If you take an instrument without predefined notes, such as a trombone or a violin, you can produce an infinite amount of notes between Do and Re for example (applies with out of tunes instruments as well). With that logic, you could have an infinite set of 7 notes that are as evenly « spaced » as our current standard. Im sure im missing something obvious.
In: Physics
One theory is that it’s derived from something called the Harmonic series. Hopefully I’m allowed to link to another source in this subreddit, because Leonard Bernstein does a great job of demonstrating and ELI5 here. He walks through how you can arrive at major chords. If you continue extending it, you end up with a major scale, which are that the notes Do Re Mi Fa Sol La To Do represent.
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