B-altb13 Half-Diminished
The B-altb13 chord is built from the notes B – D – F – A – C – E#.
Piano sound loads on first tap.
Chord tones, one by one
BRoot
Root
The fundamental note the chord is built on — B.
DThird
Minor third
Three semitones — makes the chord minor (darker, sadder).
FFifth
Diminished fifth (♭5)
Six semitones — a flat fifth. Creates instability, typical of m7♭5 and diminished chords.
ASeventh
Minor seventh (♭7)
Ten semitones — the dominant/minor seventh. Adds bluesy tension (7, m7).
CExtension
Flat ninth (♭9)
A ♭9 — sharp, dissonant tension typical of altered dominant chords.
E#Extension
Sharp eleventh (♯11)
A ♯11 — the bright, floating Lydian color.
🎼 Related scales
🎹 Modal analysis
This chord implies the Locrian scale; its characteristic note is the unstable ♭5.
🎸 Genres
Modern jazz · Post-bop · Fusion