Playing the 12-Bar Blues
The 12-bar blues is one of the world's most familiar musical forms, and one of the simplest to study, play and enjoy.
This form began in the early days of jazz, a music that developed from the melancholy songs, spirituals, and call-andresponse "hollers" that were a common form of communication and expression among African-American slaves throughout the South.
As popular music became a vehicle of personal expression and improvisation in New Orleans, St. Louis, Chicago and other big-city entertainment districts, composers developed forms and chord progressions that would be familiar to players as well as their listeners.
In 1914, W.C. Handy wrote "St. Louis Blues," beginning the modern era of the 12-bar blues, still a compositional staple of rock, blues, jazz and many other styles.
The chord progression I-IV-V-I is the basis of the 12-bar blues, which is nearly always written in 4/4 time (four quarter notes to a bar).
The Roman numerals indicate the individual notes of the scale. In the key of C, for example, a 12-bar blues uses three basic chords: C (I), F (IV), and G (V).
A very common structure for a 12-bar blues is to write four bars in C, two bars in F, two bars in C, one bar in G, one bar in F, and two "turnaround" bars in C.
The final bar often brings the tune back to the "tonic" I chord with a V7 chord (in the key of C, this chord would be spelled G, B, D, and F).
Using this simple structure, an infinite number of elaborations and variations are possible.
The final four-bar cadence, for example, can bring the music through a II-V-I progression, giving the musician an additional scale to use.
Blues harmony welcomes extended chords - the seventh note of the scale can always be added when you're moving through a progression.
As in all blues music, the standard major scale is often altered by flattening the third and seventh notes of the scale; in C major, for example, E-flat and B-flat stand in for E and B, lending the music its familiar sound of anger and sadness.
Skilled blues musicians won't hesitate to add chromatic runs and minor-key variations to the standard progression.
In the lyrics to their songs, blues composers follow an AAB pattern for the 12-bar blues.
Each 12-bar section comprises a lyrical stanza, which is divided into three lines; the first line is repeated by the second (the AA part), while the last line resolves or answers the previous two (the B part).
Muddy Waters, John Lee Hooker, Chuck Berry, B.B. King and other blues greats favored this form for slow ballads, moderato "walking" blues and lightning-fast jams.
Over the years, the 12-bar blues was picked up by myriad jazz composers who extended the length of the basic form and substituted new chords while reminding listeners of the basic I-IV-V-I architecture.
John Coltrane, Miles Davis, Herbie Hancock and Chick Corea all have written and performed 12-bar compositions, which can provide a flexible form for extended improvisations.
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