On trails I use the bike bell. Sometimes people are oblivious as one person said, "I thought it was a bird". And then there are joggers with their headphones who can't hear them.

So when I notice the bike bike bell is not producing any reaction, I sound the 150db Hornit. On trails sometimes you still need to sound the Hornit a few times. In busy streets, it's still useless because of the ambient traffic noise. What sounds loud in the store or your garage is nothing in city traffic.

The AirZounds gets a lot of attention. But still there are the few people who just don't register the sound and still just stand right in front of you oblivious.

I've been thinking of the LoudBicycle Horn but it's expensive.

Loud Bicycle | Car horn for bikes

It's electric and has the same frequencies as the car horn. So when people hear it, whether they are inside their cars or on the trail, it registers to them that there is a car approaching.