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Jazz Theory and Practice
Module 6 a, b, c
Beyond Basic Blues; Counterpoint in Jazz;
The Bass Line
Beyond Basic Blues
A. Minor Blues and 8-bar blues: Probably at least 90% of the blues that
are played/sung in jazz are firmly rooted in the basic 12-bar structure
introduced in Module 4. There are two important variations on that
fundamental structure however: the minor blues and the 8-bar blues.
The relationships among the three patterns are shown in the figure
below:
6a1 © 2016 Peter J. Clements
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The “standard blues” is the basic harmonic pattern introduced in Module 4.
The 8-bar blues uses the same sequence of chords; the plagal and cadential
progressions are preserved, but abbreviated to 5 bars + 3 bars. The minor
blues typically maintains the 12-bar sequence with both the I and the IV
chords in their minor form; the V chord is usually major to produce a
stronger cadential progression.
As was shown for the “standard” blues in Module 4, neither the 8-bar blues
nor the minor blues would ever appear as the simple harmonic structure in
the previous example. Here is a more elaborate version of the 8-bar blues,
shown together with the basic harmonic formula. Notice the extended
cadential progression using a circle of fifths:
6a2
As was shown in Module 4, the dominant-7th chords (C7, F7) are used to
support the “blue notes”. At the end of the plagal progression the Fm7
chord passes chromatically back to C. The cadential progression is
extended with a circle of fifths: Am7 � Dm7 � G7 � C.
Here is an interesting harmonic variation of the minor blues progression,
based on Blue Trane by John Coltrane; it’s shown together with the basic
minor blues harmonic formula. A distinctive feature of this example is the
repeated use of the “modal cadential progression”: IV7 � VII7 � I. All of
the scales belonging to the minor scale family (Aeolian, Dorian, Phrygian)
use the lowered 7th step (the subtonic, not the leading tone), and a minor V7
� I is often avoided; it is regarded as less “final” than VII7 � I (minor).
The “modal cadence” is common in folksongs and fiddle tunes, and is
frequently used in the Mixolydian scale.
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6a3
B. Harmonic development: integrating circles of fifths.
With the basic harmonic design of the blues well-established in our aural
memory, it’s easy to imagine anticipated harmonic goals in each part of
the form:
I ���� IV ���� I ���� V ���� I
Plagal Cadential
In the previous example (6a2) of an 8-bar blues the arrival of the
cadential progression (with G7) is anticipated and delayed by a short circle
of fifths: Am7 � Dm7 � G7.
The following shows the basic minor blues together with a more
complex version. It includes a circle of fifths before the arrival of the
cadential G7, but the circle leads to ¯VI, which then falls to V7 (like a tritone
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substitution). Within the plagal progression notice the two interpolations of
II � V � I (also circles of fifths) leading first to the IV, then back to I.
6a4
The next example is a “standard” 12-bar blues form that avoids the tonic
harmony and the plagal progression at the beginning, replacing the first 4
bars with a long chromatic circle of fifths leading to IV. After the arrival on
IV a descending chromatic sequence (B¯ � A � A¯) leads to the final II7 �
V7 � I7. Notice that the chords within the sequence do form a
“chromatically altered” circle of fifths, alternating perfect 4ths with
augmented 4ths
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6a5
6a5
C. Harmonic Development with Neighbour Chords
In traditional music theory “neighbour chords” are very common, and
have an important prolonging function. They are usually identified as part
of a three-chord sequence, where the first and third chords are identical or
almost identical, and the middle chord is connected by stepwise movement.
It is not really a chord progression; the stepwise movement diminishes the
importance of the middle chord, so the overall effect is one of prolonging the
initial harmony. The following examples show several examples of
prolongations using neighbour chords; notice the example where the first of
the three chords is missing: an incomplete neighbour chord.
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6a6
Example A (Killer Joe). Other than the bridge, this entire piece oscillates
between the tonic chord (C13) and the B¯13 (lower) neighbour chord.
Example B (Black Coffee). In this example the neighbour chord is up a half-
step. Upper neighbour chords are almost always a half-step, and lower-
neighbour chords are usually down a whole step.
