message: define left and right variables
diff: @@ -106,6 +106,8 @@ function (OutputAudio, Effect, PassAudio, PassAudioStereo, Test, Offline, Signal
  instance.start();
  }
  }, 0.5, 2).then(function(buffer){
  + var leftEffected = false;
  + var rightEffected = false;
  buffer.forEach(function(L, R, time){
  var leftValue = (time * 2) - 1;
  var rightValue = ((1 - time) * 2) - 1;
  