there are three chords present on the harp: C major (channel 1,2,3 blow) G major (pull channel 1,2,3) D minor (pull channel 4,5,6 and 8,9,10) With them it is possible to accompany practically all popular music because it is based on these 3 chords. In order to be able to use these chords, you have to play in the 2nd position (cross harp), in this case G major. When playing in the key in which the instrument is tuned - e.g. C major on the C harp - then only two chords are usable: C major and G major. D minor is out of place here. Therefore the accompaniment with the chords to a song can only be realized via the 2nd position. For the C harp this means when playing in G major, the 2nd position: the C major chord is on the 4th degree, the G major chord on the 1st degree and the D minor chord is built on the 5th degree of the G major scale. This chord progression is standard in popular music and therefore also in the blues. The blues scheme is also based on this. We always have these three chords available on every harp - no matter what key it is tuned in. Greetings from Astrid
I hope it helps you.