A few years ago, a student of mine asked what’s the most important music theory concept I should learn? My response to his question was: Learn the Number System in music.
The number system in music is a super-efficient way to describe the notes and chord changes that are being played.
Here’s some of the benefits of learning this system:
- You’ll understand music theory faster
- You’ll be able to comprehend what you’re hearing in a more streamlined way (music theory and ear training go hand-in-hand)
- You’ll be able to transpose any phrase, lick, or chord progression in any key
- You’ll be able explain music more simply
If you want to accelerate your musical growth, this is the concept you’ll want to learn.
Let’s dive in.
One thing worth naming before we go further: the number system isn’t just a theory shortcut — it’s one of the most direct routes to closing the gap between what you hear and what you can play. When you know a phrase as numbers rather than letter names, it moves from something you have to look up to something you can access instantly. That’s the shift that makes playing by ear feel less like guessing and more like reaching for something you already know is there.
TL;DR
If you’re short on time, watch my video The Number System in Music (A simple explanation for absolute beginners). In the video, I’ll breakdown this powerful system that’s widely used by professional musicians.