message: updating bell part to new MetalSynth api
diff: }).toMaster();
  var bellPart = new Tone.Sequence(function(time, freq){
  - bell.frequency.setValueAtTime(freq, time, Math.random()*0.5 + 0.5);
  - bell.triggerAttack(time);
  + bell.triggerAttack(freq, time, Math.random()*0.5 + 0.5);
  }, [[300, null, 200],
  [null, 200, 200],
  [null, 200, null],
  