Influenced by European tuning systems used before 1700 and by non-Western music, there were numerous composers in Europe and North America who began to experiment with microtonal structures soon after 1900. While the term might suggest that it is not the norm, in fact, most of the world’s music uses intervals greater or smaller than 100 cents. Microtonality, in essence, uses tones that exist between the notes of the 12-note, equal-temperament scale that is used in most Western music. It is these in-between notes, the ones that are in between the standard tones, that are called microtones. Taking this example further, even though a piano keyboard indicates a fixed arrangement of standard pitches, our ears can actually discern another 20 pitches or so between each of the keys. It was after this that artists in Western music began to rely on a set of fixed pitches spaced at equidistant intervals, as the keys on a piano. The tuning system used most commonly in Western music dates back to 1917 according to some academics, with the publication of William Braid White’s Modern Piano Tuning and Allied Arts.
This varies from culture to culture and changes over time. In contemporary music, while it appears that there is a standardized system of tuning, in reality, the manner in which an instrument is tuned or even whether it is considered to be “in tune” is not objective or universal.
