C7♯5

C Dominant 7th Sharp 5 — the augmented dominant — the raised fifth leans hard into the resolution a fifth below.

The keys
C4C5C6
C – E – G♯ – B♭
What's inside C7♯5
NoteInterval from rootDegree
CRoot1
EMajor 3rd3
G♯Augmented 5th#5
B♭Minor 7thb7
Inversions
PositionKeys (low → high)
Root positionC4 – E4 – A♭4 – B♭4
1st inversionE4 – A♭4 – B♭4 – C5
2nd inversionA♭4 – B♭4 – C5 – E5
3rd inversionB♭4 – C5 – E5 – A♭5
A working voicing

Split the chord between two hands the way working players do — a solid shell low down, the colour tones up top:

HandKeys
Left (shell)C2 – B♭2
Right (colour)E4 – A♭4
Where C7♯5 lives

Hard resolution

C7♯5 → Fm9

Altered dominants resolve with maximum drama — especially into minor.

Chromatic approach

Gm7 → C7♯5 → F

The alteration sharpens the pull of the standard two-five.

Put C7♯5 under your fingers

Hear every voicing, see the keys light up, and drill it in the interactive Chord & Voicing Lab.

Open the Chord & Voicing Lab →