Prolongation of Seventh Chords is an inttriguing phenomenon that theoretically ought not to exist. Schenkerian theory is based on the premise that prolongations apply to consonsnces alone, and
the violation of this principle has far-reaching consquences. Yet, dissonances in general and seventh chords in particular are occasionally prolonged in traditional tonal music. This issue
remains among the Thorniest in all theoretical discourse on tonal music-- and also might have crucial consequences on the application of Schenkerian theory to post-tonal music. While individual
cases have long been noted, this offers for the first time a systematic survey of the entire spectrum of contrapuntal-harmonic configurations that enable the prolongation of seven chords,
arranged logically by seventh-cord type and voice-leading procedure. Rather thanbeing unique exception, prolongations of certain seventh-cord--especially dominant or diminished
seventh-cord--prove to be common procedure. The analyses are presented in two-volume tradition of Free Composition by Heinrich Schenker and Structural Hearing by Felix Salzer.
