Also written GdimMaj7, GdimM7 or G°M7
G diminished major 7th contains G, B♭, D♭, and F♯. The default GdimM7/D♭ inversion uses an open G string and a compact three-fret cluster.
The same three notes, with a different one in the bass.
G diminished major 7th is built from the formula 1, ♭3, ♭5, 7. The major 7th interval between G and F♯ gives it a sharp leading tone. Compare it to G minor 7th flat 5th, which lowers the 7th to F.
G diminished major 7th works as a passing chord in G minor or G major contexts. Use it to lead into G minor or G major. Its tense sound suits jazz and gypsy minor lines.
The GdimM7/D♭ inversion keeps the bass on D♭, which softens the root. The GdimM7/F♯ inversion puts the major 7th in the bass for a brighter edge.
G diminished major 7th is played in open position as 0 1 2 1: index finger on the C string at fret 1, ring finger on the E string at fret 2 and middle finger on the A string at fret 1. The G string rings open.
Tip — The ring finger must reach the 2nd fret on the E string while the index and middle hold the 1st fret.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (G) | open | — | G (1) |
| 3 (C) | 1 | 1 | D♭ (♭5) |
| 2 (E) | 2 | 3 | F♯ (7) |
| 1 (A) | 1 | 2 | B♭ (♭3) |
G diminished major 7th is played at the 3rd fret as 3 6 3 4: index finger on the G string at fret 3, pinky finger on the C string at fret 6, middle finger on the E string at fret 3 and ring finger on the A string at fret 4.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (G) | 3 | 1 | B♭ (♭3) |
| 3 (C) | 6 | 4 | F♯ (7) |
| 2 (E) | 3 | 2 | G (1) |
| 1 (A) | 4 | 3 | D♭ (♭5) |
G diminished major 7th is played at the 9th fret as 11 10 9 10: pinky finger on the G string at fret 11, middle finger on the C string at fret 10, index finger on the E string at fret 9 and ring finger on the A string at fret 10.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (G) | 11 | 4 | F♯ (7) |
| 3 (C) | 10 | 2 | B♭ (♭3) |
| 2 (E) | 9 | 1 | D♭ (♭5) |
| 1 (A) | 10 | 3 | G (1) |
G diminished major 7th is played in open position as 0 6 6 4: middle finger on the C string at fret 6, ring finger on the E string at fret 6 and index finger on the A string at fret 4. The G string rings open.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (G) | open | — | G (1) |
| 3 (C) | 6 | 2 | F♯ (7) |
| 2 (E) | 6 | 3 | B♭ (♭3) |
| 1 (A) | 4 | 1 | D♭ (♭5) |
G diminished major 7th is written G°M7 or GdimM7. It is also called augmented minor seventh or minor seventh sharp five.
G diminished major 7th has a major 7th (F♯), while G minor 7th flat 5th has a minor 7th (F). That one semitone changes the chord's color completely.
G diminished major 7th contains a tritone between G and D♭ and a major 7th between G and F♯. Both intervals create strong dissonance that wants to resolve.