Watch the Representational online guitar lesson by Christopher Woitach from Jazz Textures
The first section of Jazz Textures is about Representational Harmony. This concept is a more generalized way of looking at chords. Instead of thinking about specific voicings, we'll learn about ways to represent chords, which will give you a much wider chordal palette to draw from. When we're improvising, we need to be flexible, harmonically. Using representations of chords allows us freedom to make chord choices that can fit in with our improvisations any way we wish.
I'll show you some basic substitution concepts, and how that might relate to a typical jazz chart. You'll get a taste of how many chord choices there are, and some ways to make them.