Date: April 2004
How does a dog whistle work?
Dog whistles are simple.
The only secret about it is that dogs can hear sounds of higher pitch than people can.
So we make an ordinary whistle with a very high pitch.
A whistle is just an air nozzle squirting air at an edge, right next to the hole in the end
of a tube which likes to "ring" at the chosen pitch.
A long tube will ring at a low pitch, a short tube at a high pitch.
So a dog-whistle has a very short little tube, only 1 inch long or shorter.
If you look at a dog whistle, you can usually find this tube.
If you could make the tube longer, you would start to hear the whistle.
I guess dogs don't hear loud sounds this high-pitched very often, so they really notice.
It might even hurt their ears, just like a loud whistle can hurt your ears, if the whistle
But mostly, when a dog hears a dog-whistle, it just does whatever it was trained to do when
it hears a dog-whistle.
And maybe he was never trained! Then the whistle has no special power far away.
If you are training your dog, any whistle is a good thing. A whistle is simpler for a dog
to notice than words.
To him it's a distinct, clear, simple, special barking with no words.
Like barking, it is either there or it's not. The dog only needs to interpret the occasion
of the whistle-blow,
("he tweeted at me when I got up, so maybe he wants me to sit down"...)
not the vowels and consonants and sentences people keep hoping the dog will understand.
Dogs aren't very good at hearing vowels and constants, let alone sentences.
It just isn't built into their brains yet.
They'd rather hear one toot or two, or long and short. Things like that.
High/Low pitch is good if the pitch difference is large, and rising and falling are even
Steady vs. fluttery is good too.
It's more about understanding the dog, than about understanding whistles.
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Update: June 2012