ABSTRACT
This chapter investigates two- and four-bar jazz progressions. It also focuses on aural identification and keyboard realization of non-modulatory and modulatory phrases. The ii–V7–I progression constitutes the perfect vehicle to introduce one of the most important features of jazz harmony: the tritone substitution, notated as tritone substitutions (TR/X). Probably the most recognizable progression is a turnaround, also known as a turnback. The turnaround is a two- or four-bar progression, usually with a faster harmonic rhythm that typically occurs at the end of 8- or 16-bar phrases. Jazz musicians often use different harmonic substitutions to modify the content of diatonic progressions. The terms turnaround and tag ending are generic labels that do not indicate a particular chord sequence; rather, they suggest the specific formal function of these progressions. In jazz, there is a certain subset of harmonic progressions whose names suggest specific chord successions. The Giant Steps progression is closely related to the Countdown progression with one exception.
