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