code: func NoteOff(channel, key int) *Event {
  	return &Event{
  		MsgChan:  uint8(channel),
  		MsgType:  uint8(EventByteMap["NoteOff"]),
  		Note:     uint8(key),
  		Velocity: 64,
  	}
  }
docs: // NoteOff returns a pointer to a new event of type NoteOff (without the delta timing data)