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Jazz Theory and Practice Module 6 a, b, c
Beyond Basic Blues; Counterpoint in Jazz The Bass Line
C. The Bass Line
The study of jazz harmony must include, at some point, some special attention to the bass line. In an ensemble it seems easy enough to “leave it
up to the bass player”, but there are many instances where the keyboard
player or guitarist must provide a bass line, and there are many jazz arrangements where a bass trombone or a baritone sax assumes a bass
function. Arrangers will sometimes only supply the bass player with chord changes, but there are many times when a fully notated bass line is
essential to the arrangement.
(a) The bass note is often just the root of the chord. There are many simple folksong accompaniments that only use the roots of the harmony in the
bass, and often this simple accompaniment seems the most appropriate for the style of the music.
6c1
(b) Using root/fifth in the bass. In various folk dances, ragtime, and older jazz styles a bass pattern alternating between the root and fifth
of the chord is very common. This pattern can be found frequently
in keyboard parts for the classic big band swing arrangements of the 1930s and 1940s. In these examples the chord root is almost always
a single note on the stronger beat, and the chord fifth is a single note on the weaker beat:
6a3
6a4
(c) Other chord notes; “Slash” chords. As shown in previous modules, various chord notes may be used as a bass note, especially to
produce better connections between chords and a smooth stepwise bass line. A frequent practice with chord symbols is to use a chord
name followed by a slash and a note name to indicate a bass note other than the root; example: Dm7/F, Dm/C. Notice that both these
examples are D minor-7th chords; in the first case the bass note “F” is indicated, in the second case the bass note “C” is indicated, which
actually produces a D minor-7th chord with the seventh on the bottom. It should be stressed that, in common practice, a slash is
not required to indicate a bass note other than the root; the choice is often left up to the keyboard or bass player.
The following example is shown with two bass lines, the first with
only chord roots, and the second with various notes (indicated as
“slash” chords)
6a5
This short example provides a number of points about playing and
writing bass lines:
(1) The chord symbols above Bass line 1 provide the basic harmonic structure for the example, and the performer would be free to
interpret them with any number of variations of the bass line, including Bass line 2. None of the “slash chord” symbols are
really required.
(2) If only chord roots are used, as in Bass line 1, there are a number of perfect consonances (octaves and perfect 5ths) that
emerge between the melody and the bass. This is acceptable at the beginning of the phrase, but as it continues there is a
“hollow” sound, especially if you listen to the melody and bass alone without harmony. The octaves are especially prominent
moving from the A7 measure to the Bm measure, because they
are parallel octaves; the bass line is really just following the melody.
(3) There are a number of places here where bass notes have been
chosen to produce stepwise motion. Since the third of the chord (D) is used in the third measure, using the fifth of the chord (C)
in the second measure produces a rising scale. The scale is continued up to E in fourth measure, and notice that an
Emin7(¯5) chord is interpolated before the A7 chord here: a II7
� V7 pattern. A descending scale is introduced in the fifth
measure by using a chord 7th passing downwards (Bm/A). Stepwise bass lines will be discussed further when we look at
walking bass patterns later in this module.
Here are some basic principles that usually apply to using bass notes
other than the root:
(1) On stronger beats the root is still the preferred bass note, but the third, and sometimes the fifth might be used, especially on
weaker beats. (2) If the root of the chord is a melody note, and is not at the end of
a phrase, it should not be the bass note. (3) If the third of the chord is in the melody, it usually should not be
used as the bass note. (4) For dominant-7th chords (and to a lesser extent, minor-7th
chords) any note can be used as a bass note. The two strongest notes of the seventh chord: the third and the seventh are
especially effective as bass notes, but should also resolve by
step. (5) For extended chords (9th, 11th, 13th), the extension, as a rule,
should not be used as a bass note. Remember that many extensions are most effective when they are heard above
another note in the chord: #9 above the 3rd, #11 above the 7th, 13th above the 7th.
In the previous example the second bass line turns out to be almost
entirely stepwise; the chord notes were obviously chosen to produce the stepwise line. In Module 6b we looked at various
examples of figuration, where a stepwise bass line is developed by including notes that don’t necessarily belong to the chord;
especially (P)assing notes and (N)eighbour notes, and (IN)complete neighbour notes.
Non-chord notes are absolutely essential in the walking bass lines
discussed in section (e).
(d) Pedal tones and ostinato patterns.
A pedal tone is simply a bass note that stays constant through different harmony changes, sometimes for an extended period of
time (even a full chorus). The pedal tone may be a note that belongs to the chord, or not.
Following are the opening measures of two jazz standards, and a
pedal tone is used in both cases (notice the use of slash chords here). In the first example the pedal tone lasts for six bars, only
two different chords are used, and the pedal tone belongs to both chords. In the second example the pedal tone lasts for only three
bars, but over six harmony changes, and two of the chords (which
ones?) do not contain the pedal tone. It’s interesting that the melody is also a pedal tone here, so the harmony is “sandwiched”
between repeated notes both top and bottom.
