B Flat Diminished 7th (also written A#dim7)
Bbdim7 is made of 4 notes: Bb, Db, Fb (E) and Abb (G). Here it is in root position, with Bb at the bottom.
Inside Notley Piano: all the inversions of Bbdim7, fingering for both hands, a play button, and practice that helps you remember it.
| Note | Degree | Interval from Bb |
|---|---|---|
| Bb | 1 | root |
| Db | b3 | minor 3rd |
| Fb (E) | b5 | diminished 5th |
| Abb (G) | bb7 | diminished 7th |
A diminished 7th chord stacks three minor 3rds. It sounds dramatic and spooky, and every note is the same distance apart, so the same shape repeats every three frets.