Major triad

A major triad is a triad comprising a root, major third, and perfect fifth.

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Major chord

In just intonation

In the 5-limit:

• 4:5:6 is found on the I (1⁄1), IV (4⁄3), and V (3⁄2) of Ptolemy's intense diatonic scale (Zarlino).

In the 3-limit:

• 64:81:96 is found on the I, IV, and V of the Pythagorean diatonic scale.