The most played chord chart in jazz and rock: three four-bar phrases over three seventh chords, I, IV and V, with a call, its response and blue notes.
C major · 4/4 · 96 beats per minute · 24 bars · 1 min 00 · intermediate level
no account needed
Twelve bars, three phrases
The twelve-bar blues is one of the most played chord progressions in popular music. The blues was born in the
American South, and its chart took shape in the early twentieth century: W. C. Handy published
The Memphis Blues in 1912, then St. Louis Blues in 1914. You will find it everywhere after that, in jazz
(Duke Ellington's C Jam Blues, from 1942, is a blues in C, like this lesson) as well as in rock'n'roll
(Hound Dog, sung by Big Mama Thornton and then by Elvis Presley).
Its twelve bars fall into three phrases of four. In a sung blues, the first phrase is repeated, barely changed, then
the third one answers it: this form is written A A' B. That is exactly what I find in this lesson, and the
chord chart follows the same split:
Bars 1 to 4: C7 for four bars. This is the home chord, the I.
Bars 5 to 8: F7 for two bars, the IV, then back to C7 for two bars.
Bars 9 to 12: G7, the V, then F7, C7, and G7 again in the last bar to start the
chart over: that is the turnaround.
Three chords, always in the same order: once this chart is in your ear, you will hear it in thousands of
songs.
Three seventh chords, and blue notes
In the blues, all three chords are seventh chords: C7 (C, E, G, B-flat), F7 (F, A, C,
E-flat) and G7 (G, B, D, F). In classical harmony, only the chord built on the fifth degree carries
that kind of seventh, and it calls for the chord a fourth higher. That is why the map writes V7/IV under
C7: read the classical way, it announces F. In the blues, it is at home; that seventh gives it its sound.
The other hallmark of the blues is its blue notes: the minor third, the augmented fourth and the minor seventh,
played against major chords. In C, they are E-flat, F-sharp and B-flat, which together with
C, F and G make up the blues scale. The right hand's call starts precisely on an E-flat
that slides up to the chord's E: that rub is the sound of the blues.
What the lesson plays
The lesson goes round the chart twice, in twenty-four bars.
A (bars 1 to 4): the call (E-flat, E, G, B-flat, G, then a held
C), and its response, which comes back down to low C.
A' (bars 5 to 8): the same phrase, note for note, but over F7: only the chord has changed, and the
melody takes on a different feel. Going from F7 back to C7 makes a plagal cadence, the "amen" of hymns.
B (bars 9 to 12): the right hand draws each chord from the top down (D, B, G, F over G7;
E-flat, C, A, F over F7), lands on C, then the turnaround climbs up G7 (D, F, G,
B) to start again.
The second chorus (bars 13 to 24) repeats the same right hand and ends on a C7 chord.
It is the left hand that changes from one chorus to the next. In the first, it holds each chord in half notes, with
three notes: the root, the third and the seventh. In the second, it plays a stride-like pump: the root on beats 1 and
3, the third and seventh on beats 2 and 4. Watch those two notes when C7 moves to F7: E drops to
E-flat, B-flat to A. These are the guide tones: they are enough to make the chord heard,
and they move by a half step.
The form
The sections of the piece and their chords: the map you learn before playing a single note.
A A' B A A' B'
Section
Bars
Chords
Phrase ending
A
1–4
C7 V7/IV
—
A'
5–8
F7 · C7 IV7 · V7/IV
Plagal cadence
B
9–12
G7 · F7 · C7 · G7 V7 · IV7 · V7/IV · V7
Imperfect cadence
A
13–16
C7 V7/IV
—
A'
17–20
F7 · C7 IV7 · V7/IV
Plagal cadence
B'
21–24
G7 · F7 · C7 V7 · IV7 · V7/IV
Plagal cadence
The key
C major
No sharps or flats
Scale
C · D · E · F · G · A · B
Pillar chords
I = C · IV = F · V7 = G7
The tricky passages
Bar 3: notes outside the key
Bar 7: notes outside the key
Bar 13: a melodic leap (minor sixth), notes outside the key
How to approach it
My plan takes you through it in 9 days. The goal is not just to play these twenty-four bars: it is
to keep the chart in your fingers, so you can spot it and play it anywhere.
Learn the chart by heart, without playing. Count the twelve bars out loud, naming the chords:
C, C, C, C, F, F, C, C, G, F, C, G.
Start with the left hand alone. The three chords (C, E, B-flat; F, A, E-flat;
G, B, F) in the order of the chart, in half notes, until you can chain them without looking; then the pump of
the second chorus. Over F7 and G7, it puts the seventh below the third (E-flat, A;
F, B), so each guide tone moves only a half step or a whole step.
The right hand's call: slide from E-flat to E with the same finger, from the black key to the
white one. It is the blues gesture on the piano.
The passages I point out are mostly notes outside the C major scale (bars 3 and 7): they are the blue notes,
and they are meant to be there. In bar 13, the second chorus starts with a leap, from the turnaround's B to the
call's E-flat: prepare it with your eyes on the landing note.
Swing the eighth notes. The file plays them evenly, so you can hear every note; once your hands are
together, play them "long-short", the way jazz swings.
Then improvise. Keep the left hand going, and invent your own calls with the blues scale (C, E-flat, F,
F-sharp, G, B-flat). As long as you follow the chart, you cannot get lost.
The plan: 9 days
Half an hour a day. First I help you understand the map of the piece, then we lay down the chord framework, learn each section phrase by phrase, work on the tricky passages, put it together and bring it up to tempo, until you can play it from memory.