public Progression(string key, string mode)
 {
     _key  = NoteFactory.getNoteByName(key);
     _mode = new Mode();
     _mode = ModeFactory.getModeByName(mode);
 }
 public void changeMode(string mode)
 {
     _mode = ModeFactory.getModeByName(mode);
 }
 public Progression()
 {
     _key  = new Note(4, "C");
     _mode = new Mode();
     _mode = ModeFactory.getModeByName("Ionian");
 }