Basic Chord Substitutions
Whenever you play a different harmony than the one originally intended or written, you are playing a chord substitution. Jazz musicians regularly use substitutions to add variety and interest to the sound. The most basic chord substitutions replace the existing chord with a closely related chord. For example in the key of C instead of playing a C major chord (I), you play an A minor chord (vi) or an E minor chord (iii). Thinking back on the baseball diamond analogy, each base had two closely related chords associated with it. You can usually substitute the ii chord for the IV chord since they are closely related. Likewise, the V and vii0 chords can be used interchangeably.
Figure 18-6 uses very basic chord substitutions for “Amazing Grace” to demonstrate the concept of playing a closely related chord instead of the one originally written. The first time through, the original chords are played; and the second time through, the substitutions are added.
FIGURE 18-6: “Amazing Grace” chord substitutions
Chord substitutions add interest and variety to your playing, and are an expansion of your playing by ear technique. You can add creativity to your playing by using closely related chords at the appropriate times.
Are closely related chords the only substitutions allowed?
Of course not! Closely related chords are the easiest substitutions to understand and play. The universe of chord substitutions is enormous, and can be as simple or as complex as your abilities and artistic desires dictate. This chapter serves only as a basic introduction to chord substitutions.