4 Music Theory Fundamentals - Guitar Lesson

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Guitar music theory can be quite intimidating for a lot of newer guitar players. In this lesson, I'm going to keep it really simple for you. I'm going to cover the 4 music theory fundamentals that you should know as a guitar player, so you can begin to really understand how music theory works. These fundamentals are necessary if you're interested in learning how major chords are made, how to read guitar tabs, how to read sheet music, and much more.

The Natural Musical Alphabet

The musical alphabet may seem very simple, but it's very important to cover. It is the foundation for everything you'll learn in music theory. The natural musical alphabet is simply the first 7 letters of the alphabet.

Musical Alphabet

Half-Steps & Whole-Steps

We're going to look at half-steps and whole-steps in two ways. The first way, is to look at a piano keyboard. A half step is just the distance between a key, and a key directly beside it. For a whole step, we just have to skip one note, and play the key next to it.

Piano Intervals

On the guitar, things will feel a little different. A half step is just the difference between a note, and another note one fret up or down. A whole step on the guitar is the difference between a note, and another note two frets up or down.

Guitar Intervals

Sharps, Flats, & Naturals

The notes in the natural musical alphabet can be affected by sharp, flat, and natural signs.


Natural: A natural note is just an unaltered note. It isn't a sharp or a flat. Just like the ones in the natural musical alphabet we looked at earlier.


Sharp Sign: A sharp sign raises the natural note by one half-step.

Sharp Sign

Flat Sign: A flat sign lowers the natural note by one half-step.

Flat Sign

Natural Sign: Sometimes, you'll start out by playing a note sharp or flat in a song. But later on you might see a natural sign next to a note. That just means to play it as if it wasn't sharp or flat.

Natural Sign

The BC & EF Rule

This fundamental is the most difficult to grasp. The BC & EF rule states that every note in the natural musical alphabet EXCEPT for B & C and E & F have a whole-step between them. This means that B & C and E & F only have a half-step between them.

BC & EF Rule

Another way to easily visualize this, is to look at a piano keyboard. Within an octave on the piano, you'll notice that there are two spots that have two white keys right next to each other. There is no black key between B & C and E & F, which means that there is only a half-step between them.

Piano BC & EF Rule