What is music theory and why is it important?

Hi fans of the One Minute Music Lesson,

It took me 20 years to learn the importance of music theory. Today I want to teach you what music theory is and why it is important, and save you 20 years of trial and effort in the process.

Let’s begin with a definition. Music theory is the mathematical language of music. You may not realize this but any piece of music you have ever heard can be thought of and discussed in terms of its mathematical proportions and relationships between every single note in the piece.

Music theory encompasses a huge amount of information and explanations of the how’s and why’s of the rules and conventions of music. People have studied music theory since the beginning of recorded history. Millions of people have already though long and hard about why does this note sound good with this one but not with the other. The process of how to create a chord progression has been established for over 300 years. If you learn music theory you will know this information and thus not have to search for the answers to these questions through thousands of hours of trial and error.

By understanding music theory you can critically analyze music that has already been written by composers and songwriters which will allow you to absorb the tricks and techniques of any song by simple looking at the mathematical data written in the sheet music. This hidden data will be in plain sight once you understand how to recognize chords, scales and voice-leading.

By knowing how music theory works you are literally becoming fluent in a language that is shared by musicians since the times of the ancient greeks. This language allows us to stop repeating the same mistakes over and over in our instrument playing and practicing as well as composition, improvisation and soloing. Knowing this language can save you weeks of practice time on new pieces allowing you to practice smart, not hard.

Here’s a fact you may not know: There are only 12 pitches in music, but there are 24,576 possible combinations of notes to form any single harmony. By understanding music theory you reduce this number substantially because you learn how to create any of these combinations from memory and how to limit them to just the few that work in conjunction with each other in a pleasing way to your ear.

Over the course of the next month I will be teaching introductory concepts of music theory and ear training, the flip-side of the music theory coin. Some of this material will be on my free video lesson series Understanding Music Theory on my free video lesson page. More of this material will be sent exclusively to subscribers of my free newsletter.

If you are interested in learning how to use the power of music theory in your instrument playing and music writing I encourage you to follow along with the announcements on my newsletter about my upcoming members-only music academy.

Until next time: Practice Smart – Not Hard,

Leon Harrell

Where to go next:

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  • Paul Mumford


    I was just searching the internet to see if anybody else had the figure 24,576 as the total number of modes derived from the total number of scales (4095) and I see you have the figure 24,765 on your page to represent the “possible combinations of notes to form any single harmony”. I am very interested in how you arrived at this number, and what exactly you mean by the phrase “possible combinations of notes to form any single harmony”. Would you have the time to explain this by any chance?

    Many thanks,


    • leonharrell

      Hi Paul,

      It’s been a while since I wrote this post with the figure 24,576. I’m pretty sure I got this number from the Joseph Schillinger Book “The Schillinger System of Musical Composition” but now I don’t quite remember. I will do my best to find my source and post a comment back here when I do.

      As for the phrase “possible combinations of notes to form any single harmony” I intend to mean any combination of two or more notes up to twelve with no repetitions of combinations.

      I will look into this a get back to you as soon as possible.

      Thanks your commenting,

      Leon Harrell

      PS. May I ask what got you interested in find that information?