Harmonia.
Level 1 · Lesson 2

Chords

Build a triad, enrich with a seventh, master inversions.

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Pause Culture · Les Accords
J.S. Bach (1685–1750)

It is said that Bach would get up at night to resolve on the piano a tritone left unresolved by his sons. The dissonant chord created such tension in his ear that he could not slee…

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À retenir : A chord is not merely a stack of notes — it is a force seeking rest.

Building a triad

A chord is born from a simple idea: stacking thirds. Start from a root, move up by a third, then another. Two stacked thirds produce three pitches — a triad. What differentiates the four types is the size of each third.

Root
Chord type
CC – E – Gstable
C
root
Tierce majeure (4 demi-tons)
E
third
Tierce mineure (3 demi-tons)
G
fifth
Fifth: juste (7 demi-tons)

La triade la plus lumineuse. Sa quinte juste lui donne une assise solide — couleur brillante, affirmée, ouverte.

Do3MiFaSolLaSiDo4MiFaSolLaSiDo5

The 4 triad types

TypeStructure (thirds)FifthStabilityExample (on C)
MajorTierce majeure (4 demi-tons)
+ Tierce mineure (3 demi-tons)
juste (7 demi-tons)stableC = C–E–G
MinorTierce mineure (3 demi-tons)
+ Tierce majeure (4 demi-tons)
juste (7 demi-tons)stableCm = C–Eb–G
DiminishedTierce mineure (3 demi-tons)
+ Tierce mineure (3 demi-tons)
diminuée (6 demi-tons)unstableCdim = C–Eb–Gb
AugmentedTierce majeure (4 demi-tons)
+ Tierce majeure (4 demi-tons)
augmentée (8 demi-tons)unstableCaug = C–E–G#