Example C (Born to Be Blue). This is an 8-bar minor blues. The tonic chord
(C7) moves up a half-step to D¯7 neighbour chord, then the IV chord (F7) is
approached from an upper neighbour (G¯7). Following the model from
classical harmony, we can call this an incomplete neighbour (IN) because
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there is no F7 preceding. The C-G¯ progression is also, of course, a tritone
substitution.
Example D (All Blues – last 4 bars) uses an upper neighbour chord with the
dominant in the cadential progression, and Example E (Equinox – last 4
bars) uses an incomplete neighbour before the dominant.
A common feature of all these examples is that the neighbour chord
could be omitted in every case, and the basic harmonic sense doesn’t
change. The same principle can be applied to a blues progression by
interpolating neighbour chords. In practice these are usually chords with a
root either a whole-step below, or a half-step above. In traditional
harmony the neighbour function is often created in the bass with an inverted
chord; not so in jazz harmony where inversions are usually not specifically
identified. They tend to occur according to the voicing.
D. Parallel Harmonic Progressions: “passing chords”
In Module 4 downward stepwise chord sequences were introduced as (1) a
common turnaround, and (2) as a variation of the “rhythm changes”:
(1)
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(2)
6a7/6a8
Just as single neighbour chords can be inserted (interpolated) in the
middle of a harmonic structure, so can a group of “passing chords”
moving from one important harmony to another. Just as with the
neighbour chords, these short parallel progressions could be omitted
without changing the essential harmonic progression. Here is an
example that is often used before the cadential progression in a blues:
6a9
In this example (key: C major) the harmony moves from I to VI,
setting up the II – V – I cadential progression. The two middle chords
set up a descending chromatic parallel progression, but they could be
easily omitted.. Parallel harmonic progressions typically are:
a. Descending
b. All of the same chord type
c. Metrically weak…leading to the “arrival chord” on a strong beat.
E. Extended Chromatic Harmony
This final example, from Blue After Two by John Fedchock, shows two
harmonizations of a standard 12-bar blues form, one written above the
other. The bottom version, in lead-sheet format, is the simplified
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version in 7th chords, and the upper version, with chord symbols and
keyboard voicing, is an expanded chromatic version:
6a10
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This example also appears in the Play/Sing section following. Listen
to it in Finale, and try playing the piano voicing at the keyboard
(watch the accidentals carefully!). Some chords may sound harsh to
your ear; test the sound with different voicings. Some harmonic
analysis:
In the simplified version, notice the A¯7 added to the plagal
progression, leading back to the tonic (¯VII7 � I7). The tonic chord is
avoided at the end; the last two bars are really a turnaround, with B7
used as a tritone substitution for F7.
In the chromatic version a “comping rhythm” is suggested; much of it
matches similar rhythms in the horn parts. Comparing the two
harmonizations provides a wonderful lesson in advanced jazz
harmony:
Bar Chord(s) Chromatic Variation
1 I7 F - B¯ with extensions (V7 – I7)
2 IV7 E9(TT sub for I) – E¯9sus (I7 – IV7)
3-4 I7 (all with extensions)
F (IN) – F# - B – E (circle of 5ths leading to E¯)
5-6 IV7 – ¯VII7 B¯ - E¯ with ext. (I7 – IV7 like bar 2)
7 I7 B¯ - Am (P) with ext. passing down to G
8 VI7 G13 (#11) (VI7)
9-10 II7 – V7 C - D¯ (TT) - G - G¯ - F (II7 – then P down to F)
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II7-V7-#I7- II7-V7
Chords are extended. #I7 (TT for V) avoids tonic, and initiates turnaround.
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Something to listen to:
Equinox. Minor blues – straight ahead. Look for the Coltrane version.
Blue Trane. Minor Blues; listen for modal cadences (VII – I; IV – V).
-- Look for the Coltrane single (not the album)
Black Coffee (N). Standard 12-bar blues, with prominent N chords.
-- Find the version by Peggy Lee.
Mr. PC. Minor blues with prominent N chords. Find the version by
John Scofield and McCoy Tyner
Born to be Blue. 8-bar blues with bridge; both upper- and lower- N
chords. Look for the Mel Torme (also the composer) version.