Chord progressions
The 12-bar blues chord progression
The 12-bar blues spreads I, IV and V over twelve bars, usually as dominant seventh chords: four bars of I7, two of IV7, two of I7, then V7, IV7, I7 and V7 to turn around to the start. In C it is C7 – C7 – C7 – C7 – F7 – F7 – C7 – C7 – G7 – F7 – C7 – G7.
Hear it, then play it
Play each chord in turn: press all of its notes, in any order and any octave, before moving on. The chords are in C major.
The form, bar by bar
Bars 1–4: I7. Bars 5–6: IV7. Bars 7–8: I7. Bar 9: V7. Bar 10: IV7. Bar 11: I7. Bar 12: V7, the turnaround that leads back to bar 1. Many players use IV7 in bar 2 (the quick change) and I7 in bar 12 on the last chorus.
Songs that use it
"Johnny B. Goode" by Chuck Berry and "Hound Dog" as sung by Elvis Presley follow the 12-bar form, as do countless blues songs and rock and roll hits.