# The 12-bar blues

*Module 12 · Lesson 4: Pentatonic and blues · BazzLow*

> Know the standard 12-bar blues form and its common variants.

Before this lesson: [10.4 The dominant seventh](https://bazzlow.com/en/seventh-chords/dominant-seventh/) · [11.5 Swing and shuffle](https://bazzlow.com/en/rhythm-2/swing-and-shuffle/)

Twelve bars, three chords, and an enormous amount of music. If you can follow a 12-bar blues you can join most jam sessions.

## The form

The **12-bar blues** is a 12-bar chord pattern on **I, IV and V**, usually all **dominant 7th** chords (I7, IV7, V7). It repeats for every verse, called a **chorus**, of the song. In the standard form there is one chord per bar:

*The standard 12-bar blues, one chord per bar, in A and E.*

| Bar | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Chord | I7 | I7 | I7 | I7 | IV7 | IV7 | I7 | I7 | V7 | IV7 | I7 | V7 |
| A | A7 | A7 | A7 | A7 | D7 | D7 | A7 | A7 | E7 | D7 | A7 | E7 |
| E | E7 | E7 | E7 | E7 | A7 | A7 | E7 | E7 | B7 | A7 | E7 | B7 |

In A: A7 A7 A7 A7 | D7 D7 A7 A7 | E7 D7 A7 E7.

## Variants

- **quick change**: IV7 in bar 2 (I7 IV7 I7 I7 …);
- bar 10 stays on **V7** instead of IV7;
- bar 12 on **I7** at the very end of the song.

The **turnaround** is the last bar or two (bars 11–12), which lead back to bar 1. Here they end on V7, the dominant that pulls back to I. Short figures are played there to signal the return.

## Roots on the neck

The roots form an easy box: IV is on the next string up at the same fret, and V is two frets further.

> **Diagram:** The roots of I, IV and V in A: A at fret 5 on the E string, D at fret 5 on the A string, E at fret 7 on the A string.

> **Diagram:** The same box in E: open E string, open A string, B at fret 2 on the A string.

## Good to know

Blues lyrics often follow the pattern A–A–B: a line, the same line repeated, an answering line, a call and response in four-bar phrases. Common keys are E, A, G and the other keys comfortable for guitar; with horns, B♭, E♭ and F are common. The 12-bar blues is the base of much rock and roll, R&B and jazz. Recognising it by ear is essential for jamming.

## Try it

Play the roots of a 12-bar in A, one bar per chord, with a shuffle feel (lesson 11.5). Count the bars aloud.

## New terms

- 12-bar blues
- quick change
- turnaround
- chorus (blues)

Page: https://bazzlow.com/en/pentatonic-and-blues/twelve-bar-blues/