As I understand it, the terms duple, triple, quadruple, etc refer to the number of beats in the measure. So if my measure is divided into 3 beats, then I'd be in triple meter. For example,
X: 1
M: 3/4
K: Cmaj
L: 1/4
""G""G""G |""G""G""G|
However, I'm confused about simple vs compound. Consider this answer.
https://music.stackexchange.com/a/71106/15674
Here are some diagrams from the answerer.
X: 1
M: 3/4
K: Cmaj
L: 1/8
"1"G"+"G "2"G"+"G "3"G"+"G|
X: 1
M: 6/8
K: Cmaj
L: 1/8
"1"G"+"G"a"G "2"G"+"G"a"G|
So he says that 3/4 is simple triple and 6/8 is compound duple.
From what I understand, the reason is that each beat in 3/4 can be divided into 2 while each beat in 6/8 can be divided into 3.
But I find this confusing because in 3/4, there are 3 quarter notes. And they haven't yet been divided into anything. If we divided them by 2, then yes, it would be "simple triple", like this:
X: 1
M: 3/4
K: Cmaj
L: 1/8
""G""G ""G""G ""G""G |
But what if I wanted to divide each beat by 3s?
I could also divide each beat by 7.
The first example is a triplets and the second example is septuplets. In both these examples, the number of beats in the measure would still be 3. So it would still be triple meter. But they wouldn't be "simple" because the beats aren't divided into 2.
So this is where I'm confused. It seems like "simple triple" should only refer to this
X: 1
M: 3/4
K: Cmaj
L: 1/8
""G""G ""G""G ""G""G |
and not this
X: 1
M: 3/4
K: Cmaj
L: 1/4
""G""G""G |""G""G""G|
because the beats in the second case could be divided into any number of notes.
So my question is, why would we say 3/4 is "simple triple" if the beats can be divided into other values besides 2? Isn't it a meaningless distinction then?