Alarm call

Could someone describe or post a video or otherwise acquaint me with the difference between a cockatoo's "I'm bored; where are you; it's morning/noon/night; I just like the sound of my own scream" yelling and actual alarm or distress? I can tell with the others (budgie, tiel, quaker) not only when it's just a contact call and when it's actual alarm, but which of them is shrieking. But Rocky's regular yelling can range from sounding like a fretful baby to a full blown tornado siren and I worry that I'll be in another room and he'll be in actual distress and I won't realize it because I'll think he's just yelling, since there's such variety in his "just yelling." Several times already I've come running from the other end of the house only to find him calmly sitting on his door blinking at me (OH! There you are!) when I thought he was in trouble. The stinker. Yes, I've told him the story of The Too Who Cried Wolf.

It may vary by species, but with my Goffins the "alarm" screech seems higher pitched, and is a continuous staccato cadence. I've been in the room when they erupt, and it's kind of fun putting my nose right up to the beak to smell their breath! Yes, they look at me as if I were crazy!