It is my understanding that all Cessnas have the reed stall warner even those that are fitted with electric stall warners.
The stall warner is a reed that is mounted in the wing root just beside the cabin vent on the pilot side. There is an opening on the wing route that as the angle of attack increases causes air to be drawn over the reed which makes it vibrate. The vibration is amplified by a small horn type arrangement and its this combination that makes the wheezing wailing sound that you can hear on the video.
After a thousand or so hours in them I would recognise that sound anywhere.