G# m13/D#
The G# m13 chord consists of the G# (Perfect unison), B (Minor third), D# (Perfect fifth), F# (Minor seventh), A# (Major ninth) and F (Major thirteenth) notes, with D# as the bass note.

How to play the G# m13/D# chord
- Play D# as the lowest bass note in the left hand
- Find G# (Root) on the piano keyboard
- Add B (Minor third) — 3 semitones above G#
- Add D# (Perfect fifth) — 7 semitones above G#
- Add F# (Minor seventh) — 10 semitones above G#
- Add A# (Major ninth) — 14 semitones above G#
- Add F (Major thirteenth) — 21 semitones above G#
- Press all 7 notes simultaneously to sound the G# m13/D# chord