12-Bar Blues in E

The definitive 12-bar blues form in E — the most played key for guitar blues because all three chords (E7, A7, B7) are open-position dominant sevenths. The I7 (E7) lasts four bars, the IV7 (A7) enters at bar 5, and the V7 (B7) peaks at bar 9 before the turnaround. Every blues guitarist must know this cold.