We often get asked what is the difference between and audible bird repeller and an ultrasonic bird repeller?
To put it simply, “audbile sound” means that the noise the bird repeller produces can be hear by humans as well as birds. Ultrasonic sound is outside of the human hearing range and so it cannot be heard by humans.
Ultrasonic sound is so high pitched that only birds can hear it. They find it anonoying and so want to leave the area. Its not harmful, just annoying. And very effective!