audioAPI-example.js

window.AudioContext = window.AudioContext || window.webkitAudioContext
class AudioPlayer {
  constructor () {
    this.context = new AudioContext()
  }

  // Audio 用の buffer を読み込む
  getAudioBuffer (url, callback) {
    const req = new XMLHttpRequest()
    req.responseType = 'arraybuffer' // array buffer を指定
    req.onreadystatechange = () => {
      if (req.readyState === 4) {
        if (req.status === 0 || req.status === 200) {
          this.context.decodeAudioData(req.response, callback)
        }
      }
    }
    req.open('GET', url, true)
    req.send()
  }

  playSound (url) {
    this.getAudioBuffer(url, buffer => {
      const source = this.context.createBufferSource()
      source.buffer = buffer
      source.connect(this.context.destination)
      source.start(0)
    })
  }
}

const audioPlayer = new AudioPlayer()
audioPlayer.playSound(`sounds/apple.wav`)