The main question I have is admittedly broad. I'd like to know why the notes we use today are the way they are. By that I mean how is it that we have converged upon the specific discrete set of notes commonly found on Western instruments such as the piano.
Though some have asked, why are there 12 notes in an octave, I am not only curious about this but about the specific choice of both the number of intervals as well as the relation between intervals. Some questions that come to mind related to this are:
- We have more notes in an octave than we use in any key so why do we need them?
Here we have all the notes: Cb, C, C#, Db, D, D#, Eb, E, E#...(so goes on) Bb, B, B#.
How did we decide on the spacing between half steps?
I can hear notes in between a half step so why aren't they part of music? At least why not part of the list of notes I mentioned above?
I hear of terms like concert Bb, or A, and thought that A was defined as 440Hz. Yet I also see other numbers like 432Hz.
4a. Which is it?
4b. And why is it a set value?
4c. Could it be any random value and be called an A?
- Related to Q1. How was it that a specific set of 8 notes became a "key"? Why not choose a set of 10 notes, or 5 notes and call it a key?
I am assuming that the "keys" were chosen from the list I provided but perhaps that is false. I really want to know which came first.
I realize that there seem to be a lot of sub-questions and that stack exchange prefers one at a time but I'm merely trying to provide context. Without a deep understanding it's hard to frame the question. So I guess what I'm really interested is a bit of music history, why is it that Western music has evolved into the specific set of notes we have today? Was it always that way? Could it have been different?