Construction
B Diminished Major 7th = Root + Minor 3rd + Diminished 5th + Major 7th = B, D, F, A♯
| Note | Interval | Degree |
|---|---|---|
| B | Root | 1 |
| D | Minor 3rd | ♭3 |
| F | Diminished 5th | ♭5 |
| A♯ | Major 7th | 7 |
Fingering
| Note | Key color | Right hand | Left hand |
|---|---|---|---|
| B | white | thumb (1) | little finger (5) |
| D | white | index finger (2) | middle finger (3) |
| F | white | middle finger (3) | index finger (2) |
| A♯ | black | little finger (5) | thumb (1) |
Right hand: thumb (1) on B, index finger (2) on D, middle finger (3) on F, little finger (5) on A♯.
Left hand: little finger (5) on B, middle finger (3) on D, index finger (2) on F, thumb (1) on A♯.
Key Signature
A Diminished Major 7th chord is built from symmetrical or ambiguous intervals, so it doesn't belong to a single key and has no key signature of its own.
Chords in the Key of B Major
These are the triads built on each degree of B Major:
B Diminished Major 7th : Frequently Asked Questions
What is the B Diminished Major 7th chord on piano?
The B Diminished Major 7th chord contains the notes B – D – F – A♯. On piano, play these notes together to sound the chord.