How to play the blues scale on guitar

Tired of running up and down the minor pentatonic and still not getting that distinct, bluesy quality? Make way for the blues scale!

After you’ve got your pentatonic patterns down, the blues scale is the next step to a more authentic blues guitar sound.

In this article, we’ll cover:

• What makes a blues scale
• How to find the scale on the fretboard
• Guitar exercises for the blues scale
• Examples of the blues scale in use

What is the blues scale?

For most guitar players, the blues scale is often discovered by accident.

The blues scale is a six-note scale built using the familiar structure of the minor pentatonic.

• The essential difference is the addition of the b5th – known as ‘the blue note’.
• Blues and rock guitarists love to use this scale as a way to level up their minor pentatonic licks with some soulful, bluesy tension.

Want to hear the blues scale in action? Check out our 1-minute run down of the blues scale!

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Let’s dig a little deeper to find out what makes the blues scale so much fun to use.

The blue note

Before we jump into some useful fretboard exercises, let’s have a quick history lesson on the mysterious ‘blue note’ and why it has such an interesting reputation.

• ‘Blue notes’ are typically thought of as the notes in between regular scale notes.
• Their job is to create dissonance between the target notes of the scale.
• This can be an unsettling sound to some, but one of the key traits heard in the blues is the sound of tension and release.

More specifically, the blue note is the b5th of the scale.

• When we add it to the minor pentatonic, we get a chromatic sequence of three notes.
• It starts on the 4th, rises to the b5th, and lands on the regular 5th.
• Chromatic lines are usually quite difficult to get right, but the blues scale makes them a walk in the park!

The guitar is perfect for soulful lines. Unlike most instruments, we can mimic the fluidity of the human voice by bending notes.

• The blue note is the middle note between the 4th and the 5th.
• Guitarists will often bend the 4th and hit the blue note on their way up to the 5th.
• In jazz, the blue note can be identified as an ‘approach tone’ because of how it naturally wants to resolve up a semi-tone to the 5th of the chord.

What’s with all the tension?

Throughout history, musicians and composers have had a funny relationship with the b5th and the tension that the sound creates.

When combined with the root note of a scale, the  b5th is known as the tritone interval and many think this to be the most dissonant interval.

• Centuries before the blues existed, the blue note was referred to as ‘the devil’s interval’ by Renaissance church composers because of the unsettling dissonance created by the tritone interval.
• ‘The devil’s interval’ myth: It was thought that the b5 would illicit dark thoughts and feelings, which subsequently got it banned by the church – but there’s no evidence to support this.
• Instead, ‘the devil‘s interval’ was actually a metaphor used by Renaissance composer Johann Joseph Fux.
• He described the interval as simply “hard to sing” and so should largely be avoided when composing for voice.

The b5th note was always regarded as a strong ingredient when creating music. Treat it with care and it’ll sound more impactful when used in the right context.  

Finding the scale on the fretboard

The best way to navigate your way around the blues scale is to first have a really clear map of the minor pentatonic scale. The two scales are interchangeable – you can always return to the minor pentatonic if you get a bit lost.

Below, you’ll see a fretboard diagram of the minor pentatonic scale for reference.

The blues scale is simply about adding the b5th tension into the minor pentatonic.

Here’s a fretboard diagram of the blues scale:

Want more information on the minor pentatonic? Check out our jam-packed pentatonic article here!