A#dim A# diminished chord
- Notes
- A# C# E
- Formula
- 1 b3 b5
- Semitones
- 0 3 6 above the root
- Also written
- Bbdim (Bb Db Fb)
- Other symbols
- A#°, A#m(b5)
A# to C# is a minor third (3 semitones), C# to E is a minor third (3 semitones). Two minor thirds stacked, so A# to E is a tritone (6 semitones) instead of a perfect fifth. The four-note A#dim7 and A#m7b5 grow from it by adding a note on top.
A#dim on the piano
Root position from A#4: A#4, C#5, E5. Middle C is C4.
A#dim on the guitar
Standard tuning (E A D G B E). Strings run low E on the left to high e on the right, frets downwards; × is a muted string, ○ an open string, and each dot shows the note it sounds, with the root in blue-green. Every shape below has A# as its lowest note.
x 1 2 3 2 x (low E to high e)
Sounds A#2 E3 A#3 C#4
6 7 8 6 x x (low E to high e)
Sounds A#2 E3 A#3 C#4
The barre shapes are movable: an E-shape chord's root is the note under your first finger on the low E string, an A-shape chord's root is the note on the A string. Slide the same grip up or down to play diminished chords on other roots.
Inversions of A#dim
An inversion puts a note other than the root in the bass. The name is what semicord's chord finder calls those notes played bottom to top; a slash name like C/E means a C chord with E in the bass.
| Position | Notes, bass first | Named | Listen |
|---|---|---|---|
| Root position | A# C# E | A#dim | |
| 1st inversion | C# E A# | A#dim/C# | |
| 2nd inversion | E A# C# | A#dim/E |
Where A#dim fits
A#dim is vii° in B major, ii° in G# minor, vii° in B minor. Its root A# is the leading tone of B: a half step below the tonic, so the chord usually moves up to it.