I have read it. It is very vague about what is actually happening. I have asked a few physics professors about how whistling works.
One person is absolutely adamant that the vibrations are caused because of the air being pressurized as it goes out the lips, causing the lips to vibrate...
The physics behind human whistling--where does the sound come from?
In most whistles, air is split somehow. When humans whistle (by forming a small hole with their lips), this is definitely not the case. I would assume that the mouth is the resonance chamber because pitch can be altered by...