Shh… Don’t Tell the Golden Ears!
Mosquito is a 17 kHz buzz designed to be used outside storefronts to annoy "anti-social" youth. I swear, this sounds like the 50's. I half expected their marketing literature to be filled with pictures of little Fonzies with cigarettes rolled up in their sleeves, hanging out on a set of steps. Are kids really this much of a problem? Adults 40+ tend to suffer from presbycusis (basically age related hearing loss) and generally can't hear the sound.
Kids picked up on the buzz and turned it against the adults that engineered it. Now, they use it for a ring tone on their phone that can be used in classrooms and other locales where cell phones are supposed to be muted or turned off. In an act of extreme capitalism at its finest, the creators of the sound now offer the "official" Mosquito ringtone on their site (yes they still sell the "deterrent" version).
So the real question is: What exactly are all those "super" tweeters for again? In order to really enjoy them to the fullest; you need to be in high school. And how many high schoolers have a couple of grand for an add-on tweeter anyhow?