F add9 Chord
How the F add9 chord is built: its notes, its interval structure, and where it fits.
The F add9 chord contains 4 notes: F – G – A – C. It belongs to the ninth & extended family of chord qualities. Like every chord, it is defined by the distances (intervals) between its notes, not by any one instrument — which is why the same formula names the chord whether it is voiced on a fretboard, a keyboard, or a choir.