Pentatonic scales

This article uses Fretspace to explore pentatonic scales.

The Major and Minor Pentatonic scales are a basic tool that guitarists use to improvise (or compose) solos. They are also a starting point from which we can explore more complex scales.

The first scale that most guitarists learn is the Minor Pentatonic scale. There are five shapes that are commonly used:

A Minor PentatonicA Minor Pentatonic (second position)A Minor Pentatonic (third position)A Minor Pentatonic (fourth position)A Minor Pentatonic (fifth position)

To see these shapes in Fretspace, display the scale picker and choose A Minor Pentatonic from the Scale/Arpeggio popups and 2 Notes Per String from the Shape popup. (Minor Pentatonic is in the Major Pentatonic submenu because the Minor Pentatonic scale is a mode of the Major Pentatonic scale: it has the same notes but starts from a different root.)

The first of these shapes is commonly known as the first-position Minor Pentatonic: “first position” in this context means that the shape begins with the root of the scale (the first note is A). This is usually the first scale shape that guitarists learn. The other four shapes can be regarded as inversions of this shape: if you use Fretspace to invert the first shape, it will create the second shape, which is known as the second-position Minor Pentatonic, and if you continue to invert this shape you will arrive at the three remaining shapes, known (logically) as third-position, fourth-position, and fifth-position Minor Pentatonic shapes.

The first shape is easy to learn. The sixth string has two notes that are separated by an interval of three semitones, the following three strings have two notes that are separated by an interval of one whole tone, and the second string has two notes that are separated by an interval of three semitones. The first string repeats the same notes that are on the sixth string. What makes this shape particularly easy is the fact that the first note on each string begins at the same fret.

This pattern is repeated in the other shapes: three adjacent pairs of strings have two notes separated by a tone, and two adjacent pairs of strings have notes that are separated by three semitones. Another way that you can generate the other shapes from a first-position shape is to shift each pair of dots onto the next string and copy the last pair of dots onto the string you started from. You can do this in Fretspace using the Rotate Dots command. If you use Rotate Dots Right you will end up with the following shapes:

A Minor PentatonicD Minor Pentatonic (fourth position)G Minor Pentatonic (second position)C Minor Pentatonic (fifth position)F Minor Pentatonic (third position)

Here, the first-position shape is followed by the fourth-position shape, and the remaining shapes are the second-position, fifth-position, and third-position shapes. The first-position shape is probably the most commonly used shape, and the fourth-position shape (the next shape after it in this case) is the next most commonly used shape. If you play lead guitar you should know all these shapes, but the first-position and fourth-position shapes are the shapes that you should start with.

I mentioned earlier that the Minor Pentatonic scale is a mode of the Major Pentatonic scale. In music theory, modes are scales that share the same notes but start from a different root. If you prefer, you could say that the Major Pentatonic is a mode of the Minor Pentatonic, or that they are modes of each other. The A Minor Pentatonic scale has the same notes as the C Major Pentatonic scale, but the roots are different:

A Minor PentatonicC Major Pentatonic (fifth position)

Once you know the five basic shapes of the A Minor Pentatonic scale, you also know the five basic shapes of the C Major Pentatonic scale:

C Major Pentatonic (first position)C Major Pentatonic (second position)C Major Pentatonic (third position)C Major Pentatonic (fourth position)C Major Pentatonic (fifth position)

Any Minor Pentatonic scale has the same notes as a Major Pentatonic scale whose root is a minor third (three frets) higher. Because the root is different, a first-position Major Pentatonic shape (the first of the five shapes shown above) corresponds to a second-position Minor Pentatonic shape.

