semicord

Db7#9 Db dominant seventh sharp nine chord

Notes
Db F Ab Cb E
Formula
1 3 5 b7 #9
Semitones
0 4 7 10 15 above the root
Also written
C#7#9 (C# E# G# B D##)
Other symbols
Db7(#9), Db7+9

Db to F is a major third (4 semitones), F to Ab is a minor third (3 semitones), Ab to Cb is a minor third (3 semitones), Cb to E is a perfect fourth (5 semitones). A dominant seventh with a raised ninth, E. On the keyboard E is the same key as the minor third, so the chord holds both a major and a minor third; it is written as a sharp ninth because it sits above the seventh and the letter names follow the stack of thirds.

Db7#9 on the piano

C4D4E4F4G4A4Cb5C5D5E5F5G5A5B5Db4Eb4F#4Ab4Bb4C#5Eb5F#5Ab5Bb5C4DbFAbCbC5E

Root position from Db4: Db4, F4, Ab4, Cb5, E5. Middle C is C4.

Db7#9 on the guitar

Standard tuning (E A D G B E). Strings run low E on the left to high e on the right, frets downwards; × is a muted string, ○ an open string, and each dot shows the note it sounds, with the root in blue-green. Every shape below has Db as its lowest note.

×DbDbFFCbCbEE×
A-shape, root on the A string at fret 4
x 4 3 4 5 x (low E to high e)
Sounds Db3 F3 Cb4 E4, fifth left out

The E-shape and A-shape grips are movable: an E-shape chord's root is the note under your first finger on the low E string, an A-shape chord's root is the note on the A string. Slide the same grip up or down to play dominant seventh sharp nine chords on other roots.

Inversions of Db7#9

An inversion puts a note other than the root in the bass. The name is what semicord's chord finder calls those notes played bottom to top; a slash name like C/E means a C chord with E in the bass.

PositionNotes, bass firstNamedListen
Root positionDb F Ab Cb EDb7#9
1st inversionF Ab Cb E DbC#m7/F (also written Dbm7/F; also read as Db7#9/F)
2nd inversionAb Cb E Db FDb7#9/Ab
3rd inversionCb E Db F AbDb7#9/B
4th inversionE Db F Ab CbC#7/E (also written Db7/E; also read as Db7#9/E)

Where Db7#9 fits

Db7#9 has no place among the chords built from a major or minor scale: it holds a major third, F, and the sharp ninth E, which sounds the same as the minor third. That major–minor clash is the blues in one chord. It is used as the I chord of a blues or a funk vamp, and as a tense V chord in jazz; Jimi Hendrix's "Purple Haze" made E7#9 famous, which is why guitarists call it the Hendrix chord.