WebeleonThe turnaround is a four-chord loop that walks away from home and straight back: I–vi–ii–V. In C, jazz players voice it
Cmaj7–A7– Dm7–G7, and then they loop it again, because that is the point — a turnaround exists to fill the gap between phrases with motion that always points home. Gershwin built "I Got Rhythm" on it, bebop rebuilt the song into dozens of new standards on the same chassis, and the resulting form — rhythm changes — is, after the 12-bar blues, the most-played harmonic framework in jazz.
Why the vi turns dominant
In the key of C the sixth chord is A minor. Diatonic harmony would give you
Am7, and pop songs voice the loop that way. Jazz sharpens it to A7, and the reason is a chain reaction. A7 is the dominant of D — it is V of ii — so now the whole loop becomes one continuous resolution machine:
- A7 resolves down a fifth to Dm7
- G7 resolves down a fifth to Cmaj7
- and Cmaj7, after a beat of rest, slides to A7 to start the wheel again
One chord quality — that C♯ in the A7 — is what turns four unrelated chords into a single falling-fifths sentence. This is the same engine as the ii–V–I, extended by one link and pointed at itself. If the ii–V–I is a period at the end of a phrase, the turnaround is a conveyor belt that carries you to the period over and over.
The root motion of a I-vi-ii-V in C: C moves down to A, then D and G fall by fifths.
Rhythm changes, the full chassis
"I Got Rhythm" is in B♭, and its A section is the turnaround wearing a melody: B♭maj7–G7–Cm7–F7, repeated until it feels inevitable. The bridge is the famous part — four dominant seventh chords, each lasting two bars, each resolving down a fourth into the next: D7–
G7–C7– F7– back to B♭. Four dominants in a row is the loudest, most directional sound in tonal music, which is why the bridge feels like the shout section even at ballad tempo.
The form — A A B A — plus that harmonic chassis became a public utility. Charlie Parker and Dizzy Gillespie wrote "Anthropology" on it; Sonny Rollins wrote "Oleo" on it; Duke Ellington wrote "Cotton Tail" on it. Different melodies, different eras, same underlying grid. Learn to hear the grid once and all of these tunes arrive pre-learned.
One honest caveat: "rhythm changes" names the framework, not one progression. Every bebop head reharmed the A section — extra ii–Vs, diminished passes, substitutions — so two songs on the chassis can share almost no chords in common measure by measure. The grid is the starting position, not the rule.
The Tadd Dameron turnaround
In the late 1940s, arranger Tadd Dameron found the slickest edit the loop admits. Take I–VI7–II7–V7 and replace the VI7 and II7 with their tritone substitutions — A7 becomes E♭7, D7 becomes A♭7 — and the loop becomes
Cmaj7–E♭7– A♭7–D♭7. Every substitution resolves exactly where the chord it replaced resolved, because a dominant seventh and its tritone twin share the same tritone — the engine of the resolution — swapped between voices.
What changes is the bass line, and it is a beautiful line: C up to E♭, then fourths down through A♭ to D♭, then a half step up into C. Smooth where the original was angular. When you hear a turnaround glide in a Wayne Shorter or McCoy Tyner arrangement where the original would clunk, this substitution is usually why.
Hearing it, then keeping it
Ear-training path: play the plain loop, Cmaj7–
A7–Dm7– G7, and sing the roots. Then swap in the Tadd Dameron version and sing again — the resolutions land in the same places, which is the sound of a substitution done right. If a swap ever makes the next chord sound less expected rather than more, the substitution was wrong for the spot; not every turnaround wants the smooth bass.
The fastest setup for both loops is a sketch in Homechord: four chords, loop on, swap A7 for E♭7 with one edit and hear thirty years of jazz harmony arranging itself. Then try the rhythm changes bridge in B♭ and feel how four dominants in a row pull a whole form back home.