Pentatonic scales and chord tones

It’s helpful to see that scales and chords are related to each other, and some guitarists use the CAGED system to do this. If you look at a third-position Major Pentatonic shape, you can see that it contains a pattern of notes that looks like an open C shape:

C Major Pentatonic (third position)C

In the CAGED system this shape might be referred to as the “C-shape pentatonic”. Whether you adopt this system of labelling shapes, it is definitely helpful to be able to associate scale shapes with related chord shapes, minor as well as major. Here are the five major and minor pentatonic shapes and their related major and minor chords:

C Major Pentatonic (fifth position)CA Minor PentatonicAmAm7
C Major Pentatonic (first position)CA Minor Pentatonic (second position)AmAm7

C Major Pentatonic (second position)CA Minor Pentatonic (third position)AmAm7/G

C Major Pentatonic (third position)CA Minor Pentatonic (fourth position)AmAm7

C Major Pentatonic (fourth position)CA Minor Pentatonic (fifth position)AmAm7/C

Note that the chord shape that resembles an open C is followed in the next line by a chord shape that resembles an open A. Returning to the top of the chart, we have a chord shape that looks like an open G followed by a chord shape that looks like an open E and a chord shape that looks like an open D: hence CAGED. (These are actually bar chords rather than open chords, but they are the barred equivalents of open chords.)

The major and minor pentatonic scales can be regarded as simplified major and minor scales, which have two extra notes. So why use pentatonic scales when we can use full scales by learning two extra notes? One answer is because they’re easy to play: you can actually play all these scales with just two fingers, and many blues guitarists do just that, using the first and third fingers of their fretting hand.

A more interesting answer can be found by looking at the intervals that these scales use. The Major Pentatonic scale has five intervals (starting from the root) which are: major second, major second, minor third, major second,  and minor third. The only intervals which occur between successive notes are a major second (two semitones) and a minor third (three semitones). By contrast, the intervals in a full Major scale are: major second, major second, minor second, major second, major second, major second, and minor second. Here the only intervals that are used are major second (two semitones) and minor second (one semitone). So one way to look at the Major Pentatonic scale is to see it as a Major scale from which semitone intervals have been removed: in each place where the Major scale has a major second (two semitones) followed or preceded by a minor second (one semitone) the Major Pentatonic scale replaces it with a minor third (three semitones).

What this means is that the Major Pentatonic scale is a less dissonant scale than the full Major scale. If you play a C Major Pentatonic scale with a C major chord, you’re less likely to play a wrong note than if you play a C Major scale with a C major chord. In jazz scale/chord theory, the fourth note of the major scale is considered to be an “avoid” note when it is played against a C major chord (it clashes with the third degree of the chord). The Major Pentatonic scale helpfully omits it.

A good way to use the Major Pentatonic scale in soloing is to choose a scale that starts from the same root as the chord you are playing against: if you do this you can play instrumental lines that fit with the accompanying chords. Guitar melodies sound more melodic if they emphasize chord tones, as happens with natural song melodies. Playing a Major Pentatonic scale against a major chord with the same root will do this, because it contains the same notes as a major chord from the same root (root, third, and fifth) plus two additional notes: the sixth and the ninth. In fact, the Major Pentatonic scale can also be regarded as a 6/9 arpeggio: a C Major Pentatonic scale contains the same notes as a C6/9 chord.

In the same way that you can use a Major Pentatonic scale over any major chord with the same root, you can use a Minor Pentatonic scale over any minor chord with the same root. Just as the C Major Pentatonic can be regarded as a C6/9 arpeggio, the A Minor Pentatonic can be regarded as an Am7/11 arpeggio: it contains the notes of an Am7 chord, plus the 11th degree of this chord (which is the same as the fourth degree).

It’s also interesting that the G Major Pentatonic scale contains the same notes as standard guitar tuning: GABDE in the scale corresponds to EADGBE in standard guitar tuning. This is actually a consequence of the fact that a guitar in standard tuning is tuned in fourths. Ignoring the top string (which has the same note as the bottom string) we have EADGB, where each successive note is a fourth higher than the previous string, except for B, which is a fourth lower than the first string (ignoring pitch differences). Any instrument that has five differently tuned strings that are a fourth apart will have the notes of a Major Pentatonic scale on its open strings. That’s also the case with instruments that are tuned in fifths, such as a guitar in NST tuning, where CGDAEG contains the notes of a C Major Pentatonic scale. Fifths and fourths are fundamental to musical harmony: the next harmonic after the octave harmonic is a fifth, and the next harmonic after that is a fourth. Much of music harmony is based around the cycle of fifths: chords tend to progress to chords that are a fifth higher (or a fourth lower, since an inverted fifth is a fourth). Pentatonic scales are also based on this cycle.

