Blues Guitar Institute

Interval Theory Basics

Ever heard something like this?

“Play the major 6th, then resolve back to the root.”

If you’re thinking, “What the heck does that mean?” spend a little time with interval theory and it will all make sense.

What Are Intervals?

Simply put, an interval is the distance between two notes.  Here’s a quick video tutorial on interval theory.

Why Should I Study Interval Theory?

Well, let me first say that you don’t need to spend a year of your life studying interval theory.  It’s important, but I have found that a basic, fundamental knowledge of interval theory goes a long way.

Knowing your intervals, helps you communicate with other musicians.  You may be able to talk to other guitarists by saying, third fret, fifth string, but a piano player or horn player will look at you funny if you say that.

To me, the biggest reason to study intervals is because it is one of the most basic building blocks of music theory.  While I don’t read music or pretend to know what the heck “E double-flat major 13th sharp 11” is, this bit of theory helped me understand how scales and chords are built.

Knowing my intervals helps me focus on the musical aspect of guitar playing while at the same time, opening up the fretboard and freeing you from the “box” mentality.

In short, this will help you become a better musician.

So How Do We Use Intervals?

In order to really unlock the power of learning interval theory, we need to first give names to the intervals.

The common interval names are based on the major scale:

Interval Names:

  • Root
  • Major Second
  • Major Third
  • Perfect Fourth
  • Perfect Fifth
  • Major Sixth
  • Major Seventh

For now, forget about the “major” and “perfect” labels.  They are important, but learning basic interval theory becomes a little easier when you see the list like this:

  • Root
  • Second
  • Third
  • Fourth
  • Fifth
  • Sixth
  • Seventh

If you can count to 7, you can learn intervals!

Tied at the Hip:  Intervals and the Major Scale

As I mentioned, interval names are assigned based on each notes position in the major scale.

The key to learning and using interval theory is that each interval is referenced from the root note.  The distance between the root and these intervals never changes.  For example, a major second will always be one step up from the root.

Let’s assign interval names to each of the notes in the A major scale.

An Example in A Major

The notes for the A Major scale are:  A  B  C#  D  E  F#  G#

The A is called the root and is the reference point for the whole scale.

The next note, B is referred to as the major second and the interval (distance) from the root to the major second is two-half steps or two frets, same thing.  A half step = moving up one fret on the guitar.  To say it another way, moving up from the root note, A to the B is moving up a major second.

The C# note is four half-steps (four frets) up from the root. Being the third note in the scale, C# is called the major third.

The D note is the fourth.  Sometimes referred to as a perfect fourth or just the fourth.  The fourth is up five half-steps (five frets) from the root.

E is the perfect fifth, the fifth note in the scale and is seven half-steps (seven frets) away from the root.

F# is the major sixth the sixth note of the major scale  and is nine half-steps (nine frets) up from the root.

G# is the major seventh, the seventh note of the scale and eleven half-steps (eleven frets) up from the root.

Move this to Any Key

You can take the information from the a major scale and move everything to a different key.  Just start with your root and count up the correct number of  half-steps the interval you are looking for.  For example, if you want to know the 5th of c, count up seven half-steps and you will be at G.

Now, Just Practice

With a little practice and time devoted to learning interval theory, you will start to notice your fretboard making a little more sense.

Here’s a great resource for you to hear what the intervals sound like, just click here.

Now if someone asks you to play the major sixth followed by the root in the key of E, you would know exactly what to do!

When you are ready, there are two ways I can help you:

Back Porch Blues Course:  A proven system to fingerpicking the blues.  This step-by-step course guides you through building fundamental fingerpicking skills.  Plus, you’ll learn three levels of a delta blues style performance study to put your new skills into action.

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