Space plays and stops
- Notes and intervals
- Bbm3Dbm3FbM3Ab
Bb Half Diminished, written Bbm7b5, is built from Bb, Db, Fb and Ab: the root, minor 3rd, flat 5th and minor 7th.
Its 3rd and 7th, Db and Ab, are its guide tones: they say what kind of chord it is, so voicings are built around them and the root is often left to the bass.
In the progressions here, Bbm7b5 is the iiø7 of the Minor ii-V Progression in Ab, the viø7 of the Minor i-vi-ii-V Progression in Db and the iiiø7 of the Minor ii-V to ii-V-I Progression in Gb.