It is possible, in fact simple, to build a device that can jam speech.

It turns out that there is a known psychological phenomenon that sort of disrupts your brain and prevents you from talking. When your words are relayed back to you with a tiny delay, your brain just sort of shuts down and you can’t talk. It’s painless, but disruptive (and I’d imagine confusing). The technology is almost too simple, more or less just a microphone and speaker. Luckily, the article provides a simple way to defeat the device:

Sadly, they report that it has no effect on meaningless sound sequences such as “aaaaarghhh”.

So the question is, when would the device be useful? The obvious suggestion is in a library or church or even in a meeting or something, when you need someone to shut up. But, even though it is painless, it still seems unnecessarily aggressive. You have to target the person you want to stop from talking, and that person has to be rude enough in the first place that they won’t stop talking even though you ask them to. So we’re already talking about a showdown between two people who are resorting to some low down measures. I don’t think you can force someone to be quiet. Even if you prevented them from talking, I’m sure the talker can find other ways to be disruptive. And if they’re already trying to be disruptive, they’re not going to calm down because you physically forced them to stop talking, that’s for sure. The gun doesn’t prevent them from slamming a book down on a table repeatedly.

So what good is it? I suspect it is no good, and it would just be a funny party trick. On the other hand, if Sara could get her hands on it, I think our house would be a lot quieter. Evie and I would have to find something else to do with our time.