C add11
The C add11 chord consists of the C (Perfect unison), E (Major third), G (Perfect fifth) and F (Perfect eleventh) notes.

How to play the C add11 chord
- Find C (Root) on the piano keyboard
- Add E (Major third) — 4 semitones above C
- Add G (Perfect fifth) — 7 semitones above C
- Add F (Perfect eleventh) — 17 semitones above C
- Press all 4 notes simultaneously to sound the C add11 chord