How to Write a Jazz Bass Line: In 2 & Walking Bass I MusicMyLanguage

Chapter 2

The Bass Line: Choose the Right Bass Line and You’re Golden

You can write a great melody. You can find beautiful chords. You can even have a killer drum groove.

But choose the wrong bass line — and somehow the whole arrangement just doesn’t sit right.

The bass is one of the most important links between harmony and rhythm.

It supports the chord progression, locks in with the drums, gives the music direction and, perhaps most importantly, helps determine how the entire arrangement feels.

And there isn’t just one way to do it.

As a composer or arranger, you have several basic approaches to choose from.

In this chapter of Inside The Arrangement, I’ll introduce some of the most useful ones, accompanied by audio examples and sheet music,

so you can both see and hear the difference.

But before we get to the notes, there is one important principle:

A great bass line doesn’t work alone.

The bass player needs solid support from the other rhythm-section players. Drums, piano and guitar all contribute to the groove and harmony.

When they work together, the bass line doesn’t merely support the melody - it helps carry the entire arrangement.

So, let’s get started.

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1. Playing “In 2”

When musicians say that the bass is playing “in 2,” it basically means that the bass emphasizes two notes within a 4/4 measure,

usually giving the music a spacious two-beat feeling.

It is simple - but simple does not mean boring.

There are several ways to create an effective in 2 bass line.

Root notes only

The simplest version is to play the root of the chord on beats 1 and 3.

This clearly establishes the harmony and gives the rest of the rhythm section plenty of space.

For better audible results please use headphones / proper in ears

Root notes — changing octaves

Now take the same basic idea but alternate between different octaves of the root.

The harmonic information hasn’t changed, but the line immediately has more movement.

Root and fifth

Another classic approach is to alternate between the root and fifth of the chord.

It is still harmonically simple, but the fifth adds another dimension and creates a stronger sense of motion.

Root and fifth — with a little rhythmic movement

We can make the same idea more interesting by introducing a small rhythmic phrase around beats 1 and 2.

Now the bass is beginning to do more than simply state the harmony. It starts contributing its own rhythmic character to the arrangement.

Root & Fifth with little Rhythmic Movement

Mixing “In 2” and quarter-note movement

Here is another useful variation.

Instead of maintaining exactly the same pattern in every measure, try a two-bar phrase:

Bar 1: two half notes

Bar 2: four quarter notes

The bass is still creating an overall in 2 character, but the second measure introduces forward motion.

This is a very simple arranging device — and a very effective one.

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2. Playing “In 4” — The Walking Bass Line

Now things start moving.

When the bass plays four quarter notes in a 4/4 measure, we call this playing “in 4.”

In jazz, this is commonly associated with the walking bass line.

And this is where understanding harmony becomes particularly important.

A good walking bass line shouldn’t simply play the root four times:

1 – 1 – 1 – 1

That would establish the chord — but after a while it would become rather boring.

Instead, the bass player uses chord tones, scale tones and passing notes to create a melodic line that connects one chord to the next.

This is also why the bass player needs a rhythm section that clearly supports the correct chords and chord progression.

The better the harmonic foundation, the more naturally the bass can create movement through the harmony.

Here are a few basic patterns to get started.

1 – 1 – 5 – 5

Root – Root – Fifth – Fifth

A very straightforward pattern and a good starting point for understanding the sound of four quarter notes against the harmony.

1 – 2 – 3 – 5

Root – Second – Third – Fifth

Now we are beginning to hear the line as something melodic rather than simply a sequence of chord root & fifth.

1 – 2 – 3 – 1

Root – Second – Third – Root

Another simple way of moving through the scale while keeping the root as a strong reference point.

1 – 7 – 6 – 5

Root – Seventh – Sixth – Fifth

Here the line moves downward, creating a completely different sense of direction.

These aren’t rules.

Think of them as building blocks (or pattern).

Once you understand what they do, you can combine them, change their direction and adapt them to the chord progression.

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What If the Chord Lasts Longer?

This is where things become even more interesting.

Suppose one chord lasts for two complete measures.

Playing exactly the same four-note pattern twice isn’t your only option.

You can create a longer melodic journey through the harmony.

For example:

1 – 7 – 6 – ♭6 | 5 – 4 – 3 – 2

Suddenly eight quarter notes form one continuous line.

And notice something important: the bass isn’t simply describing the chord anymore.

It is creating direction.

That is one of the secrets of a good walking bass line.

Every note should make you want to hear where the next one is going.

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Should You Write the Bass Line Out?

This depends entirely on who is going to play your arrangement.

An experienced professional jazz bassist usually doesn’t need every quarter note written out.

Give an experienced player a lead sheet or bass part containing the chord progression and tell them:

“In 2.”

or

“Walk in 4.” (or just “In 4”)

…and they will know what to do.

In fact, allowing a good bass player some freedom can often produce a more natural result than trying to notate every single note yourself.

But there is an important exception.

Writing for Student Bands

If you’re arranging for a school ensemble, developing jazz band or educational publisher, I recommend a different approach.

Write out a suitable bass line and include the chord symbols above it.

I would also mark the intended feel — for example:

In 2

or

Walking in 4

Why both?

Because you’re doing two things at the same time.

You’re giving a developing bass player something they can perform successfully right now,

while also showing them how a bass line relates to the underlying chord progression.

Eventually, they may stop needing the written notes.

And that’s exactly what you want.

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The Bigger Picture

The bass line is only one part of the rhythm-section puzzle.

A great bass player needs to know where the harmony is going.

The drummer needs to support the feel.

And piano and guitar have to provide the right harmonic and rhythmic framework without getting in the bass player’s way.

When all of those elements fit together, something wonderful happens:

The rhythm section stops sounding like four musicians playing individual parts.

It starts sounding like one instrument.

And that brings us perfectly to the next chapter of Inside The Arrangement:

Chapter 3: What Do the Piano & Guitar Players Do?

We’ll look at chord voicings, rhythmic comping, how piano and guitar can support the bass and drums -

and, just as importantly, how to keep them from stepping on each other’s toes.

See you in the next chapter.

Rolf Becker

Composer · Arranger · Conductor

MusicMyLanguage — Learn. Practice. Perform.

Inside The Arrangement