Mixolydian Mode

Mixolydian is a major scale with a flatted seventh. It's the dominant sound — the sound of a chord that wants to resolve but is comfortable where it is. Rock, blues, and country guitarists use it constantly without naming it: any time you play a major scale but hit that ♭7 note, you're in Mixolydian. It's also the natural scale for improvising over dominant seventh chords in jazz — the scale that contains all four chord tones plus the most usable extensions.

Construction

The fifth mode of the major scale — starts on the 5th degree.
G Mixolydian = C major scale starting on G:
G A B C D E F G

Formula:      1  2  3  4  5  6  ♭7
Step pattern: W  W  H  W  W  H  W

Compare to G major (Ionian): G A B C D E F# G
The F is natural in Mixolydian (F# in Ionian) — the ♭7 is the only difference.

Mixolydian in Common Keys

Mixolydian root	Notes	Parent major key	The ♭7
G Mixolydian	G A B C D E F	C major	F
D Mixolydian	D E F# G A B C	G major	C
A Mixolydian	A B C# D E F# G	D major	G
E Mixolydian	E F# G# A B C# D	A major	D
C Mixolydian	C D E F G A B♭	F major	B♭
F Mixolydian	F G A B♭ C D E♭	B♭ major	E♭

Mixolydian Over Dominant 7th Chords

This is the core application. A G7 chord (G B D F) is entirely contained within G Mixolydian, plus the scale provides the natural extensions:

G7 chord tones: G  B  D  F
G Mixolydian:   G  A  B  C  D  E  F
                   ↑        ↑     
                   9th      13th (extensions)
                         ↑
                         11th (use carefully — can clash with B, the major 3rd)

Scale degree → chord extension:
  A = 9th (major 9th — usable, warm)
  C = 11th (perfect 11th — avoid in jazz unless substituting; clashes with major 3rd B)
  E = 13th (major 13th — very usable, bright)

Extension	Quality	Over G7	Use?
9th (A)	Major 9th	Warm, smooth	Yes — standard
11th (C)	Perfect 11th	Slightly tense against B (major 3rd)	With care, or use as sus4
13th (E)	Major 13th	Bright, open	Yes — standard

Sound and Character

Major but grounded, earthy, with a bluesy edge. The ♭7 prevents the leading tone pull of the major scale — without F#, G Mixolydian doesn't have the half-step pull toward the octave. This gives it a hanging, relaxed quality that the major scale's urgency lacks. Songs that sit on one dominant chord for an extended period — blues vamps, funk grooves, rock riffs — often imply Mixolydian even if nobody names it.

Rock and Blues Examples

Song	Artist	Mixolydian key
"Sweet Home Alabama"	Lynyrd Skynyrd	G Mixolydian (D-C-G vamp)
"Norwegian Wood"	The Beatles	E Mixolydian
"Hey Joe"	Jimi Hendrix	E Mixolydian (C-G-D-A-E vamp)
"Sympathy for the Devil"	Rolling Stones	E Mixolydian
"What I Got"	Sublime	D Mixolydian
"Fire on the Mountain"	Grateful Dead	Mixolydian vamp

Mixolydian in Jazz

Over unaltered dominant chords (G7, A7, D7), Mixolydian is the default scale. When the chord calls for altered extensions — G7♭9, G7#11, G7alt — you move to the altered scale, Lydian dominant, or other altered options. Mixolydian is the "natural dominant" sound; the altered scales are for maximum tension before resolution.

G7 in a ii-V-I (Dm7-G7-Cmaj7):
  If you want smooth: G Mixolydian throughout G7
  If you want tension: G altered scale (maximises dissonance before Cmaj7)
  If you want middle ground: start Mixolydian, shift to altered on last beat of G7

References

Levine — The Jazz Theory Book
Bergonzi — Inside Improvisation Series
jazzguitar.be — Mixolydian Mode ↗