A Cadence is a 2-Chord formula that marks the end of every Phrase of Classical Music or a Turnaround in Jazz/Pop/Rock/Blues, which is often a point where the music seems to pause, hesitate or stop.   The interruption in the music's flow may result from the shape of the melodic line or more commonly, from a particular sequence of chords associated with the melody.

Some writers describe a cadence as a point when the underlying tension in a moving line of music relaxes but this is quite simplistic as sometimes a cadence can derive its 'effect' from relaxation postponed.

The 3 most common types of Cadences are Perfect, Plagal and Imperfect.   The lowest note in the Cadence chords must be the Root of each chord while the chord notes on top can be an inversion or voicing.

The Perfect Cadence is the most common with the Chord movement always from the V chord to the I chord.

The Plagal Cadence is the next common with the Chord movement always from the IV chord to the I chord.

The Imperfect Cadence has various Chord movements landing on the V chord from the II, III, IV or VI chord.   The IV - V progression is the most common.


  V - I
  IV - I
  IV - V,   II - V,   III - V,   VI - V