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Field guide · Eight short chapters

Guitar music theory for beginners

Music theory, from the fretboard up. Theory is just names for the sounds your hands already make. Each chapter is short, and every example can be played.

01Notes

Note names: seven letters, twelve sounds

The musical alphabet runs A to G and then starts again — with five extra notes hiding in the gaps.

Music uses seven letter names. Between most neighbouring letters sits one more note, so an holds twelve different pitches, each a (one semitone) from the next. Two half steps make a .

Raise a note by a half step and it gets a sharp (♯); lower it and it gets a flat (♭). So C♯ and D♭ are the same sound with two names — spellings. Which one you write depends on the key you are in. Two pairs of letters have nothing between them: E–F and B–C.

12 notes · 7 letter names · tap to hear

No black key between E–F and B–C: those are natural half steps.

02The fretboard

The fretboard: every fret is a half step

Six strings, tuned E A D G B E from low to high. Learn one string and you can find every note.

Each raises a string by exactly one , so the 12th fret is the same note as the open string, an higher — that is why the inlay dots double there and the pattern repeats.

In standard tuning the 5th fret of each string matches the next open string, except on the G string, where the 4th fret gives you B. Start by learning the natural notes on the low E and A strings: they name the of almost every you will play.

EADGBE01357912EFGABCDEABCDEFGADEFGABCDGABCDEFGBCDEFGABEFGABCDE
Learn to read it as guitar tab

03Intervals

Intervals: the distance between two notes

Counted in , named by letters. Every chord and scale is a recipe of .

C up to E is a third because it spans three letter names (C, D, E). Its quality — major, minor or perfect — comes from the exact number of . Unisons, fourths, fifths and are perfect; seconds, thirds, sixths and sevenths come in major and minor versions, the minor one a half step smaller.

7 half steps · 5

Perfect fifth

A → E

Strong, stable — the power chord

Hear it: Twinkle Twinkle Little Star

EADGBE01357912AAAAAAAEEEEEEEE
  • P1Perfect unison0 half steps · degree 1 · Identical pitch
  • m2Minor second1 half step · degree ♭2 · Tense, crunchy
  • M2Major second2 half steps · degree 2 · Open, stepwise
  • m3Minor third3 half steps · degree ♭3 · Dark, sad
  • M3Major third4 half steps · degree 3 · Bright, happy
  • P4Perfect fourth5 half steps · degree 4 · Open, suspended
  • TTTritone6 half steps · degree ♯4 / ♭5 · Unstable, restless
  • P5Perfect fifth7 half steps · degree 5 · Strong, stable — the power chord
  • m6Minor sixth8 half steps · degree ♭6 · Bittersweet
  • M6Major sixth9 half steps · degree 6 · Sweet, warm
  • m7Minor seventh10 half steps · degree ♭7 · Bluesy, wants to move
  • M7Major seventh11 half steps · degree 7 · Dreamy, yearning
  • P8Octave12 half steps · degree 8 · Same note, higher

04Scales

Scales: a ladder of whole and half steps

The major scale is one fixed pattern — W W H W W W H — started on any note.

Start the major-scale pattern on C and you only touch natural notes. Start it anywhere else and the pattern forces sharps or flats into the scale — which is exactly what a records.

Every major scale has a that starts on its 6th note: A uses the same seven notes as C major. And guitarists live on scales: drop the 4th and 7th from major (or the 2nd and 6th from minor) and you are left with five notes that are very hard to make sound wrong.

5 notes · W+H – W – W – W+H – W

A minor pentatonic

The first scale most guitarists learn: the backbone of blues and rock soloing.

  1. A1
  2. C♭3
  3. D4
  4. E5
  5. G♭7
EADGBE0135791215AAAAAAAAEGCDEGCDEGCDEGCDEGCDEGCDEGCDEGCDEG
  • Root
  • Scale tone
See every scale position with CAGED

05Chords

Chords: stacking thirds

, third, fifth. The third decides major or minor; the fifth holds it together.

A stacks two thirds on a . A major third on the bottom (4 ) sounds bright; a minor third (3) sounds darker. Stack one more third and you get a — the sound of blues ( 7) and jazz (major and minor 7).

On guitar those three or four notes get doubled across six strings: an open C chord plays C–E–G–C–E. Movable shapes let one fingering play every root — slide it to a new and the chord name follows the root note on the low E or A string.

M3 + m3

major

1 3 5

Bright, settled

m3 + M3

minor

1 ♭3 5

Darker, reflective

m3 + m3

diminished

1 ♭3 ♭5

Tense, unstable

M3 + M3

augmented

1 3 ♯5

Dreamy, unresolved

Stacked from the root

C

C major

C1
E3
G5

Half steps from the root: 0 · 4 · 7

06Harmony in a key

Chords in a key: seven chords that belong together

Build a on every note of a major scale and the qualities always land in the same order.

Using only notes from the scale, the chords come out major, minor, minor, major, major, minor, — in every major key. name them by (upper case for major, lower case for minor), so a progression written as I–IV–V works in any key.

The chords fall into three families. chords feel like home. chords move away from home and lead to the . Dominant chords build tension that wants to resolve back home — the pull of V to I is the strongest move in Western harmony.

See the chords in every key, or read why some chords in a key are major and some minor.

Diatonic triads in C major

  1. IC
  2. iiDm
  3. iiiEm
  4. IVF
  5. VG
  6. viAm
  7. vii°B°
TonicPredominantDominantHear them in every key

07Circle of fifths

The circle of fifths: a map of every key

Each step clockwise goes up a fifth and adds a sharp or drops a flat. Each step anticlockwise does the opposite.

Line the keys up so each is a perfect fifth above the last and they close into a circle. Neighbouring keys share six of their seven notes, which is why songs move between them so easily. Each major key's relative minor sits just inside it.

Better still, the six most useful chords of any key — I, IV, V on the outside, vi, ii, iii on the inside — are the key and its two neighbours. Sharps are added in the order F C G D A E B; flats run the same list backwards, B E A D G C F.

Open the simulation

Click any key to explore it.

08Rhythm & meter

Rhythm: counting time

Pitch is half of music. The other half is when the notes happen.

A has two numbers: the top says how many beats are in each bar, the bottom says which note value gets one beat. In 4/4 you count “1 2 3 4”; strum eighth notes and it becomes “1 & 2 & 3 & 4 &” — down on the numbers, up on the “ands”.

Note values in 4/4
NoteBeatsCount
Whole note41 – 2 – 3 – 4
Half note21 – 2
Quarter note11
Eighth note½1 &
Sixteenth note¼1 e & a
  • 4/4Four steady beats. Most rock, pop, blues and funk.1 2 3 4
  • 3/4Three beats, a lilting waltz feel.1 2 3
  • 6/8Two big beats, each split in three. Rolling ballads like House of the Rising Sun.1 2 3 4 5 6
  • 12/8Four big beats of three — the slow blues shuffle.1 & a 2 & a 3 & a 4 & a
Practise with the metronome