var FrequencyBars = require('frequency-bars')
var html = require('nanohtml')
 
var bars = new FrequencyBars()
var audio = new Audio('./path/to/audio.mp3')
 
document.body.appendChild(html`
  <div>
    ${bars.render({
      width: 400,
      height: 240,
      background: '#222',
      audio
    })}
  </div>
`)
 
audio.play()