Dog Whistle - High Frequency Generator easy to use app. Dog Whistle produces a high frequency sound. So Dog Whistle doesn't make a sound for humans, but it's loud for dogs, so it's great for dog training, stopping dogs from barking and teaching tricks. Dog Whistle can make high frequency sounds anywhere in the 22,000 Hz to 25,000 Hz range. Dog Whistle helps with human-dog communication and helps your dog understand what you're trying to say.