cross browser html 5 audio playback example

x-browser-audio

  function supports_audio() {
    return !!document.createElement('audio').canPlayType;
  }
  function supports_audio_type(audioType) {
    if (!supports_audio()) { return false; }
    var a = document.createElement("audio");
    return a.canPlayType(audioType);
  }
  var alertFile = supports_audio_type("audio/ogg") ? "/sounds/redalert.ogg" : (supports_audio_type("audio/mp4") ? "/sounds/redalert.mp4" : '');
  if (alertFile) {
    var alert = new Audio(alertFile);
    alert.play();
  }