making beep sound.

beep.js

  const audioCtx = new(window.AudioContext || window.webkitAudioContext)();
  
  const beep = function(){
    if(settings.beep === 1) {
      return false;
    }
    const volume = 0.1
    ,   duration = 200
    ,   type =  'square'
    ,   frequency = 2000 /*1000*/;
    const oscillator = audioCtx.createOscillator();
    const gainNode = audioCtx.createGain();
    
    oscillator.connect(gainNode);
    gainNode.connect(audioCtx.destination);
    
    gainNode.gain.value = volume;
    oscillator.frequency.value = frequency;
    oscillator.type = type;
    
    oscillator.start();
    setTimeout(function() {
    	oscillator.stop();
    }, duration);
  };