D7b9 D dominant seventh flat nine chord
- Notes
- D F# A C Eb
- Formula
- 1 3 5 b7 b9
- Semitones
- 0 4 7 10 13 above the root
- Other symbols
- D7(b9), D7-9
D to F# is a major third (4 semitones), F# to A is a minor third (3 semitones), A to C is a minor third (3 semitones), C to Eb is a minor third (3 semitones). A dominant seventh with a flattened ninth, Eb, a half step (plus an octave) above the root. It is the sharpest-sounding of the common dominant chords and pulls hard towards a minor tonic.
D7b9 on the piano
Root position from D4: D4, F#4, A4, C5, Eb5. Middle C is C4.
D7b9 on the guitar
Standard tuning (E A D G B E). Strings run low E on the left to high e on the right, frets downwards; × is a muted string, ○ an open string, and each dot shows the note it sounds, with the root in blue-green. Every shape below has D as its lowest note.
x 5 4 5 4 x (low E to high e)
Sounds D3 F#3 C4 Eb4, fifth left out
10 x 10 11 10 11 (low E to high e)
Sounds D3 C4 F#4 A4 Eb5
The E-shape and A-shape grips are movable: an E-shape chord's root is the note under your first finger on the low E string, an A-shape chord's root is the note on the A string. Slide the same grip up or down to play dominant seventh flat nine chords on other roots.
Inversions of D7b9
An inversion puts a note other than the root in the bass. The name is what semicord's chord finder calls those notes played bottom to top; a slash name like C/E means a C chord with E in the bass.
| Position | Notes, bass first | Named | Listen |
|---|---|---|---|
| Root position | D F# A C Eb | D7b9 | |
| 1st inversion | F# A C Eb D | D7b9/F# | |
| 2nd inversion | A C Eb D F# | D7b9/A | |
| 3rd inversion | C Eb D F# A | D7b9/C | |
| 4th inversion | Eb D F# A C | D7/Eb (also read as D7b9/Eb) |
Where D7b9 fits
D7b9 is V7b9 in G minor. Its upper four notes F# A C Eb are F#dim7, so D7b9 and that diminished seventh are interchangeable over a D bass. The flat ninth Eb falls a half step to the fifth of Gm.