For any RealTracks that were released before 2012.5, an "add2" or "add9" chord would not have been recorded. In that case I would suggest these chords because they are usually recorded:

CMaj9 (this will include a 7th)
C9 (this will include a flat 7th)
C2 aka Csus2 (no 7th but will work well if you don't need the 3rd)


And as Mac explained, the octave of the 2nd will depend on the player's style.


Blake

PG Music Inc.