Minor sixth

In music theory, a minor sixth is a special kind of musical interval that covers six staff positions. It is called "minor" because it is smaller than another common interval called the major sixth. The minor sixth includes eight tiny steps, called semitones, between two notes. For example, if you start at the note A and move up to the note F, you have played a minor sixth because there are eight semitones between these two notes and they are six positions apart on the musical staff.

There are also other intervals that cover six staff positions, such as the diminished and augmented sixths, but they have a different number of semitones — seven and ten respectively. These intervals are important in music because they help create different sounds and feelings in songs and compositions. Understanding intervals like the minor sixth helps musicians and composers build harmony and melody in their work.

Equal temperament

In 12-tone equal temperament, the minor sixth is the same as the augmented fifth when you look at the notes differently. It appears in certain major and minor chords. The minor sixth is eight semitones apart, which is a ratio of 2^8/12:1, or about 1.587, and equals 800 cents.

Just intonation

In just intonation, the minor sixth can have a few different definitions. In Pythagorean tuning, it uses the ratio 128:81, which is a bit lower in pitch than the common tuning. In 5-limit tuning, the minor sixth is often 8:5, which is a bit higher in pitch. There is also an 11-limit tuning version called the undecimal minor sixth.

The minor sixth is considered a pleasing interval in music, along with the unison, octave, perfect fifth, and major sixth. It was not always seen this way—long ago, in medieval times, it was thought of as a clashing sound. But in more recent music history, it has been valued for its interesting sound.