RHYTHM CHANGES - DEFINITION

Rhythm Changes is the second main form used in jazz, next to the 12 bar blues. The term "Rhythm Changes" is derived from the chord sequence of George Gershwin's 'I Got Rhythm' which has 32 bars (missing out the coda) comprising:

 · A1     8 bars finishing on an imperfect cadence
 · A2     a repeat of the first 8 bars finishing on a perfect cadence
 · B       the "middle eight" or "bridge section" which is in a related key, leading back to…
 · A3     a repeat of the first 8 bars, finishing with a perfect cadence

The complete form can be summarised as AABA and tunes which use this form are therefore known as "rhythm changes" tunes.