Pentatonic scales and keys

As well as matching pentatonic scales to their accompanying chords (e.g. playing C Major Pentatonic over a C major chord, or D Minor Pentatonic over a D minor chord) it’s also possible to match scales to key signatures and use a single pentatonic scale over any chord in the same key (e.g. playing C Major Pentatonic over any chord that is in the key of C). This is how blues soloing commonly works: for any blues song that is in the key of A (major or minor) you can simply play the A Minor Pentatonic scale over every chord. This actually creates an interesting set of tensions, especially when the blues song uses major chords rather than minor chords.

If we play an A Minor Pentatonic over an A7 chord (in an A major blues progression), the minor pentatonic scale (ACDEG) contains the root, fifth, and flattened seventh notes (AEG) of the A7 chord (AC#EG) along with a fourth and a flattened third (D and C). The flattened third (C) clashes with the major third of the chord (C#) and the flattened seventh note (G) matches the flattened seventh of the chord but clashes with the major seventh (G#) that would otherwise be expected: the seventh degree of an A Major scale is G sharp rather than G natural. These flattened notes are characteristic of blues melodies. It’s also common to sharpen flattened notes, so that they are replaced by their non-blues equivalents (major third or major seventh) or so that they are halfway between the two. When playing a blues solo in A, it’s common to bend C notes so that they are halfway between C and C#, and the same can be done with G notes.

The other chords in an A major blues progression are normally D7 (the IV chord) and E7 (the V chord). Playing an A Minor Pentatonic scale over a D7 chord (DF#AC) gives us the root, fifth, and flattened seventh (DAC) of this chord, along with a second (E) and fourth (G). Playing an A Minor Pentatonic scale over an E7 chord (EG#BD) gives us the root (E) and flattened seventh (D) of this chord along with a flattened third (G), fourth (A), and augmented fifth (C). In summary, a Minor Pentatonic scale which matches the key of a blues progression contains the root and flattened seventh notes of all three chords in a standard blues progression, along with the flattened third of two of these chords (the I and V chords), and the fifth note of two chords (the I and IV chords). The V chord lacks a fifth but contains a (more dissonant) augmented fifth, which anticipates the flattened third of the I chord or the flattened seventh of the IV chord.

Diagonal pentatonic shapes

In addition to the five standard box shapes of the Major Pentatonic and Minor Pentatonic scales, there is another shape that is useful. In Fretspace, select C Major Pentatonic from the scale picker, and choose Diagonal (rather than Box or 2 Note Per String) from the Shape popup. You will see the following two shapes:

C Major Pentatonic (second diagonal shape)C Major Pentatonic (first diagonal shape)

The useful characteristic of these shapes is that they stretch diagonally across the fretboard, allowing you to move between different box positions along the neck. They are also extremely simple. To play these shapes, all you have to do is to find the root note (C in this case) and play this note followed by two notes that are one whole tone (two frets) apart from the previous note. The normal way of playing these notes is to use slides: play the first note with your first finger, and play the second note with your third finger, then slide your third finger up two frets and play the third note. Instead of sliding between the second and third notes, you can also slide your first finger between the first and second notes. By the time you get to the third note, your first finger is two frets higher than where it started from. Move it across to the same fret on the next string (or one fret higher if the next string is the B string) and the note on that string is the fifth degree of the scale (G). Play that note followed by a note that is two frets higher. Then move your first finger across to the same fret on the next string (or one fret higher on the B string) and start again. That’s all you have to do: you can just keep going until you run out of strings or fretboard. The same pattern (R 2 3 followed by 5 6) keeps repeating. You can play down the scale by reversing this sequence: start on the sixth degree (A) and play this followed by a note that is two frets lower, then switch to the same fret on the next string (or one fret lower if you’re moving from the B string) and play that note (the third degree: E) followed by two notes that are two frets lower (sliding between the third and second or second and root notes).

