Package leaflet · Information for the musician · Chord

C sharp Seventh Sharp Nine Chord (C♯7♯9)

Gritty, funky and aggressive. The sharp ninth rubs against the major third, combining major and minor colours in one chord.

C♯7♯9
5 notes
x43400

1Composition: what it contains

C♯ – E♯ – G♯ – B – D𝄪

Symbol: C♯7♯9
Also written: C♯7♯9, C♯7(♯9), C♯7+9
Formula: 1 3 5 ♭7 ♯9
Same sound as: D♭7♯9

Degree	Note	Interval	Semitones
1	C♯	unison	0
3	E♯	major third	4
5	G♯	perfect fifth	7
♭7	B	minor seventh	10
♯9	D𝄪	augmented ninth	15

2Appearance: diagrams and sound

On the guitar

C sharp Seventh Sharp Nine Chord (C♯7♯9) – guitar chord diagram 1 (x43400) — `x43400`open position

C sharp Seventh Sharp Nine Chord (C♯7♯9) – guitar chord diagram 2 (x4345x) — `x4345x`fret 3

C sharp Seventh Sharp Nine Chord (C♯7♯9) – guitar chord diagram 3 (976667) — `976667`fret 6

C sharp Seventh Sharp Nine Chord (C♯7♯9) – guitar chord diagram 4 (9-11-9-10-9-12) — `9-11-9-10-9-12`fret 9

On the ukulele

C sharp Seventh Sharp Nine Chord (C♯7♯9) – ukulele chord diagram 1 (4414) — `4414`fret 1

C sharp Seventh Sharp Nine Chord (C♯7♯9) – ukulele chord diagram 2 (6577) — `6577`fret 5

C sharp Seventh Sharp Nine Chord (C♯7♯9) – ukulele chord diagram 3 (9-11-9-8) — `9-11-9-8`fret 8

On the piano

Piano keyboard

On the staff

Treble clef

On bass and as an arpeggio

Chord tones on the bass neck

Bass pattern: root and fifth

Bass arpeggio

Chord tones on the guitar neck (degrees)

3Indications: what it is used for

Famous in rock, funk, blues-rock and soul as a tonic dominant chord with attitude, and in jazz as an altered V7 resolving to I or i. Its sharp ninth is enharmonic to the minor third, so it suits minor-pentatonic soloing over a dominant groove. In jazz, the altered scale or half-whole diminished scale fits over it. It frequently appears in blues and funk vamps and as the V chord in minor ii–V–i progressions.

4Dosage: how to practise it

On guitar, learn the classic shape rooted on the fifth string (root, 3, ♭7, ♯9) and practise funk rhythms at 90–120 BPM, muting between hits. On piano, play the left-hand voicing 3-♭7-♯9 and the right-hand altered voicings. Practise iiø7–V7♯9–im and a twelve-bar blues with every chord as 7♯9. Arpeggiate the chord. Five to ten minutes daily. On piano, practise comping with short, accented hits. Try improvising with the blues scale over a 7♯9 vamp, then with the altered scale, to hear both colours.

5Warnings and common mistakes

The sharp ninth is not a minor third: it sits above the major third, which must also be present. Do not confuse 7♯9 with m7, which has no major third. Avoid placing the ♯9 below the third in voicings, which turns the sound into a muddy minor chord. In a major ii–V–I, the sharp ninth may clash with a melody containing the natural ninth. The symbol '7+9' is ambiguous; prefer 7♯9.

6Interactions with chords, scales and keys

Inversions

Inversion 1 · C♯7♯9/E♯ · E♯ – G♯ – B – D𝄪 – C♯
Inversion 2 · C♯7♯9/G♯ · G♯ – B – D𝄪 – C♯ – E♯
Inversion 3 · C♯7♯9/B · B – D𝄪 – C♯ – E♯ – G♯
Inversion 4 · C♯7♯9/D𝄪 · D𝄪 – C♯ – E♯ – G♯ – B

Scales to play over C♯7♯9

C sharp Half-Whole Diminished Scale

7Other presentations available

The same chord from every note

C7♯9 D7♯9 E♭7♯9 E7♯9 F7♯9 F♯7♯9 G7♯9 A♭7♯9 A7♯9 B♭7♯9 B7♯9

Other chords on C♯

C♯ C♯m C♯dim C♯aug C♯sus2 C♯sus4 C♯5 C♯6 C♯m6 C♯7 C♯maj7 C♯m7 C♯m7♭5 C♯dim7 C♯m(maj7) C♯7sus4 C♯add9 C♯m(add9) C♯6/9 C♯9 C♯maj9 C♯m9 C♯11 C♯m11 C♯13 C♯7♭9 C♯7♯5 C♯7♭5

Read this leaflet carefully before playing. Keep it near your instrument. Free to use, print and share for personal and educational use.