B add13/D#
The B add13 chord consists of the B (Perfect unison), D# (Major third), F# (Perfect fifth) and G# (Major thirteenth) notes, with D# as the bass note.

How to play the B add13/D# chord
- Play D# as the lowest bass note in the left hand
- Find B (Root) on the piano keyboard
- Add D# (Major third) — 4 semitones above B
- Add F# (Perfect fifth) — 7 semitones above B
- Add G# (Major thirteenth) — 21 semitones above B
- Press all 5 notes simultaneously to sound the B add13/D# chord