Playing Over the Dominant 7th Chord

by Per Danielsson

Download this article (Printable Version)

A goal of mine when teaching jazz and improvisation is to clarify the theory. The sooner the students understand the basic theory, the sooner they can concentrate on the musical and creative aspect of improvisation. Even though jazz gives us more freedom compared with other forms of music, it is still important to understand the theory behind it to fully explore the genre's possibilities.

Perhaps the most confusing area is the treatment of the dominant seventh chord with its different alterations. The combination of alterations gives the dominant chord far more possibilities than the major and minor chords. Because of its dominant function, it's need to be resolved gives us the opportunity to experiment with that tension.

My goal with this article is to clarify and simplify the way we choose scales over chords, especially the dominant 7th chord.

One of the first things we learn in jazz improvisation is how to play over the ii-V-I progression by using dorian, mixolydian and major scales.

Dmin7	G7	CMaj7
Dorian	Mixolydian	Major Scale		Simplification of these three scales would be to think of them as the C major scale. ii-V-I in C, play C Major scale.
C Major Scale

Dmin75	G7913	Cmin7
Harm. minor	Harm. minor	Aeolian		Simplification of these three scales would be to think of them as the C harmonic minor scale. ii-V-I in C, play C Harmonic minor.
C Harmonic Minor

We have now discovered two scales that work on the dominant chord: Mixolydian and Harmonic minor.

Mixolydian


Harmonic Minor

The Altered scale is often the scale that confuses students the most. One reason for that is that the scale has many different names such as Altered scale, Altered Dominant, Super Locrian, or Diminished Whole Tone, to mention a few. Personally I like to call it Altered Dominant because it explains its function. Use this scale over an Altered Dominant chord.

To simplify this altered scale it helps to think Melodic Minor a half step up. In other words, an altered scale over a G7Alt chord is the same as an A Melodic Minor scale, played from G to G.

A melodic minor played from A to A


A melodic minor played from G to G.

If you have practiced all your scales, including melodic minor scales, this should be an easy scale to use. Listen to the tension it creates and when mastered, it will open up a whole new sound concept.

The Mixolydian BeBop scale is very useful over a non-altered dominant chord. It is a very melodic scale, especially when played descending. It differs from the Mixolydian with an added half step between the dominant seven and the root.

Diminished Scale

The diminished scale is another scale that creates tension. The only difference from the Altered Dominant scale is that it has a natural 5th and 13th. The diminished scale is also unique because it never resolves. There are two versions of the the diminished scale, half-whole and whole-half. Over the the dominant chord we use half-whole. The whole-half diminished scale is used over diminished chords. It's common to confuse these two diminished scales.

By using the above-mentioned scales there are endless possibilities on the dominant chord within a minor or major 2-5-1 progression. The five chord is like the last minute of a basketball game--everything is decided there. Make sure you practice these scales in all twelve keys. That way, your improvisation will become smooth and fluent.

This is a very basic explanation of these scales and their functions. But the main purpose is to show when to use them and to clarify the confusion about what goes with the dominant chord. Use the diagram below to practice all the different combinations of the scales. It is helpful to use a play-along CD that contains 2-5-1 progressions in all twelve keys. Listen carefully to how the different scales sound together and try to memorize the combinations you like.