You can obviously use the same shape to play an A Minor Pentatonic scale. In this case the pattern starts on the third degree of the scale (C) when ascending  and on the root of the scale (A) when descending.

Another benefit of using this shape is that it helps you to learn where notes are on the fretboard. You can use it to play major and minor pentatonic scales in any key, so long as you can find the root note of that key. Practice starting from a root note on any string: C (or any other root) on the sixth string, C on the fifth string, C on the fourth string, C on the third string, C on the second string. Descending, start from A (or any other note) on the first string, A on the second string, and so on. Then try starting from the fifth (G or any other fifth) and so on. If you keep doing this you will soon learn where to find notes on any string. Most guitarists learn the names of notes on the bottom two strings when they start learning bar chords with roots on these strings, but they often struggle with the names of notes on the fourth, third, and second strings. (The first string is easy because it is the same as the sixth string.)

Dominant and Dorian Pentatonic scales

There is another pentatonic scale that is less well known. If we take a C Major Pentatonic scale and replace the sixth (A) with a flattened seventh (Bb) we have a pentatonic scale that contains the four notes of a dominant seventh chord along with a ninth, i.e. the five notes of a dominant ninth chord. This makes it a good scale to use with any dominant chord (especially dominant seventh and dominant ninth chords). This scale is known as the Dominant Pentatonic scale. It has the following basic shapes:

C Dominant Pentatonic (first position)C Dominant Pentatonic (second position)C Dominant Pentatonic (third position)C Dominant Pentatonic (fourth position)C Dominant Pentatonic (fifth position)

There is also a minor mode of this scale, which Fretspace refers to as the Dorian Pentatonic, because it contains notes that are found in the Dorian mode of the Major scale, including a minor third and major sixth. A Dorian Pentatonic scale is the same as a Dominant Pentatonic that starts from its fourth note (or fifth degree): G Dorian Pentatonic is the same as C Dominant Pentatonic. Here are the five basic shapes:

G Dorian Pentatonic (first position)G Dorian Pentatonic (second position)G Dorian Pentatonic (third position)G Dorian Pentatonic (fourth position)G Dorian Pentatonic (fifth position)

As you can see, a first-position Dorian Pentatonic scale is the same shape as a fourth-position Dominant Pentatonic scale.

Another way to look at the Dorian Pentatonic scale is to see that it is similar to a Minor Pentatonic scale in which the minor seventh has been replaced by a sixth. Here is an A Dorian Pentatonic scale next to an A Minor Pentatonic scale:

A Dorian Pentatonic (first position)A Minor Pentatonic

Blues guitarists (such as Robben Ford) sometimes use the Dorian Pentatonic scale to provide a more jazzy alternative to the Minor Pentatonic scale.

Sus6/9 Pentatonic

Since there are five notes in a pentatonic scale, there five possible modes of the Major Pentatonic scale and of the Dominant Pentatonic scale. Some of these modes are fairly exotic, but there is one other mode of the Major Pentatonic scale that is worth looking at. The Sus6/9 Pentatonic is equivalent to a Major Pentatonic scale that starts from its fourth note (sixth degree). Here are the five basic shapes:

G Sus6/9 Pentatonic (first position)G Sus6/9 Pentatonic (second position)G Sus6/9 Pentatonic (third position)G Sus6/9 Pentatonic (fourth position)G Sus6/9 Pentatonic (fifth position)

Of course, these are the same as the shapes of the Major Pentatonic scale, so there is no need to learn them separately. What makes this shape interesting is that the third-position shape is similar to a blues shape that B. B. King popularized, and which has come to be known as the B. B. King box. If we move this shape up by two semitones, we can compare it to the B. B. King blues shape in its most basic form:

A Sus6/9 Pentatonic (third position)A Blues Box

We will look at this shape in more depth in the following article (on Blues scales).

