Space plays and stops
- Notes and intervals
- Bm3Dm3Fm3Ab
B Diminished 7, written Bdim7, is built from B, D, F and Ab: the root, minor 3rd, flat 5th and diminished 7th.
Its 3rd and 7th, D 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, Bdim7 is the ♯i°7 of the Diminished Passing Turnaround in Bb and the ♯iv°7 of the Jazz Blues in F.