<P> To human ears, a dog whistle makes only a quiet hissing sound . The advantage of the dog whistle is that it doesn't produce a loud irritating noise for humans that a normal whistle would produce, so it can be used to train or command animals without disturbing nearby people . Some dog whistles have adjustable sliders for active control of the frequency produced . Trainers may use the whistle simply to gather a dog's attention, or to inflict pain for the purpose of behaviour modification . </P> <P> In addition to lung - powered whistles, there are also electronic dog whistle devices that emit ultrasonic sound via piezoelectric emitters . The electronic variety are sometimes coupled with bark - detection circuits in an effort to curb barking behaviour . This kind of whistle can also be used to determine the hearing range for people and for physics demonstrations requiring ultrasonic sounds . </P>

What does a dog whistle do to a dog