Dominant 7th #5 #9
7#5#9
0 - 4 - 8 - 10 - 15Dom7 with augmented 5th and 9th
About Dominant 7th #5 #9
A dominant seventh sharp five sharp nine chord alters two degrees upward at once — in C that is C, E, G♯, B♭ and D♯, written C7♯5♯9. It is the brightest of the altered dominants, and the one bebop turnarounds reach for when a resolution needs to arrive with force rather than with menace.
Notes and formula
The formula is 1 – 3 – ♯5 – ♭7 – ♯9, or 0 – 4 – 8 – 10 – 15 in semitones. Both alterations raise a degree, which is what separates this chord from its flat-nine relative.
The raised fifth and the raised ninth are five semitones apart, so the chord holds no cluster. It is dense but not muddy, which is why it survives being played by a whole section.
How to play it
On guitar the movable form is x–3–x–3–4–4, sounding C–B♭–D♯–G♯: root, seventh and both alterations, with the third left to whoever else is playing.
On piano the standard voicing is C low, then E–G♯–D♯ above. The B♭ can go if the bass is covering the harmony — of the two chord-defining notes, the third is the one that must stay when alterations crowd the voicing.
What it does
A 7♯5♯9 chord resolves down a fifth like every dominant, and it does so with unusual force. Both alterations sit a semitone below notes of the destination chord, so the resolution moves two voices by step in the same direction.
That is the technical reason it sounds emphatic rather than merely tense, and it is why arrangers place it in the last bar before a final tonic.
Against its mirror
C7♯5♭9 alters one degree up and one down. C7♯5♯9 raises both. The difference is a single semitone in the ninth, and the chords sound noticeably different: raised ninths are bluesy, lowered ninths are dramatic.
In a chart the two are one character apart, and playing the wrong one changes the colour of the bar without making it wrong.
Where you hear it
Bebop and hard bop, at the end of turnarounds. Big-band writing, in the penultimate chord of a shout chorus. Soul and funk horn sections, where the chord is played as a stab rather than held.
It is almost absent from music without a jazz lineage, for the same reason as every heavily altered dominant: the ear has to be trained to hear it as a dominant at all.
Scales that contain it
The altered scale contains both alterations and is the standard choice. The whole-tone scale contains the raised fifth but not the raised ninth, so it fits only partly.
Where the chord is played as a stab rather than held, players often outline the chord tones instead of running a scale — with four notes this specific, the arpeggio is more characteristic than any scale.
Frequently asked questions
What notes are in a C7♯5♯9 chord?
C, E, G♯, B♭ and D♯. On guitar, x–3–x–3–4–4.
How is it different from 7♯5♭9?
One semitone in the ninth. The raised ninth is the blues clash between a major and a minor third; the lowered ninth is the diminished sound of a classical cadence.
Can I leave notes out?
Yes — the fifth is already altered, and the seventh can go if the bass is clear. The third and at least one alteration are what identify the chord.