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🌀Mysterious
augmented

Chord Detail

Caug

C Augmented Triad

Caug is a C augmented triad — formed by raising the fifth of a major triad by one semitone. This creates two stacked major thirds and a restless, ambiguous sound that sits between major and something entirely unresolved.

CRoot
E
Ab

Theory

The augmented triad is built from two stacked major thirds: 4 semitones above the root, and another 4 semitones above that (8 semitones total = an augmented fifth). Caug uses C, E, Ab. The augmented fifth (Ab) creates tension — it is one semitone above a perfect fifth, making the chord feel unstable and yearning. The augmented triad is symmetrical: every inversion produces the same set of pitch classes. This is why it sounds rootless and floating. In harmonic practice, augmented chords typically appear as passing chords or tension chords before resolution. In jazz, they often substitute for the V chord for a more colorful approach.

Intervals & Formula

Formula: 1 – 3 – ♯5

1Root0 semitones
3Major Third4 semitones
♯5Augmented Fifth8 semitones

Sound Character

Mysterious, ambiguous, tense, and exotic. Neither clearly major nor minor — it floats in harmonic ambiguity.

Musical Meaning

Augmented chords replace the perfect fifth with an augmented fifth, creating a dreamy, harmonically ambiguous sound. Because every interval is equidistant, they have no clear tonal center — making them perfect for unexpected transitions and harmonic color.

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Voicing Tips

The augmented triad is symmetrical — each interval is 4 semitones. This means inverting it produces an enharmonically equivalent chord. Use sparingly and let it resolve. On piano, raise just the fifth of a major chord by one semitone. Works well in slow harmonic rhythm as a surprise color chord.

Practical Uses

  • Chromatic passing chord between I and IV (augmented on the 5th scale degree)
  • Dramatic tension before resolution in film scores
  • III+ chord in minor keys leading to the iv chord
  • Coloristic chord in jazz ballads for harmonic ambiguity

Common Progressions

1I – I+ – IV (Chromatic inner voice)
2V+ – I (Augmented dominant approach)
3III+ – vi (Minor movement)
4I – III+ – VI (Ascending chromatic)

Related Chords

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