Depending on the size of the xylophone, a diatonic model would consist of the C-major scale: C, D, E, F, G, A, B, C. A chromatic xylophone has the same notes as the black keys on a keyboard: C#, D#, F#, G#, A#, C#, D#. A lot of models have the notes etched onto the corresponding bar to help aid learning and beginners.