A dog whistle (as silent dog whistle or whistle Galton) is a type of whistle sounds emitted in the ultrasonic range, that people can not hear, but other animals, including dogs and cats, and is used in its formation. It was mentioned in 1876 by Francis Galton, such as a house cat invented and in its deliberations on the books human capacity and its development to test the experiments the frequency range that describes to hear from different animals.
The maximum upper range of human hearing is about 20 kHz, although this is especially true for children and adults tend to lose their high ranking in time and between 15 and 17 kHz is typical of a middle aged man. The upper end of the audible range of a dog about 45 kHz, while a cat is 64 kHz. It is believed that the wild ancestors of dogs and cats have developed this range of superior court to hear high-frequency sounds of your favorite, small rodents made attack. Most dog whistle frequency is in the range of 23 to frequency 54 kHz, so that they are above the range of human hearing, although some set in the audible range.
To the human ear, a dog whistle, the low whistle. The advantage of the dog whistle is that it creates a disturbing noises happen to the people a normal pipe, so it can be used without making disturbing them or the control animals spectators. Some dog whistles have adjustable sliders to active control of the frequency generated. Trainers can only use pipe to get your dog’s attention, or inflict pain for the purpose of behavior modification.
Also supplied lungs whistles, there are also donors electronic devices that emit ultrasonic dogs across the piezoelectric transmitter. The address range is sometimes associated with the detection circuits of the cortex in an effort barking behavior is combined. This type of pipe can also be used to the ultrasonic required to determine the range of hearing for the individual and for physics demonstrations,