Bbm(maj7b5b9add13) Diminished
The Bbm(maj7b5b9add13) chord is built from the notes Bb – Db – Fb – A – Cb – G.
Piano sound loads on first tap.
Chord tones, one by one
Root
The fundamental note the chord is built on — Bb.
Minor third
Three semitones — makes the chord minor (darker, sadder).
Diminished fifth (♭5)
Six semitones — a flat fifth. Creates instability, typical of m7♭5 and diminished chords.
Major seventh
Eleven semitones — a lush, jazzy seventh just below the octave (maj7).
Flat ninth (♭9)
A ♭9 — sharp, dissonant tension typical of altered dominant chords.
Thirteenth (13)
A 13th — full, rich top extension.
🎹 Modal analysis
This chord is so rich it doesn't fit a single scale: it's a polychord (an “upper structure”) that stacks tensions from several scales at once. It doesn't work like a dominant that “wants” to resolve — it's pure color: picture one triad floating over an unrelated bass, the kind of sound used in reharmonization and modal passages. To make sense of it, follow the note-by-note breakdown above.
🎸 Genres
Modern jazz · Fusion · Film & TV scoring · Impressionism