How do you play the C dim/B chord?

To play the C dim/B chord on piano, play the C dim chord (C, D# and F#) with B as the lowest bass note. Place the B note below the other chord tones. Slash chords specify a particular bass note different from the chord root.

What is a slash chord?

A slash chord (or compound chord) is written as Chord/Bass and specifies both a chord and a bass note. The note to the right of the slash is played as the lowest note. The C dim/B chord means a C dim chord with B in the bass.

C dim/B

Q: What notes are in the C dim/B chord?

The C dim/B chord uses the 3 notes of the C dim chord — C (Perfect unison), D# (Minor third) and F# (Diminished fifth) — with B played as the bass note in the lowest register.

The C dim chord consists of the C (Perfect unison), D# (Minor third) and F# (Diminished fifth) notes, with B as the bass note.

Piano keyboard showing the notes for a C dim/B chord

How to play the C dim/B chord

Play B as the lowest bass note in the left hand
Find C (Root) on the piano keyboard
Add D# (Minor third) — 3 semitones above C
Add F# (Diminished fifth) — 6 semitones above C
Press all 4 notes simultaneously to sound the C dim/B chord

Inversions with same root

B addb9

Related chords with different root

C m(maj7)(b5)