Usually these chord charts are in the form of tablature, ... 12 thoughts on “ 3D Printed LED Guitar Chord Chart ” BrotherGecko says: January 18, 2015 at 1:34 am ...

In blues ‘dominant’ 7 chords (A7 or D7 for example) are more common than basic major, minor and sus chords. The A7, D7 and E9 shapes shown here are all you need for a 12-bar blues improv in the key of ...