Musical Composition, Theory and Songwriting/Basic chord progressions of classical music
May I ask this question?
Original classical music sheets do not have the chords, so I don't know if they have any relations to modern pop music.
For example, some melodies are very popular like Canon in D, Air on the G String, etc. Do they have the same chord progressions as modern pop songs?
Hello Mick, and thanks for being patient. I'm in the throes of the exam term.
All genres of Western music from the 16th to early 20th century are based on a key system which had completely superseded the earlier modal system by the late 17th century, and established its rules during the 18th century. The rules I'm referring to determine what constitutes concord and discord, and how the latter is to be approached and resolved. There was a certain amount of experimentation within the rules, but it wasn't until the 19th century that the rules were first bent, then progressively broken, until by the beginning of the 20th century they could no longer be said to apply and composers either made a conscious decision to return to them or attempted to formulate new systems of their own. (Since 1945 there's been pointillism, post-Webernism, integral serialism, free dodecaphony, aleatory and indeterminate music, musique concrete, electronic music ...).
The basis of the key system is that: the octave is divided into 12 equal semitones; the two predominating diatonic scales, major and minor, are constructed in exactly the same way in all 12 keys; the various degrees of the scale and the triads built up on them are of greater or lesser importance in relation to the keynote; and we have the concept of "related" keys, which makes it easy to move from one key to another, either directly or via other, more closely related, keys. (This is modulation, and it is the ability to modulate that makes Western music unique.) So once you have firmly established your home key, you have a network of interconnections and interrelations that underpins every note you write.
Until the 19th century there was no separate category of "popular" music. In medieval times the Christian church dictated how the octave was to be divided (into eight modes), how words were to be set and how parallel lines of melody were to fit together so as not to obscure the text, and the church's strictures underpinned Western music for six centuries. By definition sacred music tended to be more conservative than secular music, although composers moved easily between the two. The usual pattern was that the church set the rules; composers kept them when writing sacred music but experimented in their secular works (bear in mind that the use of instruments was frowned upon for a long time by the church as frivolity); gradually a new style or technical development became commonplace and started to appear in sacred works. Then the church stepped in and tried to ban it or, when that didn't succeed, at least define the rules for its use. By the time the new key system had established itself, there was no difference in harmonic vocabulary between sacred and secular music.
The big change came in the 19th century. The Romantic movement delighted in flouting the established rules of harmony changed so that chords previously defined as discordant became part of the standard musical vocabulary and modulations to unrelated keys became more and more outlandish. If Baroque and Classical composers wrote music that the people, or at least their patrons, wanted to hear, Romantic composers wrote music for the audience of a future time when their creative vision would be vindicated. The cliche of the genius misunderstood by society and starving in an attic for the sake of his art pretty much defines Romanticism.
So 19th-century audiences went to concerts to hear and criticise virtuoso performer-composers, but they also wanted music they themselves could play at home, so for the first time there was a separation between "art" or "classical" music, which looked forward, and "popular" music, which looked backward to a simpler, more clear-cut harmonic vocabulary - parlour music, music hall and vaudeville, the songs of Tin Pan Alley. In America, immigrant populations settled in particular regions, bringing their traditional music with them and combining it with European harmony to produce a whole variety of popular music under the umbrella "roots music" - bluegrass, Appalachian, Cajun etc - and African music plus European harmony brought gospel, ragtime and eventually jazz and its offshoot swing.
Finally, the 1950s brought a new genre (rock 'n' roll) and a new audience demographic (teenagers), and modern pop music arrived. I don't know much about the history of pop or its various genres (Wikipedia lists 55, most of which I've never heard of) but I've spent a couple of hours on Youtube listening to compilations, and a good 70% of the clips use straightforward unadorned chords in a harmonic vocabulary that's straight out of the 18th century. Rock music has certain conventions - unresolved suspensions, chords with added 7ths, borrowed chords - but even when they're present the underlying harmonic progression is clearcut.
Hope this helps, and thanks again for being patient.