I've never heard of anything higher than 13.

I guess this is because the main intervals we express are odd ... 1, 3, 5, 7, 9, 11 & 13, but the 9, 11 & 13 equate to even interval notes in the next octave up, then 15 would be back to the root note again. There's no need to continue.


Jazz relative beginner, starting at a much older age than was helpful.
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