"Good improvisation communicates harmonic progression melodically. Effective melodies manipulate harmonic content through the use of guide tones and preparatory gravity notes, masterfully woven in systematic tension, release, and transparent harmonic definition."
We could argue that nobody explains jazz theory better than pedagogy expert Dan Haerle. He's mentored many a student in his years with Aebersold Summer Jazz Workshops, penned a half dozen of the most important method books out there, and was a major influence in jazz education as a faculty member of the University of North Texas until retiring from full time teaching in 2002.
We've brought up the subject of "Guide Tones" in some of our own Mel Bay materials (Guides and Gravity) and the Axis of the 3rds and 7ths, but Professor Haerle does a terrific job in demonstrating them in the video below. Nothing beats hearing the concept of the way linear is expressed in the complex vertical nature of jazz.
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