The C♯ 6/9 chord is a five-note chord made up of C♯, E♯, G♯, A♯, and D♯. It is built from a root, major third, perfect fifth, major sixth, and major ninth.
Construction
C♯ 6/9 = Root + Major 3rd + Perfect 5th + Major 6th + Major 2nd = C♯ · E♯ · G♯ · A♯ · D♯
| Note | Interval | Degree |
|---|---|---|
| C♯ | Root | 1 |
| E♯ | Major 3rd | 3 |
| G♯ | Perfect 5th | 5 |
| A♯ | Major 6th | 6 |
| D♯ | Major 2nd | 2 |
Key Signature
A chord has no key signature of its own, but the C♯ 6/9 is the tonic (I) chord of C# Major, whose key signature has 7 sharps (F♯, C♯, G♯, D♯, A♯, E♯, B♯).
F♯C♯G♯D♯A♯E♯B♯
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 C♯ Major
These are the triads built on each degree of the C♯ major scale:
Same Notes, Other Names
The notes C♯ – E♯ – G♯ – A♯ – D♯ aren’t exclusive to this chord. Depending on which note is the bass and how the chord functions, the same pitches also spell:
C♯ 6/9 — Frequently Asked Questions
What is the C♯ 6/9 chord on piano?
The C♯ 6/9 chord contains the notes C♯ – E♯ – G♯ – A♯ – D♯. On piano, play these notes together to sound the chord.
What notes are in the C# 6/9 chord?
The C# 6/9 chord (C#6/9) contains 5 notes: C#, F, G#, A#, D#. Formula: R-M3-P5-M6-M9.
How is C#6/9 used in music?
C#6/9 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 C#6/9?
C#6/9 uses scale degrees 1-3-5-6-9, giving it its distinctive sound.