The α scale is a non-octave-repeating musical scale

Musical scale

In music, a scale is a sequence of musical notes in ascending and descending order. Most commonly, especially in the context of the common practice period, the notes of a scale will belong to a single key, thus providing material for or being used to conveniently represent part or all of a musical...

 which splits the minor third

Minor third

In classical music from Western culture, a third is a musical interval encompassing three staff positions , and the minor third is one of two commonly occurring thirds. The minor quality specification identifies it as being the smallest of the two: the minor third spans three semitones, the major...

 (just: 315.64 cents , 12-tet: 300 cents , Alpha scale: 312 cents ) into two equal parts, or four equal parts of approximately 78 cents each . This totals approximately 15.39 steps per octave

Octave

In music, an octave is the interval between one musical pitch and another with half or double its frequency. The octave relationship is a natural phenomenon that has been referred to as the "basic miracle of music", the use of which is "common in most musical systems"...

. It may be derived from using 9:5 to approximate the interval 3:2/5:4, which equals 6:5 .

It was invented by Wendy Carlos

Wendy Carlos

Wendy Carlos is an American composer and electronic musician. Carlos first came to notice in the late 1960s with recordings made on the Moog synthesizer, then a relatively new and unknown instrument; most notable were LPs of synthesized Bach and the soundtrack for Stanley Kubrick's film A...

 and used on her album Beauty in the Beast

Beauty in the Beast

Beauty in the Beast is an album by Wendy Carlos using alternate tunings and scales and influenced by jazz and world music. On the back she includes a quote by Van Gogh: "I am always doing what I cannot do yet, in order to learn how to do it."...

(1986).

The alpha scale produces, "wonderful triads

Triad (music)

In music and music theory, a triad is a three-note chord that can be stacked in thirds. Its members, when actually stacked in thirds, from lowest pitched tone to highest, are called:* the Root...

," ( and ) and the beta scale

Beta scale

The β scale is a non-octave-repeating musical scale which splits the perfect fourth into two equal parts, or eight equal parts of approximately 64 cents each . This totals approximately 18.75 steps per octave...

 has similar properties but the sevenths

Harmonic seventh

The harmonic seventh interval , also known as the septimal minor seventh, or subminor seventh, is one with an exact 7:4 ratio . This is somewhat narrower than and is "sweeter in quality" than an "ordinary" minor seventh, which has a just-intonation ratio of 9:5 , or an equal-temperament ratio of...

 are more in tune. However, the alpha scale has, "excellent harmonic seventh chord

Harmonic seventh chord

The harmonic seventh chord is a major triad plus the harmonic seventh interval . This interval is somewhat narrower than and is "sweeter in quality" than an "ordinary" minor seventh, which has a just-intonation ratio of 9:5 , or an equal-temperament ratio of 1000 cents...

s...using the inversion of 7/4, i.e., 8/7

Septimal whole tone

In music, the septimal whole tone, septimal major second, or supermajor second is the musical interval exactly or approximately equal to a 8/7 ratio of frequencies. It is about 231 cents wide in just intonation. Although 24 equal temperament does not match this interval particularly well, its...

." More accurately the alpha scale step is 77.965 cents and there are 15.3915 per octave.