Year 8 Music · Making Music — Compose and Perform · 9m read

Chords and Harmony Basics

Chords are the harmony behind a melody. With just three chords you can accompany thousands of songs.

Learning objective: Build major and minor triads and use primary chords.

By the end of this lesson you can:

• I can build a triad.
• I can tell major from minor by ear.
• I can play chords I, IV and V.

Chords are musical Lego. A single note is one Lego brick. Stack three bricks in a pattern — every second note — and you get a chord. Swap the middle brick slightly and the whole tower changes colour from bright (major) to moody (minor).

Chords and Harmony Basics

TRIADS:
• Three notes stacked in thirds: root, third, fifth.
• C major = C E G. A minor = A C E.
• Major sounds bright; minor sounds darker.

PRIMARY CHORDS IN C MAJOR:
• I = C major, IV = F major, V = G major.
• Many songs use only I, IV and V.

ACCOMPANYING:
• Strum or play chords on the beat while a melody plays.

| Chord in C major | Roman numeral | Notes | Feel |
|---|---|---|---|
| C major | I | C E G | Home, stable |
| D minor | ii | D F A | Gentle, moving |
| F major | IV | F A C | Warm, lifting |
| G major | V | G B D | Tension, wants to go home |
| A minor | vi | A C E | Sad, reflective |

Key ideas at a glance

• Stack every second note: Root, skip one, third, skip one, fifth.
• The third decides the mood: 4 semitones = major; 3 semitones = minor.
• V wants to go to I: Ending G → C sounds finished.
• Three chords go a long way: I, IV and V accompany thousands of songs.

Worked example (Easy)

Build the G major triad.

1. Root. G
2. Third. B
3. Fifth. D

Answer: G B D.

Worked example (Medium)

Is the triad D–F–A major or minor?

1. Count root to third. D to F = 3 semitones.
2. Decide. 3 semitones = minor third.

Answer: D minor.

Common mistakes

• Using the wrong third The third decides major or minor. Fix: Count semitones: 4 for major, 3 for minor.
• Building chords from neighbouring notes C–D–E is a cluster, not a triad. Fix: Skip a note between each chord tone.

Why do major chords sound "happy"?

There is no single scientific answer, but two ideas help.

Physics: the notes in a major triad line up neatly with the natural overtones that vibrate above any note, so they blend smoothly.

Culture: in Western music we hear major chords at celebrations and minor chords in sad scenes from childhood, so we learn the association. Music from other cultures doesn't always link major with happy — context shapes meaning.

Practice questions

1. Chord V in C major is:

   1. F
   2. G
   3. A minor
   4. E

   (1 marks)

2. What notes are in a triad?

   (2 marks)

3. Chord IV in C major is:

   1. G major
   2. F major
   3. A minor
   4. D minor

   (1 marks)

4. Which chord creates the strongest pull to finish on C?

   1. F
   2. Am
   3. G
   4. Dm

   (1 marks)

5. Write the notes of A minor and C major and explain how they are related.

   (2 marks)

Summary

• Triads: root, third, fifth.
• Major bright, minor darker.
• I, IV, V are primary chords.
• The third decides major or minor.