The sound does make dogs back off. I carry a walking stick and a stun gun when I walk. Just in case.
My sister walks her dogs everyday on a leash, other people have their dogs there on a leash. That’s how it should be. The electrical shock (tase) shouldn’t be necessary but be damned if I want a dog biting me. People need to be responsible for their pets behavior. I carry a 9mm but I don’t want to use it.