C mixolydian chordson the mandolin
Main chords: C (I), B♭ (♭VII), F (IV)
The scale: C D E F G A B♭
Drones: Open G and E ring in C mixolydian; D and A fit the key too. The courses are G D A E, low to high.
Common progressions
- I – ♭VII – I: C – B♭ – C
- I – IV – I – ♭VII: C – F – C – B♭ (reels in D or A mix)
- I – ♭VII – IV – I: C – B♭ – F – C (down and back home)
Basis: DADGAD Guitar blog (2009) and common session practice: the flat 7th's major chord (C in D mix) answers the tonic.