Minor 9th
Bbm9 is a minor seventh chord rooted on Bb. It has a dark, mellow, and introspective quality that forms the backbone of minor key harmony in jazz. Minor seventh chords most commonly function as the ii chord in a ii-V-I progression (Levine, The Jazz Theory Book).
19 voicings · minor
Left Hand
Right Hand
Left Hand
Right Hand
Left Hand
Right Hand
Left Hand
Right Hand
Left Hand
Right Hand
Left Hand
Right Hand
Melody (C6) doubled an octave below (Bb4) with chord tones in between
Left hand alternates between bass note and chord
Beat 1 & 3 — Bb3
Beat 2 & 4 — C, Db, Ab
Left hand alternates between bass note and chord
Beat 1 & 3 — F3
Beat 2 & 4 — C, Db, Ab
The minor seventh chord functions as the ii chord in major keys, the i chord in minor keys, or the iii and vi chords in various contexts (Mulholland & Hojnacki, The Berklee Book of Jazz Harmony). As the ii chord, Bbm9 is the gateway to the V-I resolution — the most common harmonic progression in jazz. Mantooth emphasises practising ii-V-I voicings in all 12 keys as the foundation of jazz keyboard fluency (Voicings for Jazz Keyboard).
Commonly paired with the Dorian mode when functioning as ii — the natural sixth gives it a brighter quality than Aeolian (Aebersold, Jazz Handbook). As a i chord in minor keys, Dorian is also standard, though Aeolian and melodic minor are used depending on context.
Minor seventh chords typically resolve down a fifth to a dominant seventh chord. Bbm9 commonly moves to a V7 chord a fourth above (Levine, The Jazz Theory Book).
ii-V-I
Bbm9 as the ii chord, resolving through V7 to Imaj7
Minor ii-V-i
Bbm9 (or Bbm7b5) as ii, to V7b9, to im7
Modal vamp
Bbm9 held as a modal centre in Dorian mode
Bbm9 is a four-note chord containing Bb, minor third, perfect fifth, and minor seventh. It creates a warm, dark sound essential to jazz harmony. In Roman numeral analysis, it most often appears as ii (Mulholland & Hojnacki, The Berklee Book of Jazz Harmony).
Common voicings include shell (root, b3, b7), rootless Type A (b3, 5, b7, 9), and rootless Type B (b7, 9, b3, 5). Levine calls these "left-hand voicings" and recommends learning them through the cycle of fifths in all 12 keys (The Jazz Piano Book).
Bbm is a minor triad (three notes). Bbm9 adds the minor seventh, creating a four-note chord with a jazzier, more sophisticated sound. In jazz, Bbm9 is almost always preferred over Bbm.
The ii-V-I progression is the most common chord progression in jazz. Learning to voice the ii chord smoothly is the first step in jazz piano fluency.
— Mantooth, Voicings for Jazz Keyboard, Ch. 1
Minor seventh chords pair with the Dorian mode. The raised sixth degree distinguishes Dorian from Aeolian and gives the minor chord a brighter quality.
— Aebersold, Jazz Handbook