The musical tug-of-war between the white keys and the chromatic scale
In short: In music theory, the distinction between diatonic and chromatic is rarely clear-cut. While we often think of diatonic as the familiar white notes of a piano, the actual definition shifts depending on whether you are studying ancient Greek lyres, Renaissance notation, or 1'9th-century harmony.
At its simplest, 'diatonic' refers to notes derived from a specific scale, often the white-key sequence from C to B. 'Chromatic' refers to the use of all twelve semitones in equal temperament. However, these terms have historically functioned as a spectrum of tuning. In ancient Greek music theory, the lyre featured three distinct 'genera' or tunings: the diatonic, the chromatic, and the even more microtonal enharmonic, which utilized quarter tones. In a diatonic tetrachord, the sequence of four notes descends through two whole tones and one semitone. Conversely, the chromatic version lowers the second string to create two consecutive semitones.
The concept of 'chromatic' has also undergone significant semantic shifts. During the 14th to 16th centuries, 'chromatic' could refer to a rhythmic convention where notes were 'colored' (often in red) to indicate a change in meter. By the 16th century, the term began to describe the use of semitones and frequent key changes, a shift influenced by theorists like Nicola Vicentino and composers like Orlando Lasso. In the 16th century, the term was also used to describe madrigals, which were characterized by an abundance of black notes. This usage is the ancestor of the modern term coloratura.
Today, the boundary remains a subject of debate among theorists. Some classify all major and minor scales as diatonic, while others argue that variants like the harmonic or melodic minor are non-diatonic because they deviate from the standard white-key pattern. This ambiguity extends to harmony: some define chromatic harmony as the use of chords from different keys, such as through secondary dominants, while others see it simply as any chord containing notes outside the primary scale. This ambiguity even affects intervals; for instance, a B-natural to E-flat might be labeled chromatic or diatonic depending on whether the harmonic minor scale is included in the definition. Furthermore, in certain temperaments, the interval of a major third can be accompanied by a diminished fourth that is less consonant.
Opens the Intellect+ feed with this card first. Swipe up for the next one.
Sources
- Summary by Intellect · source: Diatonic and chromatic
To cite this card, link to https://intellectplus.co.uk/app/music-diatonic-and-chromatic.
How we source, check and correct cards: Editorial standards.
General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.
Intellect Plus is a visual educational discovery platform for exploring fascinating facts and ideas. Brain Food, Not Brain Rot. What is Intellect Plus?
Related
More in Harmony · More in Music · Latest · A–Z · All topics
