Chord quality

In Western music, the adjectives major and minor can describe a musical composition, movement, section, scale, key, chord, or interval.

Major and minor are frequently referred to in the titles of classical compositions, especially in reference to the key of a piece.

With regard to intervals, the words major and minor just mean large and small, so a major third is a wider interval, and a minor third a relatively narrow one. The intervals of the second, third, sixth, and seventh (and compound intervals based on them) may be major or minor.

The other uses of major and minor, in general, refer to musical structures containing major thirds or minor thirds. A major scale is one whose third degree is a major third above the tonic, while a minor scale has a minor third degree. A major chord or major triad, similarly, contains a major third above the root, whereas a minor chord or minor triad contains a minor third above the root. In Western music, a minor chord, in comparison, "sounds darker than a major chord".

The hallmark that distinguishes major keys from minor is whether the third scale degree is major or minor. "The crucial difference is that in the minor scale there is only a half step between "2nd and 3rd note" and between "5th and 6th note" as compared to the major scales where the difference between "3rd and 4th note" and between "7th and 8th note" is half." This alteration in the third degree "greatly changes" the mood of the music, and "music based on minor scales tends to" be considered to "sound serious or melancholic".

The minor scale can be described in two different ways. One way is to consider it as the sixth mode of a major scale, while the other is to call it a variation of the major scale, with the third scale degrees always lowered (or altered) and the sixth and seventh degrees often lowered.

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