Pentatonic scales and extended chords

Despite (or because of) their simplicity, there are some advanced ways of using pentatonic scales with extended chords—chords that contain extensions such as a sixth, seventh, ninth, eleventh, or thirteenth. Most chords are formed by stacking thirds. A simple triad normally contains a root note followed by two thirds (C E G for a C major triad). Extended chords can be created by stacking additional thirds on top of a triad. For example, a major seventh chord is the same as a major chord with an additional note that is a third higher than the previous note: C E G B for Cmaj7. The interesting thing about this is that if we drop the bottom note of this chord we have another triad that is a simple Em chord. What this means is that any time we need to play Cmaj7, we can substitute it with an Em chord—so long as someone else is playing the bass note. We can apply the same principle to scales: any time we are playing against a Cmaj7 chord, we can use an E Minor Pentatonic scale to do this. For a more jazzy sound, we could also use a B Minor Pentatonic scale, which contains the 3, 7, 9, #11, and 13 degrees of a Cmaj13#11 chord. Another example: D13 (which is essentially a more jazzy version of D7) contains the notes D F# A C E G B. Since this chord also ends with an Em triad, we could play an E Minor Pentatonic over it. For more information on using pentatonic scales in this way, see Pentatonic Khancepts by Steve Khan.

Using an A Minor Pentatonic scale over a D7 chord (as in blues solos) is actually another example of this. A D9 chord contains the following notes: D F# A C E. The top three notes of this chord are obviously the same as an Am chord, so it makes sense that we can use an A Minor Pentatonic with any D7 or D9 chord.

Reference charts

We can use Fretspace to create a set of reference charts. Pentatonic scales can be viewed as a starting point from which to explore other types of scales, including blues scales, major and minor scales, and bebop scales, so these charts are an important foundation for later discussions. The ultimate goal is to know how to play and use any scale. Pentatonic shapes are the first shapes you should learn. If you know them already, it’s still useful to organize that knowledge in a systematic way.

Start by creating a new document. Call it “Guitar Scales”.

Major Pentatonic Chart

Name the first chart “Major Pentatonic”. Select Show Title, Show Degrees, and Color Root Notes from the Chart section of the Inspector panel. This chart will contain the shapes of the Major Pentatonic, Minor Pentatonic, and Sus6/9 Pentatonic scales, which (as we have seen) are modes of a single scale.

Major Pentatonic shapes

  1. Display the scale picker and choose C Major Pentatonic from the Scale / Arpeggio popups and 2 Notes Per String from the Shape popup.
  2. Select all the shapes except the first (which is an open-position shape) and add them to the chart.
  3. Rearrange the shapes so that the shape which begins with the colored root note is first. To do this, deselect the last three shapes, and drag the first two shapes to the end of the line.
  4. Add a break at the end of the line: select the last item and press Return.

You should now have a line of C Major Pentatonic shapes arranged according to position: first, second, third, fourth, and fifth position. The first-position shape starts with the root of the scale, the second-position shape starts with the second note, and so on.

C Major Pentatonic (first position)C Major Pentatonic (second position)C Major Pentatonic (third position)C Major Pentatonic (fourth position)C Major Pentatonic (fifth position)

Minor Pentatonic shapes

  1. Display the scale picker and choose A Minor Pentatonic.
  2. Select all the shapes except the first and add them to the chart.
  3. Drag the first shape to the end of the line so that the shape that begins with the colored root note is first.
  4. Add a break at the end of this line.

You now have a line of A Minor Pentatonic shapes starting with the first-position shape.

A Minor Pentatonic (first position)A Minor Pentatonic (second position)A Minor Pentatonic (third position)A Minor Pentatonic (fourth position)A Minor Pentatonic (second position)

Sus6/9 Pentatonic shapes

  1. Display the scale picker and choose G Sus6/9 Pentatonic (don’t confuse this with the similarly named Sus9 Pentatonic).
  2. Select all the shapes except the first and add them to the chart.
  3. Add a break at the end of the line.

You now have a line of G Sus6/9 Pentatonic shapes starting with the first-position shape.

