
Barry S. answered 03/01/21
A New Look at Music Theory/Analysis, Composition, and Songwriting
I agree with pretty much everything Alden said. I would only add that in tonal music of the17th through 19th centuries the cadence at the end of a phrase followed strict tonal procedures. The procedures of atonal or twelve-tone music, however recognize no cadential prototype. A "cadence" in such music would be whatever structure the composer chooses to end a phrase. In some 20th - 21st century music the idea of phrase structure is inapplicable.