Usage no npm install needed!

<script type="module">
  import helmholtz from 'https://cdn.skypack.dev/helmholtz';
</script>

README

helmholtz

Parsing notes written in Helmholtz pitch notation returning intervals in octaves and fifths relative to A4 (or a')

var helmholtz = require('helmholtz');

helmholtz('a\'') // -> [ 0, 0 ]
helmholtz(',,C') //  -> [ -3, -3 ]
helmholtz('d#\'') // -> [ -4, 6 ]
helmholtz('a\'\'') // -> [ 1, 0 ]

usage

var helmholtz = require('helmholtz');

helmholtz(note)

Takes a note string in the Helmholtz notation and returns an array describing the interval of that note relative to A4. The returned interval is in the format [octaves, fifths] - that is, an array consisting of two numbers, the first the number of octaves to jump, the second the number of fifths to jump from A4 to land at the desired note.