12 Scales To Play Over A Dominant 7th Chord

What's a Dominant 7 Chord?

The first thing to do before starting exploring the twelve different scales shown in this lesson is to understand how to build a basic dominant 7th chord and what its role is.

A Dominant 7th chord is made up of a root / tonic (1), a major third (3), a perfect fifth (5) and minor seventh (b7). It is one of the most versatile chords.

It is considered as a major chord because of the major third (3).

Indeed, the 3rd tell us if the chord is minor or major. The minor seventh (b7) indicates whether the sound wants to move or not (resolve) to another chord.

Usually dominant chords tend to resolve to a chord down a perfect fifth (or a chord up a perfect fourth).

Dominant 7th Chord Basic Guitar Positions

Because it is very important to make the association between scales and chords, you must be able to play several basic dominant 7th chord positions on guitar.

Here are three basic guitar positions that will help you. 

These guitar diagrams represent a D7 chord. Please note that the root is the orange note, the minor seventh is the green note and the major third is the note in blue.

The principle is the same for the two other diagrams.

Any jazz guitar student must be able to play these three guitar positions in twelve keys and make the link between them and the scales below.

D7 guitar position 1, root on the sixth string. The black note is the fifth, free to you to play it.

D7 guitar position 2, root on the fifth string. There is no fifth in this diagram, the black note is the octave of the main root.

D7 guitar position 3, root on the fourth string. The fifth is the black note.

Mixolydian Mode

The Mixolydian scale is surely the most obvious choice when you want to improvise over dominant 7th chords.

It is built with a root (1), second (2), third (3), perfect fourth (4), perfect fifth (5), sixth (6) and minor seventh (b7). 

Also called dominant 7th scale, it is the fifth mode of the major scale related to the fifth chord of the harmonized major scale.

Indeed when you stack the 1, 3 , 5 and b7 of the Mixolydian scale you get a dominant 7th chord.

Dominant Bebop Scale

The dominant bebop scale is an eight-note scale (octatonic).

It contains the same notes as the previous Mixolydian mode including a chromatic passing tone, a major seventh (7), between the minor seventh (b7) and the root (1).

Notive that this passing tone should never be played on the downbeat, but preferably on the upbeat.

The chart below shows you how to build the G dominant bebop scale.

You can notice the chromatic passing tone is the yellow note (Bb).

Lydian Dominant Scale

The Lydian dominant scale is the fourth mode of the melodic minor scale.

You can think it as the Mixolydian mode with a raised fourth (#4) or raised eleventh (#11) also used to be called a b5.

As you will have understand, the Lydian dominant scale is designed to work over 7#11 chords or any dominant 7th chord when you want to highlight the #11.

Mixolydian b13 Scale

The Mixolydian b13 or b6 scale is the fifth mode of the melodic minor scale.

In comparison with the Mixolydian mode it has a flat (b6) instead of a natural sixth, hence its name.

Playing this scale over a dominant 7th chord brings a little bit of tension and has a very melancholic sound.

Phrygian Dominant Scale

The Phrygian dominant scale, also called altered Phrygian scale is the fifth mode of  the harmonic scale.

It has a very particular sound because of its minor second (b2) and its minor sixth (b6).

This scale can be applied to dominant 7th chords when you want to produce a 7b9b13 sound in your jazz improvisations.

Altered Scale

The altered scale (or superlocrian scale) is the seventh mode of the melodic minor scale.

It contains four altered tones that bring tension, b9,#9, #11 b13, meaning that is can be used over 7#9, 7b9, 7b5, 7#5, 7#11, 7b13 and many other altered chords.

Major Pentatonic Scale

The major pentatonic scale as its name implies, is made up of five notes, it is surely the easiest scale to play over a dominant 7th chord.

It produces a ninth (9) and a thirteenth (13) sound. 

Minor Pentatonic Scale

The minor pentatonic scale is played over dominant 7th chords when you want to bring a blues feel to your jazz lines.

As explained at the beginning of this lesson, dominant 7th chords contain a major third (3) and minor pentatonic scales has a minor third (b3). 

Mixing major and minor tonality, the clash of the minor and major thirds, it is that blues thing. 

Major Blues Scale

The major blues scale is a hexatonic scale it contains six notes including an added minor third (b3 / b10) between the second (2) and the major third (3).

This is actually the major pentatonic scale with a passing tone.

Whole-Tone Scale

The whole-tone scale belongs to the family of symmetric scales, which consist of repeated symmetric intervals.

As its name implies, the whole tone scale is made of a succession of whole tone intervals, the octave is divided in six equal parts. 

It contains a raised eleventh (or #11) and a raised fifth (#5) that can bring interesting tensions and funny new colors to your jazz guitar solos. 

Dominant Diminished Scale

The dominant diminished scale also known as half-tone / whole-tone scale is a symmetric scale built by alternating half-steps and whole-steps.

You can play it over dominant 7th chords, theoretically 7b9 chords, when you want to produce interesting tensions and create outside sounds in your jazz and blues guitar improvisations.

This way you highlight the b9, #9 and #11.

Chromatic Scale

The chromatic scale contains the twelve musical notes where every note is a semi-tone (or half-step) apart.

As you can see in the chart below the chromatic scale has no intervals larger than a semi-tone.

Unlike other scales, it doesn't have chords associated with. 

The first approach to familiarize yourself with is to play each consecutive frets, up or down on the guitar. 

This symmetric scale is rarely played over an entire guitar solo, but maybe useful when mixed with more conventional dominant scales.

Conclusion

The best way to take the most of this lesson is to experiment each scale by playing them over a dominant 7th backing track.

Try to play them ascending and descending, try to create fluid lines using arpeggios and patterns.

Try to incorporate these lines into common jazz progressions as minor and major II-V-I, blues, turnarounds, bridges.

Remember that playing the corresponding chord after or before playing each scale is an excellent way to develop your musical ear.