Originally Posted by
Nevin
Arpeggios are just playing the notes of a chord individually, one after another. From a theory prospective the basic chord (called a triad) are based on scales. Chords are made from every other note from the starting note (the root, 3rd, and 5th notes in the case of a triad). In your instance where you are playing C, D, and G arpeggios, You are playing in G Major. The notes in a G Major scale are G, A, B, C, D, E, F#. So a triad made starting on G has the notes G, B, and D. Starting on C you get C, E, and G. Starting on D you get D, F#, and A. These are all major triads. One source of confusion to beginners is that the order of the notes doesn't change the name. For instance the simplest C Major chord on a mandolin (using open strings) Is voiced G, E, C, E. It is still a C major triad.