In my state speeding through construction when lights are flashing meaning persons actually there working will get you a $500 fine. In 99% of the zones at least one cop is there drawing some extra cash which is fine. That should suffice. A sound cannon can cause the offending driver and others to loose complete control of self and vehicle.
Yeah, this might create more problems than it solves. I was mainly trying to express support for taking the speeding problem seriously. Also, I thought that the article was a bit hyperbolic in that it left the impression that the device would be used as a weapon, rather than as a communications device. (Albeit, a very loud, perhaps dangerous-to-use-with-moving-traffic type of communications device.)
BTW, police enforcement in construction zones is rare here — especially if only the survey crew is working. It can be pretty scarey, when you have to set up in the middle of a busy highway.