What is a diminished triad?

What is a diminished triad?

• A. A chord with two minor thirds
• B. A chord with two major thirds
• C. A chord with a major third on bottom and a minor third on top
• D. The lowest of the three notes in a triad

Answer: (A)

A diminished triad is built by stacking two minor third intervals on top of the root. That means the chord has a root, a note a minor third above, and a third note another minor third above that, totaling a diminished fifth from the root. For example, C diminished triad is C, Eb, Gb. This structure—two minor thirds—defines the quality. If you instead stack two major thirds you’d get an augmented triad, which sounds different (C, E, G#). If you place a major third on the bottom and a minor third on top, you’d form a major triad (root, major third, perfect fifth). The statement about the lowest note being the root is just a feature of any triad, not what makes it diminished.

A diminished triad is built by stacking two minor third intervals on top of the root. That means the chord has a root, a note a minor third above, and a third note another minor third above that, totaling a diminished fifth from the root. For example, C diminished triad is C, Eb, Gb. This structure—two minor thirds—defines the quality. If you instead stack two major thirds you’d get an augmented triad, which sounds different (C, E, G#). If you place a major third on the bottom and a minor third on top, you’d form a major triad (root, major third, perfect fifth). The statement about the lowest note being the root is just a feature of any triad, not what makes it diminished.