G Sus6/9 Pentatonic (first position)G Sus6/9 Pentatonic (second position)G Sus6/9 Pentatonic (third position)G Sus6/9 Pentatonic (fourth position)G Sus6/9 Pentatonic (fifth position)

Because the Major, Minor, and Sus6/9 Pentatonic scales are modes of the same (Major Pentatonic) scale, the shapes for each scale are the same. All you need do is to learn five basic shapes and take note of which shape is the first-position shape for each scale. The Minor Pentatonic scale begins on the sixth degree of the Major scale. Since there is no fourth degree in the Major Pentatonic scale (as you can see if you have Show Degrees turned on) a first-position Minor Pentatonic shape is the same as a fifth-position Major Pentatonic shape. The Sus6/9 Pentatonic scale begins on the fifth degree of the Major scale, so a first-position Sus6/9 shape is the same as a fourth-position Major Pentatonic shape.

Dominant Pentatonic chart

Select New Chart from the Chart menu to create a new chart. Name this “Dominant Pentatonic”. Select Show Title, Show Degrees, and Color Root Notes from the Chart section of the Inspector panel. This chart will contain the shapes of the Dominant and Dorian Pentatonic scales, which (as we have seen) are modes of a single scale.

Dominant Pentatonic shapes

  1. Display the scale picker and choose C Dominant Pentatonic.
  2. Select all the shapes except the first and add them to the chart.
  3. Drag the first two shapes to the end of the line so that the shape that begins with the colored root note is first.
  4. Add a break at the end of the line.

You now have a line of C Dominant Pentatonic shapes starting with the first-position shape.

C Dominant Pentatonic (first position)C Dominant Pentatonic (first position)C Dominant Pentatonic (third position)C Dominant Pentatonic (fourth position)C Dominant Pentatonic (fifth position)

Dorian Pentatonic shapes

  1. Display the scale picker and choose G Dorian Pentatonic.
  2. Select all the shapes and add them to the chart.
  3. Add a break at the end of the line.

You now have a line of G Dorian Pentatonic shapes starting with the first-position shape.

G Dorian Pentatonic (first position)G Dorian Pentatonic (second position)G Dorian Pentatonic (third position)G Dorian Pentatonic (fourth position)G Dorian Pentatonic (fifth position)

Once again, since these are modes of the same scale, the shapes are the same: all you need do is learn five basic shapes and take note of which shape is the first-position shape for each scale. The Dorian Pentatonic scale begins on the fifth degree of the Major scale; since there is no fourth degree in the Dominant Pentatonic scale, a first-position Dorian Pentatonic scale is the same as a fourth-position Dominant Pentatonic scale.

Diagonal Pentatonic chart

Create a new chart and name it “Diagonal Pentatonic Shapes”. Select Show Title, Show Degrees, and Color Root Notes from the Chart section of the Inspector panel.

Diagonal Major Pentatonic shapes

  1. Display the scale picker and choose C Major Pentatonic from the Scale/Arpeggio popups and Diagonal from the Shape popup.
  2. Select both shapes and add them to the chart. Drag the first shape to the end of the line, so it follows the first-position shape.
  3. Add a break at the end of the line.

C Major Pentatonic (diagonal first position)C Major Pentatonic (diagonal second position)

Note that there is really only one pattern across both shapes: R, 2, 3 on one string, then 5 and 6 on the next string.. You don’t need to add Minor and Sus6/9 shapes: just start with the sixth degree (last note in the Major pattern) for the Minor Pentatonic or with the fifth degree (second to last note in the Major pattern) for the Sus6/9 Pentatonic.

Diagonal Dominant Pentatonic shapes

  1. Display the scale picker and choose C Dominant Pentatonic from the Scale/Arpeggio popups.
  2. Select both shapes and add them to the chart. Drag the first shape to the end of the line, so it follows the first-position shape.
  3. Add a break at the end of the line.

C Dominant Pentatonic (diagonal first position)C Dominant Pentatonic (diagonal second position)

Again, there is just one pattern across both shapes: R, 2, 3 on one string, then 5 and b7 on the next string. For a Dorian Pentatonic, start with the fifth degree of the Dominant Pentatonic: this is the second to last note in the Dominant pattern, and first note on string next to the string that contains the root note).

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