Quick-change blues and the I–VI–II–V turnaround

Two changes to the twelve bars of step 1: the IV arrives in bar 2, and the last two bars turn around through four chords instead of two. Still a shuffle, still your blues — with the first ii–V of the ladder in it.

Your key

1A7I7

2D7IV7

3A7I7

4A7I7

5D7IV7

6D7IV7

7A7I7

8A7I7

9E7V7

10D7IV7

11A7I7F♯7VI7

12Bm7IIm7E7V7

New in this step

▶ Play it in JamShed

Tempo

Shuffle · 104 bpm · A · the trio repeats the form until you stop it

What changed

The quick change: the IV in bar 2 and back to the I in bar 3, so the form moves before you have settled. The turnaround in bars 11–12: I7, VI7, IIm7, V7, two beats each, instead of sitting on the I and then the V.

The turnaround is where the blues meets the jazz standard. Its last two chords, IIm7 to V7, are a ii–V — the most common progression in jazz; in A, Bm7 to E7. Learn to hear it here, over a shuffle, and you will recognise it in every standard you open.

Your pentatonic box here (in A)

Bar 2 now comes fast: arrive on D7 at the start of bar 2 with C or F♯ ready — the targets of step 1, one bar earlier.
F♯7 in bar 11 has an A♯, a note no blues box contains. Play it, then step up a semitone to B, the root of Bm7. That half step is the sound of the turnaround.
D is the third of Bm7 and the seventh of E7: hold it across both chords and let it fall a semitone to C♯, the third of A7, on bar 1. A♯–B, D–D–C♯: that is a guide-tone line, the tool jazz players use to make changes audible.
The A minor pentatonic still covers most of the form. Over F♯7 it gives A (the ♯9) and C (the ♭5): tense and bluesy, fine for two beats if the next note resolves.

The tips are in the step’s own key; in another key the same degrees apply. The pentatonics finder shows any pentatonic against any chord, note by note.

How to practise this step

In JamShed, loop bars 11–12 (Practice → bars) and play only A♯–B, D–D–C♯ until you hear the turnaround without looking at the chart.
Then the whole form with your box, but always arriving on D7 at the downbeat of bar 2.
Last, the guide-tone line at the end of every chorus, with the box everywhere else.