I received my Hornit bicycle horn today, and damn, is the thing ever loud. Painfully loud, in fact. As it needs to be; there’s a layer of glass and steel and a fog of oblivion it needs to penetrate.
It’s already been installed, with the trigger button in the somewhat odd location of the underside of the left side of the handlebar grips of each bike (I bought extra trigger buttons and mounts, so I can shift the horn to the bike I am using). Reason for putting it there is it’s easy to hit the button with my thumb while using the rest of my fingers for braking.
I will definitely be braking at least 90% of the time I use the thing. A horn is not a substitute for slowing down to avoid a crash; it’s an adjunct. It’s a way of announcing “Wake up! I am here! Pay attention!”. If push comes to shove, a car will win any disagreement with a bicycle, and decisively. The differences in mass and shielding are just too great.
But, if more bicyclists had loud horns and used them to blast oblivious drivers of motor vehicles, it would have the positive effect of getting more drivers to watch for vehicles other than large, motorized one; that is the real virtue of equipping bicycles with loud horns.