bassist, author, clinician, educator
January/February
1999
Chord Study: Blues in F (Part 2)
by Michael Dimin
Last time, I presented 12 measures of a blues in F played in a simple "comping" style.
In this lesson I will add harmonic interest through reharmonization techniques.
Reharmonization or chord substitutions are jazz techniques that add interest
to the harmony. Reharmonization is too complex to fully explain in this lesson.
I will give you three examples and the theory behind them. Play this chorus
and learn the sound of these reharmonizations. You might be surprised how often
you hear them being used. The three reharmonization techniques in this chorus
are the "II-V", the "Substitute Dominant" or "Sub
V", and Root Motion.
In the "II-V" substitution, any chord can be preceded by a chord
progression made up of chords based on the 2nd and 5th scale degree of that
chord's scale. For example, the F7 in measure 11 is preceded by its "II",
a Gm7 in measure 9 and its "V", a C7 in measure 10. The Gm7 in measure
9 is preceded by its related "II" the Am7(b5) and its related "V" the
D7(b9) in measure 8.
In a "Sub V", a dominant 7th chord is being replaced by a dominant
7th chord a tritone away (augmented 4th or diminished 5th). A dominant 7th
chord has a strong need to resolve to a tonic chord due to the interval between
the third and seventh of the chord, a tritone. The dissonance of this augmented
fourth wants to resolve inward to the root and third of the tonic chord. For
example, the E and Bb of a C7 chord want to resolve inward to the F and A of
an F chord. The "Sub V" substitution is possible because two dominant
7th chords a tritone away share the same guide tones (third and seventh). For
example an F7 (F,A,C,Eb) and a B7 (B,D#,F,A) share the same guide tones (A
and Eb or D#). Here are three "Sub V" examples. The first is on the "and" of
beat 2 in measure 4 where a B7 replaces the F7 resolving to the Bb7 in measure
5. The second is in measure 11 where an Ab7 is substituted for a D7 resolving
to a G7 in measure 12. Finally, in measure 12 a Gb7 is substituted for a C7
resolving to F7 at the top of the form. (Please note that the measure 11 and
12 are based on a I-VI-II-V turnaround).
Root motion is the building of a chord off of a new root that is moving stepwise
or chromatically. For example, I have substituted a Bdim7 for Bb7 in measure
6. The Bdim7 actually substitutes for a Bb7(b9), giving chromatic motion in
the bass from Bb to B to C (of the F chord). The other example comes on beat
3 of measure 7. I have added a Gm7 as a diatonic stepwise chord leading from
the F7 on beats 1 and 2 to the Am7(b5) on beat 1 of measure 8.
There is one other reharmonization that I did not mention it is the F#7 on
beats 3 and 4 in measure 3. Although the F#7 does not actually substitute for
a C7 (see "Sub V"), I have used the same basic technique. I preceded
the F7 in measure 4 by its substitute dominant - F#7.
You have really come a long way. This chorus could easily be played as a "comp" behind
a soloist or as a bass solo. Give it a try. Next issue we will add a walking
bass line. Remember to make it swing!