# Why guitarists avoid theory Most guitarists wear their lack of theory knowledge like a badge of honor. They say things like, *"I just play by feel, man. Theory ruins the soul of the music."* Theory gives names to sounds and relationships you may already recognise by ear. Understanding those names makes the fretboard easier to navigate. ## The musical alphabet Forget complex sheet music for a moment. Western music is built on just 7 letters: **A, B, C, D, E, F, G**. Between most of these letters, we have sharps (#) and flats (♭). Think of them as the half-steps in between. The golden rule to remember: **There is no sharp/flat between B & C, and E & F.** If you can count from A to G and remember that rule, you can navigate any string on the guitar. ## Intervals: the distance between notes Chords and scales are not random shapes to memorise. They are built from **intervals**, which describe the distance between two notes. - **Minor 3rd (3 frets):** Dark, sad, brooding. - **Major 3rd (4 frets):** Bright, happy, triumphant. - **Perfect 5th (7 frets):** Powerful, open, unresolved (the classic Power Chord). Seeing chords as stacked intervals helps you find the same relationships in other parts of the neck.

Finding the perfect fifth

If you know where your root note is, its perfect fifth is usually one string down and two frets over. This repeated relationship makes intervals easier to visualise on the guitar.

## The circle of fifths The circle of fifths looks complicated at first, but it gives you a quick view of related keys and chords. - **Adjacent keys share chords:** If you are playing a song in G Major, look at the keys right next to G on the circle (C and D). Those are your primary chords. - **Borrowing emotion:** Want to make a happy progression sound slightly melancholic? Borrow the relative minor from the inner ring of the circle. ## The Nashville Number System (1-4-5) Professional session musicians don't shout chord names at each other. They use numbers. If someone says "Play a 1-4-5 in C," they mean: - **1 (I):** C Major - **4 (IV):** F Major - **5 (V):** G Major The 1-4-5 progression appears throughout rock, blues and pop, including music by The Beatles, AC/DC and Ed Sheeran. The number system also helps you transpose the same progression into another key. ## Apply the ideas to a song Choose one song you know and identify its notes, intervals or chord numbers on the fretboard.

Want help applying theory?

We teach theory through the songs you are already learning, so each idea has a sound and a use.

Learn the fretboard

Want help with your playing?