C add chords
C add chords for piano with keyboard diagram.
Explanation: The Cadd9 and Cadd2 are four note chords. Cadd2 is sometimes written as C2.
Theory: Both chords contain the same notes, but the added notes belong to different octaves which are the ninth and the second notes in the scale.
Notes: C - E - G - D
Notes: C - D - E - G