From the December 2018 issue of Acoustic Guitar | BY GRETCHEN MENN
You are stuck in one pentatonic scale shape, and anything too far up or down the neck from that familiar shape is uncertain territory.
Use an understanding of theory combined with your fretboard knowledge to conceptualize pentatonic scales, and then map them out across the neck.
The pentatonic scale is everywhere. Its characteristic sound is useful in a wide variety of genres. Yet one particular shape of the pentatonic is far and away the favorite among guitar players. You know the one. You could write an entire course based around classic riffs, lines, and solos derived from the single shape shown in Figure 1. This lesson isn’t to bash this comfort zone for so many of us, but rather to encourage a little exploration and a more balanced pentatonic vocabulary.
If you’ve never played a pentatonic scale and have no idea what I’m talking about, fear not. As in all the lessons in this series, you’ll build your way up from the essential theoretical fundamentals and then apply them to the guitar. If you’ve been following these lessons, the work you’ve done on major and minor scales will serve you well here.
LEARN THE THEORY
As the name implies, the pentatonic scale is made up of five notes—penta (five) tonic (tone/note). There are both major and minor pentatonic forms. We have been using the major scale as a point of reference for deriving other scales, and that’s again where we will start. Remember, the formula for the major scale is 1 2 3 4 5 6 7 (8) or W W H W W W H. To build a major pentatonic, omit scale degrees 4 and 7: 1 2 3 5 6 (8). To build a minor pentatonic scale, leave out scale degrees 2 and 6, and use the minor third and minor seventh (commonly referred to as b3 and b7). So the construction of the minor pentatonic scale is 1 b3 4 5 b7 (8).
You may have noticed that deleting these scale degrees also does away with half steps, or minor seconds (e.g., from E to F, B to C, etc.). The absence of this most tense interval helps give the pentatonic scale its characteristic sound. You’re left with whole steps and minor thirds (the distance of a whole step plus a half step). The formula for the major pentatonic scale is W W m3 W m3 and that for the minor pentatonic is m3 W W m3 W.
TRANSFER TO THE FRETBOARD
Let’s apply all that. Pick a key—start with C major. Write it down somewhere, both the notes and scale degrees, as in Example 1a. Delete degrees 4 and 7 (Example 1b) to build the C major pentatonic scale (Example 1c).
Now look for the scale on the fretboard. Find C on the low E string. Stay in one position and work your way up, finding all the notes of the C major pentatonic until you hit the highest note that is part of the scale on the high E string. The end result should look like what’s depicted in Example 2. As you play, be mindful both of which note you’re playing (E, G, etc.), as well as its relation to C (the third, fifth, etc.). Once you’re solidly oriented, you can memorize the scale shape, but don’t discard the theory that got you there. You’ll also find that the pentatonic scales all fit nicely into two-note-per-string patterns.
MOVE TO THE MINOR
Now try the C minor pentatonic scale using the same steps. As shown in Example 3a, first write out the C natural minor scale, then delete the second and sixth degrees (Example 3b) to arrive at the minor pentatonic (Example 3c). Map out the minor pentatonic on the fretboard—see Example 4. Look familiar? It’s the go-to minor pentatonic shape. But now you know how it was built, meaning you’ll be able to form the other iterations of the same scale up and down the neck.
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CONSIDER THE RELATIVES
Remember the concept of relative keys—those sharing the same notes? Again, every major key has a relative minor, and vice versa. This concept is useful in thinking about pentatonic scales as well. C major and A minor, for instance, are relative keys. Example 5a shows the C major pentatonic scale (C D E G A C) next to the A minor pentatonic (A C D E G A) scale, and similarly, Example 5b shows G major (G A B D E F) pentatonic and E minor pentatonic (E G A B D E).
Keep in mind that while the two scales share the same pitches, they have distinct sounds, as the harmonic context changes the meaning of each pitch. Try playing the notes of C major pentatonic over a static C major chord, and then do the same thing with the same notes over an A minor chord. Hear it?
Your independent mission, should you choose to accept it—and you should!—is to go through the process of constructing and then connecting the major and minor pentatonic scales across the fretboard, just as you did with major and minor scales. You have a head start, as you tackled two of the five scale forms here. It might have occurred to you to just play the major and minor scales you already know, leaving out scale degrees 4 and 7 for the major pentatonic scale and 2 and 6 for the minor pentatonic scale. Go right ahead. And you may notice in doing so that the scale also takes on its own form and character. I recommend being able to see the pentatonic scales independently, as well as in relation to the full major and minor scales. As I’ve said before, the best way to have good orientation is to embrace and overcome disorientation.
This article originally appeared in the December 2018 issue of Acoustic Guitar magazine.