Bbaug13 Augmented
The Bbaug13 chord is built from the notes Bb – D – F# – Ab – G.
Piano sound loads on first tap.
Also known as
Chord tones, one by one
Root
The fundamental note the chord is built on — Bb.
Major third
Four semitones — makes the chord major (brighter, happier).
Augmented fifth (♯5)
Eight semitones — a sharp fifth. Restless and dreamy, typical of augmented chords.
Minor seventh (♭7)
Ten semitones — the dominant/minor seventh. Adds bluesy tension (7, m7).
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