What Bdim is built from
Counting up in semitones from B:
| Note | Interval | Semitones from root |
|---|---|---|
| B | root | 0 |
| D | minor third | 3 |
| F | diminished fifth | 6 |
Move all three of those the same distance and you get the same chord on another root — that is what the diminished triad formula 0 – 3 – 6 means.
How to play Bdim
Leave the low E and top E strings out. Nothing is higher than fret 4, so it sits in first position.
All four strings are played. Nothing is higher than fret 4, so it sits in first position.
Play B, D and F together. All three are white keys.
Numbers in the grids are frets. Where a number is printed beside a grid, that is the fret the top row stands for; otherwise the thick bar at the top is the nut. A circle above a string means play it open, a cross means leave it out.
Guitar, string by string
| Guitar string | Stopped at | Sounds |
|---|---|---|
| low E | not played | — |
| A | fret 2 | B |
| D | fret 3 | F |
| G | fret 4 | B |
| B | fret 3 | D |
| top E | not played | — |
Ukulele, string by string
| Ukulele string | Stopped at | Sounds |
|---|---|---|
| G | fret 4 | B |
| C | fret 2 | D |
| E | fret 1 | F |
| A | fret 2 | B |
Bdim on the stave
The same three notes written on a treble stave, spelled the way a diminished triad is spelled — one letter for every other step, with whichever accidental reaches the pitch. That is why it reads B, D and F, and not the same sounds written some other way.
Which keys Bdim belongs to
| Key | Relative minor | Degree |
|---|---|---|
| C major | A minor | vii° |
Each row is a key whose scale contains every note of Bdim. A major key and its relative minor use the same seven notes, so the chord belongs to both.
Chords that sit next to Bdim
The seven triads built on the scale of C major. These are the chords Bdim is most often played alongside, because they are made from the same seven notes. The small numeral is the degree each one stands on.
Other chords on B
Same root, different notes above it.
Chords straight off a recording
Upload a track and the studio marks its chords, key and tempo against the beat, with these same shapes and the stave underneath.
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