The D 9sus4 chord is a five-note chord made up of D, G, A, C, and E. It is built from a root, perfect fourth, perfect fifth, minor seventh, and major ninth.
Construction
D 9sus4 = Root + Perfect 4th + Perfect 5th + Minor 7th + Major 2nd = D · G · A · C · E
| Note | Interval | Degree |
|---|---|---|
| D | Root | 1 |
| G | Perfect 4th | 11 |
| A | Perfect 5th | 5 |
| C | Minor 7th | ♭7 |
| E | Major 2nd | 9 |
Key Signature
A chord has no key signature of its own, but the D 9sus4 is the tonic (I) chord of D Major, whose key signature has 2 sharps (F♯, C♯).
F♯C♯
Order of sharps
Sharps are added to a key signature in a fixed order. Each new sharp key adds the next sharp on the list.
F♯C♯G♯D♯A♯E♯B♯
Mnemonic: Father Charles Goes Down And Ends Battle
Chords in the Key of D Major
These are the triads built on each degree of the D major scale:
Same Notes, Other Names
The notes D – G – A – C – E aren’t exclusive to this chord. Depending on which note is the bass and how the chord functions, the same pitches also spell:
D 9sus4 — Frequently Asked Questions
What is the D 9sus4 chord on piano?
The D 9sus4 chord contains the notes D – G – A – C – E. On piano, play these notes together to sound the chord.
What notes are in the D 9sus4 chord?
The D 9sus4 chord (D9sus4) contains 5 notes: D, G, A, C, E. Formula: R-P4-P5-m7-M9.
How is D9sus4 used in music?
D9sus4 is used in jazz, fusion, and contemporary music to add harmonic color. It appears as a dominant or tonic chord depending on context.
What is the scale degree formula for D9sus4?
D9sus4 uses scale degrees 1-4-5-b7-9, giving it its distinctive sound.