Hey David! Generally when we refer to “pups” as a form of endearment — we really mean all dogs! Unless the article is specifically about puppies. I would not recommend the ultrasonic bark prevention tool. It’s best to remember that barking is a form of communication — your dog is saying “this is scary, I’m uncomfortable with this”. Rather than basically tell them to shut up and deal with it, which is basically what an aversive tool like an ultrasonic bark preventer is, it’s best to see what is making them nervous, put plenty of distance between them and the trigger, and work on teaching them that the “scary thing” really isn’t so scary. We have a demo video here: https://www.youtube.com/watch?v=FBXwaAG_JaQ

Now, if you mean an actual dog whistle — those can be good for working on recall with your dog (aka having them come when called). But it would not be appropriate for an on-leash interaction like you are describing.