C-alt7b5 Half-Diminished

The C-alt7b5 chord is built from the notes C – Eb – Gb – Bb – Db – D#.

Piano sound loads on first tap.

Chord tones, one by one

CRoot

Root

The fundamental note the chord is built on — C.

EbThird

Minor third

Three semitones — makes the chord minor (darker, sadder).

GbFifth

Diminished fifth (♭5)

Six semitones — a flat fifth. Creates instability, typical of m7♭5 and diminished chords.

BbSeventh

Minor seventh (♭7)

Ten semitones — the dominant/minor seventh. Adds bluesy tension (7, m7).

DbExtension

Flat ninth (♭9)

A ♭9 — sharp, dissonant tension typical of altered dominant chords.

D#Extension

Sharp ninth (♯9)

A ♯9 — the gritty 'Hendrix' tension over a dominant chord.

🎼 Related scales

🎹 Modal analysis

This chord implies the Locrian scale; its characteristic note is the unstable ♭5.

🎸 Genres

Modern jazz · Post-bop · Fusion

-alt7b5 in every key

More C chords

More C chords from Locrian