Rule of thirds...for chord construction. 1 3 5 7 9 11 13 C e g b d f a - Cmaj13 Easy to explain to a beginner. C e g b db f a - Cmaj13b9 C db g b d f a - con

Rule of thirds...for chord construction. 1 3 5 7 9 11 13 C e g b d f a - Cmaj13 Easy to explain to a beginner. C e g b db f a - Cmaj13b9 C db g b d f a - confusion (for beginners) as that would not have a third....'d' is the 2nd letter alphabetically. Any key sig can be represented... Ie 'E' has to be followed by a g 'of some kind', so even e# can be followed by a gb g or g# to construct a chord. Easy to see on a guitar, especialky with multiple positions to sound the same note. e g b d f a c e g b d f a c e....rotates forever, whatever the starting note.