The G♭ Add 9 chord is a four-note chord made up of G♭, B♭, D♭, and A♭. It is built from a root, major third, perfect fifth, and major ninth.
Construction
G♭ Add 9 = Root + Major 3rd + Perfect 5th + Major 2nd = G♭ · B♭ · D♭ · A♭
| Note | Interval | Degree |
|---|---|---|
| G♭ | Root | 1 |
| B♭ | Major 3rd | 3 |
| D♭ | Perfect 5th | 5 |
| A♭ | Major 2nd | 2 |
G♭ Add 9 Inversions
| Position | Notes |
|---|---|
| Root Position | G♭ – B♭ – D♭ – A♭ |
| 1st Inversion | B♭ – D♭ – G♭ – A♭ |
| 2nd Inversion | D♭ – G♭ – A♭ – B♭ |
| 3rd Inversion | G♭ – A♭ – B♭ – D♭ |
Key Signature
A chord has no key signature of its own, but the G♭ Add 9 is the tonic (I) chord of Gb Major, whose key signature has 6 flats (B♭, E♭, A♭, D♭, G♭, C♭).
B♭E♭A♭D♭G♭C♭
Order of flats
Flats are added in a fixed order — the reverse of the sharp order. Each new flat key adds the next flat on the list.
B♭E♭A♭D♭G♭C♭F♭
Mnemonic: Battle Ends And Down Goes Charles’ Father
Chords in the Key of G♭ Major
These are the triads built on each degree of the G♭ major scale:
Same Notes, Other Names
The notes G♭ – B♭ – D♭ – A♭ aren’t exclusive to this chord. Depending on which note is the bass and how the chord functions, the same pitches also spell:
G♭ Add 9 — Frequently Asked Questions
What is the G♭ Add 9 chord on piano?
The G♭ Add 9 chord contains the notes G♭ – B♭ – D♭ – A♭. On piano, play these notes together to sound the chord.
What notes are in the Gb Add 9 chord?
The Gb Add 9 chord (Gbadd9) contains four notes: Gb (root), Bb (major third), Db (perfect fifth), and Ab (major ninth). No seventh — the ninth adds shimmer to the triad.
How does Gbadd9 differ from Gb9?
Gbadd9 has no seventh. Gb9 includes the minor seventh (Fb/E). Gbadd9 is bright; Gb9 is dominant.
How is Gbadd9 used in music?
Gbadd9 substitutes for Gb Major for added colour. Its enharmonic equivalent F#add9 is more commonly written in sharp-key contexts.
What songs use add9 chords?
Add9 chords appear in Wonderwall (Oasis), Good Riddance (Green Day), and countless pop songs. Whether Gbadd9 or F#add9, the sound is identical.
How does Gbadd9 differ from Gbsus2?
Both contain Gb and Ab. Gbadd9 keeps Bb (major third); Gbsus2 replaces it. Gbadd9 is major with colour; Gbsus2 is ambiguous.
Can I substitute Gbadd9 for Gb Major?
Yes — Gbadd9 replaces Gb Major for added shimmer in most contexts.