Diatonic harmony was developed and defined in the era of music making of the 19th century. The correct option is a. 19th.
Diatonic harmony is a term used in music theory to describe the chords that are created using only the notes of a particular scale. These chords are also known as diatonic chords, and they are the foundation of many Western music compositions.
The most commonly used diatonic chords are triads, which are three-note chords consisting of a root note, a third, and a fifth. In a major scale, the diatonic chords are typically made up of the notes of the scale, and they are usually in a particular sequence. Arrangement of the Diatonic Harmony. The diatonic chords of a major scale can be organized in the following order: major, minor, minor, major, major, minor, and diminished.
This order can be remembered using the acronym "Mm7Mm7d," which stands for major, minor, seventh, major, minor, seventh, diminished. However, it should be noted that this is just one way of organizing the diatonic chords of a major scale, and other sequences are also possible.
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