The 12 bar previously introduced in this book is the basis of many different music styles ranging from Blues, Rock, R&B, Soul, Gospel, Country, Funk, Jazz etc.. There are many variations in rhythm, tempo, feel and chord changes. The following example outlines the 12 bar in a common jazz blues version.
Note that all the chords are Dominant Seventh, except in 9th bar.
Example 134 uses chord notes, scale tone notes and chromatic notes.