MMRanch wrote on Yesterday at 19:30:45:blod wrote that , but I like the idea of it ! 
so if my horn is 110 db then how far is it louder than a car radio of a teenager ? Sound intensity follows the inverse square law.
That means that at double the distance, sound intensity drops to 1/4 of what it was at closer distance. This simple physical fact is why the concept "loud pipes save lives" is an illusion. Loudness is massively related to proximity.
Let's say that the horn's 110 db rating was assigned at 1/2 meter.
At 1 meter from the horn, twice the distance, the rider experiences 1/4 the intensity, that's down 6 db, which is 104 db, still enough to damage his hearing.
At 8 meters away, (~25 ft) the teenager experiences the sound of your horn reduced in intensity by 16 times, or -12 db, which is 98 db. It's loud, but their radio is louder, especially if the windows are rolled up, because the car's enclosure will cut about 6db or more.
Each party is satisfied, mission accomplished, because as THEY experience the sounds, theirs is louder. And, each is well on their way to deafness. The irony is, that as they lose their hearing, those immature, selfish people will need their sound to get LOUDER, to get the same sensation.
Meanwhile, the rest of the world gets to experience the additive nature of sound pollution.