Tonality is a common hierarchical framework in use in western music from approximately 1600 CE or so. For some of western music history, tonality is the best way to describe pitch relationships in music. Starting toward the end of the 19th Century and the beginning of the 20th, tonality became less straightforward, and eventually multiple styles of music that did not use tonality at all became prevalent. Music in western Europe before 1600, largely speaking, is described with various types of modes, which were “rediscovered”/reinvented in the 20th Century and are now quite common in many styles of music. However, tonality has not completely disappeared, and many current styles of music consciously or subconsciously play off of tonal tropes in pitch, rhythm, motivic, and structural ways.
Western European Tonal Harmony is distinctive in that is one of the first styles of music to use chords and vertical structural relationships. Many other styles of music from before 1600 or around the globe focus on melodic horizontal relationships, sound color (timbre) shifts, or rhythmic developments. These other properties of music are also very important to western music, but the study of western music and music theory is the first place that focuses on chords and chordal relationships. Since the advent of globalization, and the proliferation of musical styles in the 20th Century, other genres of music have used vertical structural relationships, but this is often one of those conscious or unconscious tonal influences on modern music.
With the overview of the basic cultural context out of the way, how does tonality work?
A piece that uses tonality is said to be tonal and exists in a key. This key is defined by a tonic, or tonal home base. The tonic is the name of the key (C major), the individual note (C), and a triadic chord built on that note. Other notes and chords will have varying degrees of instability that move the music back toward tonic. Most tonal pieces end on tonic, and many start there as well.
Tonic is defined thru this hierarchical instability as various notes and chords pull to the tonic. Other types of music that have a pitch center without being tonal (either modal or just centric music) can define their home base/pitch center with other means (repetition, melodic tropes, rhythm, absence; but the difference between centric music and tonal harmony is the chordal and pitch hierarchy that defines the tonic.
Exploring the relationships in this hierarchy is what Functional Analysis is designed to do. Functional chord labels show the relationship between chords, and solfège can be use to show the relationship between melodic pitches in a functional sense. (Even purely melodic pieces can have tonal harmony, because while chords are often vertical, they can also be expressed horizontally.)
As I move on to the next bit of Music Fundamentals (keys, chords), I find these are much easier to understand in a tonal context. Depending on the type of music you are most familiar with, learning about keys and tonality can also help with note reading fluency.
If you already have a basic understanding of Music Fundamentals, you can learn more about Tonality by starting the Functional Analysis blog post sequence with Cadence and Form: https://functionalanalysis.blog/2016/12/21/lesson-1-cadence-and-form/
Next post should be major keys, but I don’t know if it will be this week or next week.