vocal-exercises/index.js

Some scripts for vocal exercises

"use strict";

var baudio = require("baudio");

var tau = Math.PI * 2;

var melody = [440, 466.16, 493.88, 523.25, 554, 587.33, 622.25, 659.25, 698.46, 739.99, 783.99, 830.61, 880.00];

var b = baudio(function (t) {

    var n = t * 0.3 % 3 + 1;
    var f = Math.sin(tau * tau / ((n * 6 % 1 + 0.5) * 2));
    var drums = Math.sin(tau * n * f);
    var now = 0;
    now = drums;
    var note = melody[Math.floor(t * 0.3 % melody.length)];

    now += sawtooth(note) + sawtooth(note + 3) + square(note);

    function sin(freq) {
        return Math.sin(tau * t * freq);
    }

    function square(freq) {
        return Math.sin(tau * t * freq) < 0 ? -1 : 1;
    }

    function sawtooth(freq) {
        return t % (1 / freq) * freq * 2 - 1;
    }

    return now;
});

b.play();