Introduction
A triad has three inversions; a seventh chord has four notes, so it has four: root position and three inversions, one with each chord tone in the bass. On guitar, the top four strings give a compact set of seventh-chord shapes that climb the neck. The third inversion, with the seventh in the bass, is especially useful because its bass wants to fall by a semitone.
Learning objectives
By the end of this lesson you will be able to:
- Name the four positions of a seventh chord by the note in the bass.
- Play G7 in root position and all three inversions on the top four strings.
- Use a third-inversion dominant 7 to lead the bass down by a semitone.
Concept
A seventh chord has four notes, so there are four ways to stack it, one with each note at the bottom. Using G7 (G B D F):
- Root position: G in the bass.
- First inversion: B (the 3rd) in the bass, written G7/B.
- Second inversion: D (the 5th) in the bass, written G7/D.
- Third inversion: F (the ♭7) in the bass, written G7/F.
The notes above the bass can come in any order. What names the inversion is only the lowest note.
On guitar, the top four strings (D, G, B, e) give one compact voicing of each, and they climb the neck in order: G7/D at the nut, G7/F around fret 3, root position around fret 5 and G7/B around fret 8. Played in sequence, you hear the same chord climbing.
Why the third inversion matters. A dominant 7 pulls towards its I chord, and the ♭7 wants to fall by a semitone. Put that ♭7 in the bass and the whole bass line falls by a semitone into the next chord: G7/F to C/E is F to E. It is a small, very satisfying move, and it gives you a smooth bass line where root-position chords would jump.
Visual explanation
e|---3-----0---|-|
B|---3-----1---|-|
G|---4-----0---|-|
D|---3-----2---|-|
A|-------------|-|
E|-------------|-|
1 2 3 4 e|---0-----3---|--0-----1---|-|
B|---1-----3---|--1-----1---|-|
G|---0-----4---|--0-----2---|-|
D|---2-----3---|--2-----3---|-|
A|-------------|------------|-|
E|-------------|------------|-|
1 2 3 4 1 2 3 4 Practical demonstration
Find the bass by ear.
- Play G7/D (xx0001). Pick the D string alone: D, the 5th. Second inversion.
- Play G7/F (frets 3-4-3-3). The D string at fret 3 is F, the ♭7. Third inversion.
- Play G7 at frets 5-7-6-7. The D string at fret 5 is G. Root position.
- Play G7/B at frets 9-10-8-10. The D string at fret 9 is B. First inversion.
The pull. Hold G7/F and let it ring. Then play C/E (frets 2-0-1-0 on the top four strings). Do it again, this time picking only the D string: F, then E. That single semitone carries the resolution.
Moving the set. All four shapes are movable. Five frets higher, the same four shapes give C7 and its inversions.
Guided exercises
Do these in order. Each one is small. Tick the ones you have practised.
1.Four G7s up the neck
5 min
- G7/D: open D, G and B strings with fret 1 on the high e (xx0001).
- G7/F: frets 3-4-3-3 on the top four strings.
- G7 in root position: frets 5-7-6-7.
- G7/B: frets 9-10-8-10.
- Play them in order up the neck and back, picking the four strings one at a time.
You have it when
- All four notes ring in each voicing.
- You can play the four shapes in order without looking them up.
2.Name the bass
3 min
- Play one of the four voicings at random.
- Pick only the lowest note and name it: G (root), B (3rd), D (5th) or F (7th).
- Say which inversion that makes: root position, first, second or third.
You have it when
- You name the bass note and the inversion correctly for all four shapes.
3.Resolve the third inversion
4 min · 60 → 72 BPM
- Play G7/F, then C/E on the top four strings (frets 2-0-1-0). Listen to the bass fall from F to E.
- Play the progression C, G7/F, C/E, F, one bar each, using the top four strings for every chord.
- Play the same progression with root-position G7 and compare: which bass line is smoother?
You have it when
- You can hear the F to E semitone in the bass.
- The progression flows without a jump in the bass.
Tempo recommendations
No metronome for the shapes. For the progression, use 60 BPM with one chord per bar, four light strums or a slow pick across the four strings.
| Exercise | Start | Target |
|---|---|---|
| Resolve the third inversion | 60 BPM | 72 BPM |
Common mistakes
- Letting the A and low E strings ring. These voicings use only the top four strings. Pick or strum from the D string, or mute the lower strings with the thumb.
- Naming the inversion by the top note. Inversions are named by the lowest note. The top note can be anything.
Musical application
Inversions of seventh chords let a bass line move by step under a progression, which is how pianists and arrangers make harmony flow. In your own songs, try replacing a root-position V7 with its third inversion when the next chord is I in first inversion.
Practice assignment
Short version (10 minutes)
Play the four G7 voicings up and down the neck, naming each bass note.
Standard version (about 30 minutes)
Do all three exercises, then build the four voicings of C7 by moving each G7 shape up five frets.
Recap
- Four chord tones, four bass notes: root position, 1st, 2nd and 3rd inversions.
- On the top four strings, G7 climbs: /D at 0, /F at 3, root at 5, /B at 8.
- Third inversion has the 7th in the bass, which wants to fall a semitone.
- The shapes are movable: up five frets for C7.
Completion criteria
You are ready to move on when you can honestly say:
- I can play a dominant 7 chord in root position and three inversions.
- I can name the inversion of a seventh chord from its bass note.
- I can use a third-inversion V7 to lead smoothly to I.