Future<Sound> loadDataUrl(String dataUrl, [ SoundLoadOptions soundLoadOptions ])

Loads a sound from a data url.

Please be aware that browsers do support different kinds of audio types. You can get a list of supported types here: Sound.supportedTypes

var sound = await Sound.loadDataUrl("data:audio/mpeg;base64,<data>");
sound.play();

Source 

static Future<Sound> loadDataUrl(
    String dataUrl, [SoundLoadOptions soundLoadOptions]) async {

  var options = soundLoadOptions ?? Sound.defaultLoadOptions;
  var audioContext = WebAudioApiMixer.audioContext;
  var start = dataUrl.indexOf(',') + 1;
  var bytes = BASE64.decoder.convert(dataUrl, start) as Uint8List;

  try {
    var audioData = bytes.buffer;
    var audioBuffer = await audioContext.decodeAudioData(audioData);
    return new WebAudioApiSound._(audioBuffer);
  } catch (e) {
    if (options.ignoreErrors) {
      return MockSound.loadDataUrl(dataUrl, options);
    } else {
      throw new LoadError("Failed to load sound.", e);
    }
  }
}