Watch the Section 2 online guitar lesson by Robbie Calvo from The Modal Alchemist
In this section of the course I'm going to show you how to use diatonic chord substitutions to improvise over the substituted chord using the chord arpeggios. We'll be working in the key of A for all of these examples to keep the concept clear and concise.
Here are the chord substitutions that you should memorize; The I - III - VI chords and their arpeggios can substitute for each other, the II - IV chords can sub for each other and the V - VII.
The reason we can substitute the chords in this way is that the chord and its sub chord contain 3 common tones of the 4 notes that make up each chord. For example a G major 7 chord contains the notes G - B - D - F#. If we sub the III chord for the I, we get the notes of B minor 7, B - D - F# - A. You can see then that the two chords have 3 common tones.
Work through the next section, taking time to assimilate the information and the concept fully. There is no rush here, take your time and make music.