B Flat Diminished (also written A#dim)
Bbdim is made of 3 notes: Bb, Db and Fb (E). Here it is in root position, with Bb at the bottom.
Inside Notley Piano: all the inversions of Bbdim, 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 |
A diminished chord stacks two minor 3rds, so it has a flat 5th. It sounds tense and unstable, and is usually used as a passing chord.