About the G flat major thirteen chord
The G flat major thirteen chord is a G flat major thirteenth built from G flat, B flat, D flat, F, A flat, E flat. It sits outside the plain diatonic set, so it is borrowed to add color and tension.
It is also written F sharp major thirteen , which spells the same notes enharmonically.
In shorthand it is commonly written Gbmaj13.
Positions
(root position)
Notes and intervals
| 1 | G flat | Root |
| 2 | B flat | Major 3rd |
| 3 | D flat | Perfect 5th |
| 4 | F | Major 7th |
| 5 | A flat | Major 9th |
| 6 | E flat | Major 13th |
Shapes
Chromatic
Circle of Fifths
Other G flat chords
Simpler triads
Suspended
Sixths and sevenths
Extensions
Altered
Functional relationships
These chords are where this one most naturally comes from and resolves to inside a key.
Relative minor
The relative minor uses the same notes and key signature, so it works as a calmer, darker home base.
Parallel minor
The parallel minor keeps the same root note but lowers the third, giving the same key a darker, sadder sound.
Dominant
The dominant is a fifth above the root, and it builds tension that pulls strongly back to this chord.
Subdominant
The subdominant is a fourth above the root (a fifth below), and it usually leads on to the dominant or back home.
Tritone substitution
The tritone substitution stands in for this chord's dominant with a dominant seventh a half step above the root, which slides down by a half step to resolve here.