Ostinato patterns (riffs) are like a group of pedal tones in a cyclic
pattern. They may be based on one chord, or a pattern of two or
three chords. They might vary in length from a few beats to several
measures. A bass ostinato might be used in an up tempo chorus
driving a solo line over one or two chords. In a slow tempo an
ostinato might contribute an overall feeling of calm—as in various
genres of background music. Here is an example of a short ostinato
pattern, from “Angel Eyes”.
(e) Walking bass.
When providing a walking bass, either written out or improvised
during performance, there are two important assumptions:
(1) The bass part will usually include a note on every pulse. The pulse is most often in quarter notes.
(2) The root of the chord will often be in the bass part where
the chord changes, especially on the down beat.
There are exceptions to both of these assumptions. Often a steady stream of quarter notes will be broken by an empty beat, or a dotted-
quarter-eighth pattern, or a pair of eighths, especially to give extra emphasis; at the beginning of a new phrase, for example. For the
new chord change, notes other than the root, especially the third,
might be used where the note is a good stepwise connection from the previous bar.
Walking bass should be stepwise about 95% of the time, although
there are some jazz writers that use the walking bass label for any steady quarter-note pattern, stepwise or not. Repeated notes are not
usually characteristic of walking bass, although occasionally they may be used for variety. Even when the harmony doesn’t change from one
bar to the next, the bass should “keep walking”.
There is a standard repertoire of typical walking bass patterns. Most patterns use what many jazz musicians call “approach tones” at the
end of the pattern, which means that the note on the next downbeat is approach by step or half step. Half steps usually work the best, and
sometimes two or three are used in a row. Choosing an appropriate
pattern requires the performer, or arranger, to look into the immediate future. What is the distance to the next bass note? There aren’t as
many options as you might think:
(1) Most common: up a fourth, up a fifth. (Remember, this also means down a fifth or down a fourth)
(2) Common: up a second, down a minor second. (3) Less common: up or down a third, down a major second.
The final option is where there is no chord change. The following
patterns are “static”, and would typically be used at the end of a phrase, or where there is no chord change in the following bar:
6c5
The pattern in (a) above is just an arpeggio on the Bb chord.
The simple variation of the pattern in (b) is more effective because
the root of the chord is delayed until the downbeat of the second bar, using an “approach tone” (circled). Both examples (b) and (c)
approach the new downbeat by step. The scale pattern in (c), rising
from the fifth of the chord, is used often. The pentatonic bass line in
(d) matches the Bb6 chord.
The following pattern is used often for harmonic movement up a
fourth:
6c6
There are various ways to describe this bass pattern: (1) there is a
strong feeling of two or three “approach notes” leading to the new chord, because of the chromatic motion. The pattern consists of a
whole step (W) followed by three half-steps (H), or and it can also be
heard as a rising scale using both the minor third and the major third
of the chord. For this reason, the pattern works equally well with either the Cm7 chord or the C7 chord in the example above.
Here are two other patterns that work for a rising fourth:
6c7
The first pattern moves from the root to the third of the chord and back; the second pattern is an octave drop with a rising scale,
especially effective at the end of a phrase.
The following example shows a combination of various patterns for rising fourths. Each rising fourth pattern is bracketed under the
music:
6c8
The rising fourth is by far the most common harmonic movement in
jazz harmony, but a rising fifth does happen frequently. The following patterns are typical for harmonic movement up a fifth:
6c9
Both patterns use three half-steps in a row. The first pattern begins
with an upward third; the second pattern is the rising fourth pattern upside-down. The following sequence combines upward fourths and
fifths:
6c10
The following patterns are typical for rising seconds; notice how the new downbeat has two chromatic “approach notes”.
6c11
Here is a sequence of dominant-7th chords descending by half-steps,
with two walking bass patterns:
6c12
Finally, two patterns for descending thirds. This chord sequence is
often used for a “turnaround” (returning to the tonic chord).
6c13
(f) Something to Listen To:
There are a number of absolutely wonderful jazz bassists. Two that come to mind are Ray Brown, who for many years played bass with
Oscar Peterson, and the Canadian Dave Young, who also played with Peterson, many other jazz greats, and sometimes plays bass in the
Toronto Symphony as well. Here are some samples:
Lady be Good. Ray Brown Trio. Get past the intro to hear the walking bass behind the tune.
Round Midnight. Dave Young Quartet. Lots of descending stepwise bass lines. There are many Dave Young links on YouTube.
…an interesting jazz novelty:
Music Gallery- John Clayton – The Walking Bass. https://www.youtube.com/watch?v=F1v4vW4WWfc
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