Heavy metal is built on power chords and modal progressions.

• A. True
• B. False
• C. Not sure
• D. It is built on simple triads and blues scale runs

Answer: (A)

Heavy metal’s charged, heavy sound comes from two defining choices: power chords and modal thinking. A power chord is usually just the root and the fifth (often with the octave added). That minimalist chord shape, when played with high gain/ distortion, delivers a thick, aggressive punch without the complexity of full triads. It gives riffs the bite and tightness that define metal guitar, especially when palm-muted and riff-driven.

Pair that with modal progressions. Instead of relying on straightforward major/minor I–IV–V progressions, many metal riffs explore modes such as natural minor (Aeolian), Dorian, or even Phrygian (and its Phrygian dominant flavor in some subgenres). These modes provide darker, more ambiguous tonal centers and color, which contribute the distinctive mood and tension metal riffs seek. That combination—the stark, powerful sound of power chords plus the color and flexibility of modal scales—best captures what metal is built on.

Some metal riffs may incorporate full triads or blues/pentatonic patterns, but those elements aren’t the defining foundation the genre is known for.