There is a basic guide for improvisation that says :

There are some exceptions to this rule. Notably the use of the Minor pentatonic and Blues scales over the whole blues progression (as we have seen in previous lessons). But in general this guide holds true.

For improvisation over the dominant 7th chord, the most commonly used scale is the Mixolydian mode.
The Mixolydian mode is easiest described as a major scale with a flattened 7th note.

If you have a closer look at the C Mixolydian mode, you will notice that it contains the same notes as the F major scale. The Mixolydian mode only starts on a different tonic note (C).

Audio 8.2

Likewise the F Mixolydian mode consists of the same notes as the Bb major scale,

Audio 8.3

and the G Mixolydian mode uses the same notes as the C major scale.

Audio 8.4

Therefore a Mixolydian mode can be formed from any major scale by starting on the 5th note of that major scale.

Although the major scale and related Mixolydian mode use the same notes, they still sound differently because the semitone intervals of the scale and mode occur at different points in relation to the tonic. This is a vital difference.

In a major scale the semitones are between notes 3 and 4, and between 7 and 1.

In the Mixolydian mode they occur between 3 and 4, and between 6 and b7.

In Mixolydian Blues the appropriate Mixolydian mode is used for each individual chord of the blues.
For the Blues in C use :

Audio 8.5

Play-along tracks for the Blues in C (all instrument use the C, F and G Mixolydian modes).

• C- instruments use bblc.mid (or any other track in C)
• Bb- instruments use bblbb.mid (or any other track in Bb)
• Eb- instruments use bbleb.mid (or any other track in Eb)

Bb-instruments also practise above routine for the blues in G and in A.

Eb-instruments also practise above routine for the blues in D and in E.

There are no 'blue notes' in the Mixolydian modes that clash with the blues chords. The b7 in the mode always coincides with a corresponding chord tone.
Blues melodies and improvisations that use Mixolydian modes have therefore a very clean and clear sound which contrasts sharply with the usual 'dirty blues'.

The Mixolydian modes can provide a strong musical contrast to the blues scale in a blues improvisation. This is most useful when soloing for several choruses. You can start for example with a couple of choruses using the minor pentatonic, follow it by adding the 5b (blues scale), then come clean with a few choruses using Mixolydian modes.

Come with Me features a blues melody entirely composed of notes from the three underlying Mixolydian modes.

Melody

Play-along tracks for the Blues in C (all instrument use the C, F and G Mixolydian modes).

• C- instruments use bblc.mid (or any other track in C)
• Bb- instruments use bblbb.mid (or any other track in Bb)
• Eb- instruments use bbleb.mid (or any other track in Eb)

• Take 1 (10 choruses) - : I play the first 2 bars of each 4-bar phrase, you play the following 2 bars.

• Take 2 (10 choruses) - : You play the first 2 bars of each 4-bar phrase, I play the following 2 bars.

• Take 3 (10 choruses) - : I play the first 4 bars, you play the following 4 bars.

• Take 4 (10 choruses) - : You play the first 4 bars, I play the following 4 bars.

Improvise using Mixolydian modes only.     Swing style.

You can introduce some 'dirty blues' into the Mixolydian modes by adding a few chromatic passing notes.

The blue notes (b3, b5 and b7) for each of the three chords are especially effective.
The b7 is already in the Mixolydian mode, just add the other two notes :

Audio 8.6
(Click on anu staff to hear its Audio)

Other chromatic passing notes can also be used.
Approaching scale tones from a semitone above or below is appropriate for the Blues, as it simulate the 'bending' of notes, a prominent feature of the earliest blues singers.

This Ruler works in the same way as the Rulers from previous Lessons.
Use the Mixolydian mode Ruler shown below to find the notes of the Mixolydian mode in any key by aligning the Tonic note of the required mode on Note Names ruler with the '1' on the MIxolydian mode ruler.

For example, to find the E Mixolydian mode :

1. first align 'E' with '1'

2. then read the E Mixolydian mode : E F# G# A D C# D E

A.
Convert these major scales into Mixolydian modes by changing one note in each scale.

1. G A B C D E F# G
2. E F# G# A B C# D# E
3. Bb C D Eb F G A Bb
4. D E F# G A B C# D
5. B C# D# E F# G# A# B

1. G A B C D E F# G
2. E F# G# A B C# D# E
3. Bb C D Eb F G A Bb
4. D E F# G A B C# D
5. B C# D# E F# G# A# B

1. C F Eb Bb G A D
2. A C G F D E B
3. Ab Eb Bb F G D C
4. F# D C A B E G
5. A C F Bb D E G