396. CHROMATIC TONALITY AND ALL 7 MODES MODULATIONS OVER THE RHYTMIC AND HARMONIC PATTERN OF 12-BARS BLUES.

 

CHROMATIC TONALITY AND ALL 7 MODES MODULATIONS OVER THE  RHYTMIC AND HARMONIC PATTERN  OF 12-BARS BLUES.

In the blues (that may be somehow considered a type of rapsody concept collective composition and improvisation) the rhythm is  also standardized to e.g. 12-bars blues, which corelated the rhyrhmic measures with the sequence and duration of the 3 chords 1M, 4M 5M or  1M 2m 5M.

1M 1M 1M 1M 4M 4M 1M 1M 5M 5M 1M 1M    It is standard in tonal harmony that we may substitute a chord with another which is usually one of its minor relative chords. Thus here in this pattern we may substitute 1M  with 6m or 3m 4M with 6m or 2m  e.g. if we substitute 4M with 2m then  1M 1M 1M 1M 2m 2m 1M 1M 5M 5M 1M 1M

And we may subtitute 

5M with 3m or  7d

But more generally in chromatic tonality we may substitute one of the basic 3chords with some ofthe chords of the chromatic tonality thus we may substitute

1M  with 3M or 6M (besides 3m, 6m)

4M with 2M or 6 M (Besides 2m, 6m)

5M with 3M or 7M. (besides, 3m, 7d) 

e.g. 

1M	1M	1M	1M
2m	2M	6M	6M
3M	5M	1M	1M

When making the substititutionw it is good to keep the rule of the previous article, that is

 60% harmonic chord transitions, 30% melodic transitions, 10% superchromatic transitions. 

As alternative methods we have that the chord progression of the 12 bars blues can be shifted to all the 7 modes ofthe diatonic scale, so that it can produce different tonal or chrmatic tonal 12-bars blues 

Here are all the 7 modes of the chord progression for the 12 bars blues

IONIAN                  1M 4M 1M 5M 1M 

DORIAN                 2m 5M 2m 6m 2m

FRYFIAN                3m 6m 3m 7d 3m

LYDIAN                  4M 7bM 4M 1M 4M  (chromatic tonality because of the 7b)

MIXOLYDIAN        5M 1M 5M 2m 5M

AEOLIAN                6m 2m 6m 3m 6m

LOCTIAN                7d 3m 7d 4#M 7d  (chromatic tonality because of the 4#)