I am excited to see this thread here - I have been arguing for years on this board that more audiophiles should educate themselves more about the music they listen to, as this will only increase their enjoyment. There have been some great comments here.
Rok, Mapman and Brownsfan have made good stabs at answering your question. However, if you really want to understand the changes in music over time, you need to understand more about music in the first place. I am not being condescending here - it really is difficult to discuss music without using musical terms. For you and anyone else interested, the very best book I know of for musical "laymen" is Aaron Copland's What To Listen For In Music. If you are more of a DVD/CD kind of guy, another great place to start would be those Great Courses series - pretty much anything that is done by Robert Greenberg. He is excellent at explaining music to non-musicians, and he has a couple of different courses available from that company on music history and music theory. He is fantastic. I took a couple of grad seminars from him in college, so yes I have personal experience with him.
Rok, Mapman and Brownsfan have made good stabs at answering your question. However, if you really want to understand the changes in music over time, you need to understand more about music in the first place. I am not being condescending here - it really is difficult to discuss music without using musical terms. For you and anyone else interested, the very best book I know of for musical "laymen" is Aaron Copland's What To Listen For In Music. If you are more of a DVD/CD kind of guy, another great place to start would be those Great Courses series - pretty much anything that is done by Robert Greenberg. He is excellent at explaining music to non-musicians, and he has a couple of different courses available from that company on music history and music theory. He is fantastic. I took a couple of grad seminars from him in college, so yes I have personal experience with him.