Cadence

Cadence is the term describing the feeling of satisfaction or resolution created by the last of two or more chords in a progression. The two principle cadences in traditional diatonic harmony are the Plagel and Authentic cadences. The Authentic or Dominant Cadence in particular is expanded through the functions of Secondary and Extended Dominants. Other cadential concepts include Modal Cadence and cadence of melody, rhythm and form.

Diatonic Cadence
Plagel (Amen) [sub-dominant]		Authentic [dominant]
IV I F C		V^7--> I G^7--> C
Functional Voice Leading
IV to I: similar motion		V⁷ to I: contrary motion
LA scale-degree 6	>---v		DO scale-degree 1 ( 8 )
	SOL scale-degree 5	TI scale-degree 7	>---^

FA scale-degree 4	>---v	FA scale-degree 4	>---v
	MI scale-degree 3		MI scale-degree 3
IV to I: common tone		V⁷ to I: cycle of fifths [root motion]
		SOL scale-degree 5	>---v
DO scale-degree 1 ( 8 )	DO scale-degree 1 ( 8 )		DO scale-degree 1 ( 8 )

A more general meaning of cadence is a chord sequence, generally consisting of three or more chords. The feeling of completion accompanying the structural (theoretical) resolution identifies the idea of cadence. This can occur in many ways.

examples
Classic Primary Diatonic Cadence	Jazz Sub-Dominant - Dominant - Tonic Cadence
I IV V⁷ I C F G⁷ C	IIm⁷ V⁷ I Dm⁷ G⁷ C