Diatonic scale

In Music theory, the diatonic major scale is a fundamental building block of the Western musical tradition. It contains seven notes to the octave, corresponding to the white keys on a piano, obtained from a chain of six successive fifths in some version of meantone temperament, and resulting in two tetrachords separated by intervals of a whole tone. If our version of meantone is the twelve tone equal temperament the pattern of intervals in semitones will be 2-2-1-2-2-2-1. The major scale begins on the first note and proceeds by steps to the first octave. In solfege, the syllables for each scale degree are "Do-Re-Mi-Fa-Sol-La-Ti-Do".

The natural minor scale can be thought of in two ways, the first is as the relative minor of the major scale, beginning on the sixth degree of the scale and proceeding step by step through the same tetrachords to the first octave of the sixth degree. In solfege "La-Ti-Do-Re-Mi-Fa-Sol."

Alternately, the natural minor can be seen as a composite of two different tetrachords of the pattern 2-1-2-2-1-2-2. In solfege "Do-Re-Mé-Fa-Sol-Lé-T&eacute-Do."

Western harmony from the Renaissance up until the late nineteenth century is based upon the diatonic scale and the unique relationships created by this system of organizing seven notes. It should be kept in mind that most longer pieces of common practice music change key, but this leads to a relationship of diatonic scales in one key with those in another, see modulation.

The white keys on a piano correspond to the diatonic scale of C major (C-D-E-F-G-A-B-C), with the notes a whole tone apart, except for E-F and B-C, which is an interval of a semitone (half a tone).

Diatonic comes from the greek "diatonikos" or "to stretch out". It is sometimes used to refer to all the modes, but is generally used only in reference to the major and minor scales.