Guitar Scale Anatomy: Theory Explained Behind Guitar Scales

I remember that when I was first beginning guitar I was hungry to learn the chords and lead lines of popular songs. While I learned a lot from this, after awhile, it left me feeling disappointed because I didn’t really know how to create and form my own cool lead lines, solos, licks, or whatever you want to call them.

I remember it being suggested to me that I learn guitar scales up and down the guitar neck so I could learn the guitar fretboard. I was told, if you know your guitar scales you can master the guitar fretboard. Maybe you too have been suggested or heard such a suggestion. So as a hungry beginner I started practicing different scale patterns.

The Main Problem

I practiced away, but for the life of me, I couldn’t figure out how to apply these scales I was learning into a song. I was learning a ton of patterns, but didn’t know what to do with them! In hindsight, I realize that in my attempt to learn the guitar fretboard, I was only learning guitar scale patterns, and I wasn’t learning how the notes, in those patterns, function together as a cohesive whole.

Perhaps you too have tried approaching learning the guitar fretboard by learning scale patterns, but quickly found that you didn’t have a clue as to how to piece those different patterns together.  Guitar scale patterns are good, but not if you don’t understand how they function and apply!

So before we go into learning talking about any type of scale or scale pattern (pentatonic, major, minor, dorian, etc.), let’s establish an understanding for how the notes that make up a guitar scale function within a scale by looking at the theory behind guitar scales.  Now, I realize music theory can only be so exciting, but it’s extremely beneficial if you’re wanting to have a more complete understanding of the guitar fretboard.

What is a scale?

To put it simply, a scale is a group of notes (pitches) arranged in ascending and descending order. Musicians will use scales as a way to express the types of notes used in a song or use scales as a way to develop the song’s “key.”  Meaning, complete songs are written based on a particular scale.  If you can figure out the scale or “key” that the song uses, then you know the exact notes you can or cannot use to solo your own part over the song.

As you probably know, notes are expressed by letter names. The first seven letters of the alphabet are used to represent note names (A, B, C, D, E, F, G).

How does a scale work?

A scale is made up of whole steps and half steps between notes.  On the guitar, if you placed one finger on the 1st fret of the low ‘E’ string and move your finger to the 2nd fret, you’ve moved up in pitch one half step. Say you were to move your finger from the 1st fret of the low ‘E’ string up two frets to the 3rd fret.  If you did this, you would have moved up in pitch two half steps or one whole step.

If you know where the half steps or whole steps are in a particular scale, you will be able to more easily play that scale up and down the fretboard of the guitar, because you will know how many frets you need to move up or down on the string to hit the right note.

Scales that will sound most familiar to our ears will have a mixed arrangement of half steps and whole steps.  So for example, let’s play the following notes in this guitar tab on the high ‘E’ string.

e ----0--2--4--5--7--9--11--12-----
b ---------------------------------
g ---------------------------------
d ---------------------------------
a ---------------------------------
e ---------------------------------

After you’ve played that, play this:

e ----0--2--3--5--7--8--10--12-----
b ---------------------------------
g ---------------------------------
d ---------------------------------
a ---------------------------------
e ---------------------------------

The first example is an “E” major scale.  The second example is an “E” minor scale.  They are both technically “E” scales, but the arrangement of half steps and whole steps within the scale gives it a “major” or “minor” characteristic.  Do you see how the half steps and whole steps in both scales are arranged?  If not, we will dive into this in our next post.

The Next Step

Guitar Scales Explained

If this feels a little confusing and you’re not sure how to apply it, don’t worry.  This is just an intro to the fundamentals and theory behind guitar scales.  It’s important to be able to understand the principles and the theory before we try to apply this.

In fact, understanding how the notes on the guitar fretboard relate and interact with one another is one of the most important keys to learning the guitar fretboard. If you are eager to continue to learn the guitar fretboard and learn how to use scales to improvise and craft solos, I would recommend checking out Craig Basset’s Guitar Scale Mastery System. I highly recommend it.

To learn more about it, you can either click here, or I wrote a more in depth review of his method here.

If you’re ready, move on to part 2 of Guitar Scale Anatomy, and learn about the theory behind a major scale!

About Brett McQueen

Brett McQueen is a musician, songwriter, and the founder and editor of Guitar Friendly and Ukulele Tricks. Learn more about him here and follow him on Twitter at @GuitarFriendly.