C#m7(b5)13 Half-Diminished
The C#m7(b5)13 chord is built from the notes C# – E – G – B – A#.
Piano sound loads on first tap.
Also known as
C#m7b5#13C#m7b5(add13)
Chord tones, one by one
C#Root
Root
The fundamental note the chord is built on — C#.
EThird
Minor third
Three semitones — makes the chord minor (darker, sadder).
GFifth
Diminished fifth (♭5)
Six semitones — a flat fifth. Creates instability, typical of m7♭5 and diminished chords.
BSeventh
Minor seventh (♭7)
Ten semitones — the dominant/minor seventh. Adds bluesy tension (7, m7).
A#Extension
Thirteenth (13)
A 13th — full, rich top extension.
🎼 Related scales
Dorian ♯4 (Ukrainian)harmonic minor a perfect 4th below
🎹 Modal analysis
This chord implies the Dorian ♯4 (Ukrainian) scale; its characteristic note is the ♯4 / ♯11 (the Ukrainian color). It is a mode of the harmonic minor a perfect 4th below.
🎸 Genres
Gypsy jazz · Roma music · Klezmer · Classical