Jazz Guitar CHORD EVOLUTION

The colored diagrams shown at the right compare the major triads to their system chord extensions.

Unlike the root or basic chords, which have duplicate notes, the system diagrams consist of 6 different notes, facilitating within each, 15 possible 4 note chords that are accessible as logical substitutes for each other simply by selecting different combinations of 4 notes with right hand fingers. Use additional 3 or 5 note chord options by employing fewer or more right hand fingers as well.

The system diagrams are essentially derived from 13th chords.

CHORD ALTERATION CHART:
These diagrams are useful as chord alteration charts for their corresponding more commonly seen major chord formations. While this chart is not actually a part of the improvisation system offered, it's use as a chord alteration chart for basic guitar chord forms is pretty obvious.

Keep in mind though, for altering basic chords, there are a few chord nomenclatures that may need clarification if you are new at this. There aren't many though so don't let them throw you. Here's a couple of common examples.

1. When a chord symbol calls for a "7", (ie A7) it really means flat 7 (b7) where the 7 that's shown in the diagram would be lowered in pitch by one fret.

2. The note "7" just as it is shown in the diagram would be represented by a chord symbol that looks like the following: "Maj7", or "Mj7", or a third possibility, which unfortunately cannot be made with a keyboard that I can only describe as "the number 7 with a dash through the center of it. (the way many Europeans would make a 7").

3. When a chord symbol is labeled "sus" or "sus4", it means that a 4 substitutes for the 3 in any chord.

4. An "augmented" chord, who's chord symbol would be "A+" or "A+5" or "Aaug" or "Aaug5" is calling for a chord who's 5, as it is represented in the chart, would be raised in pitch by one fret.