Twelve-bar blues

src: www.learnjazzstandards.com

The twelve-bar blues or blues changes is one of the most prominent chord progressions in popular music. The blues progression has a distinctive form in lyrics, phrase, chord structure, and duration. In its basic form, it is predominantly based on the I, IV, and V chords of a key.

The blues can be played in any key. Mastery of the blues and rhythm changes are "critical elements for building a jazz repertoire".

Video Twelve-bar blues

Structure

In the key of C, one basic blues progression (E from above) is as follows. (For the most commonly used patterns see the section "Variations", below.)

Chords may be also represented by a few different notation systems such as sheet music and electronic music. A basic example of the progression would look like this, using T to indicate the tonic, S for the subdominant, and D for the dominant, and representing one chord. In Roman numeral analysis the tonic is called the I, the sub-dominant the IV, and the dominant the V. (These three chords are the basis of thousands of pop songs, which thus often have a blues sound even without using the classical twelve-bar form.)

Using said notations, the chord progression outlined above can be represented as follows.

The first line takes four bars, as do the remaining two lines, for a total of twelve bars. However, the vocal or lead phrases, though they often come in threes, do not coincide with the above three lines or sections. This overlap between the grouping of the accompaniment and the vocal is part of what creates interest in the twelve bar blues.

Variations

"W.C. Handy, 'the Father of the Blues', codified this blues form to help musicians communicate chord changes." Many variations are possible. The length of sections may be varied to create eight-bar blues or sixteen-bar blues.

In the original form, the dominant chord continued through the tenth bar; later on the V-IV-I-I "shuffle blues" pattern became standard in the third set of four bars:

 Play 

The common quick to four or quick-change (quick four) variation uses the subdominant chord in the second bar:

These variations are not mutually exclusive; the rules for generating them may be combined with one another (or with others not listed) to generate more complex variations.

Seventh chords are often used just before a change, and more changes can be added. A more complicated example might look like this, where "7" indicates a seventh chord:

When the last bar contains the dominant, that bar may be called a turnaround; otherwise the last four measures is the blues turnaround.

 Play 

In jazz, twelve-bar blues progressions are expanded with moving substitutions and chordal variations. The cadence (or last four measures) uniquely leads to the root by perfect intervals of fourths.

The Bebop blues:

 Play 

This progression is similar to Charlie Parker's "Now's the Time", "Billie's Bounce", Sonny Rollins's "Tenor Madness", and many other bop tunes. "It is a bop soloist's cliche to arpeggiate this chord [A^7?9 (V/ii = VI^7?9)] from the 3 up to the ?9."

Minor blues (Spitzer 2001, p. 63)  Play 

There are also minor twelve-bar blues, such as John Coltrane's "Equinox" and "Mr. P.C.", and "Why Don't You Do Right?", made famous by Lil Green with Big Bill Broonzy and then Peggy Lee with the Benny Goodman Orchestra. The chord on the fifth scale degree may be major (V⁷) or minor (v⁷), in which case it fits a dorian scale along with the minor i⁷ and iv⁷ chords, creating a modal feeling. Major and minor can also be mixed together, a signature characteristic of the music of Charles Brown.

While the blues is most often considered to be in sectional strophic form with a verse-chorus pattern, it may also be considered as an extension of the variational chaconne procedure. Van der Merwe (1989) considers it developed in part specifically from the American Gregory Walker, though the conventional account would consider hymns to have provided the repeating chord progression or harmonic formulae of the blues.

Maps Twelve-bar blues

Lyrical patterns

The lyrics of most blues songs consist of verses of three lines, of which the first two are the same or vary slightly in wording, often with an interjection in the second line:

I hate to see the evening sun go down,

Yes, I hate to see that evening sun go down
'Cause it makes me think I'm on my last go 'round

However, many songs using the blues chord progression have lyrics that are not in the three-line form. For instance, "I'm Moving On" has a verse in the first four bars and a chorus in the final eight bars:

That big eight-wheeler rollin' down the track

Means your true lovin' daddy ain't comin' back.

I'm movin' on, I'll soon be gone
You were flyin' too high for my little old sky
So I'm movin' on.

Here is an example showing the twelve-bar blues pattern and how it fits with the lyrics of a given verse. One chord symbol is used per beat, with "-" representing the continuation of the previous chord:

  I        -     -      -      IV     -   -    -             I - - - I7 - - -  Woke up this morning with an awful aching head    IV        -     -      -     IV7    -   -    -             I - - - I7 - - -  Woke up this morning with an awful aching head    V     -        -     V7      IV    -    -     IV7          I - - - I - V V7  My new man had left me,      just a room and an empty bed.  

Another example, "Johnny B. Goode" (written and first recorded by Chuck Berry), applies a "shuffle" or "light 'swing'" rhythm to one of the more common twelve-bar progressions:

src: www.12barbluesbass.com

Notes

src: i.ytimg.com

References

src: d2r5da613aq50s.cloudfront.net

Sources

• Benward, Bruce, and Marilyn Nadine Saker (2003). Music: In Theory and Practice, Vol. I, seventh edition. Boston: McGraw-Hill. ISBN 978-0-07-294262-0.
• Covach, John. "Form in Rock Music: A Primer", in Stein, Deborah (2005). Engaging Music: Essays in Music Analysis. New York: Oxford University Press. ISBN 0-19-517010-5.
• Doll, Christopher (2009). "Transformation in Rock Harmony: An Explanatory Strategy". Gamut (2): 1-44. 
• Jackson, Fruteland (2002). Beginning Delta Blues Guitar. Alfred Publishing. ISBN 978-0-7390-3006-6.
• Gerow, Maurice and Tanner, Paul (1984). A Study of Jazz, Dubuque, Iowa: William C. Brown Publishers, p. 37, cited in Baker, Robert M. (2005).
• Greene, Ted (1971/1992). Chord Chemistry: For Guitar. Alfred Music. ISBN 9781457455292.
• Kernfeld, Barry, ed. (2007). "Blues progression". The New Grove Dictionary of Jazz;. 2nd Edition. Oxford, UK: Oxford University Press. 
• Middleton, Richard (1990/2002). Studying Popular Music. Philadelphia: Open University Press. ISBN 0-335-15275-9.
• National Guitar Workshop (2003). Electric Bass for Guitarists. Alfred Publishing. ISBN 0-7390-3335-2.
• Spitzer, Peter (2001). Jazz Theory Handbook. Mel Bay. ISBN 978-0-7866-5328-7.
• Thomas, John (2002). Voice Leading for Guitar: Moving Through the Changes. Berklee Press. ISBN 0-634-01655-5.
• van der Merwe, Peter (1989). Origins of the Popular Style. Oxford: Clarendon Press. ISBN 0-19-316121-4. Cited in Middleton (1990).

src: i.ytimg.com

Further reading

• Axelsson, Lars; Strängliden, Eddie, eds. (2007). "Johnny B. Goode". 100 Lätta Låtar: Gitarr [100 Easy Songs: Guitar]. 100 Lätta Låtar. 1. Erhrlingförlagen AB. Arc Music Corp. ISBN 978-91-85662-11-1. 
• Shipton, Alyn (2007). A New History of Jazz, 2nd. ed., Continuum, pp. 4-5. ISBN 9780826429728.

src: www.learnjazzstandards.com

External links

• Anonymous (8-14-08). "Blues Chord Progressions and Variations: Common variations in the twelve bar form", How to Play Blues Guitar.com.

Source of the article : Wikipedia