chord to the next. The root doesn’t always show up in the bass in these chords but the important notes are all accounted for, so they still work well in the context of the progression.
