Simple reversible "UFO noise" killer

You did some good homework from a technical standpoint, but I don't see the benefit of disabling a safety device that protects others. I also disagree with the statement that the Prius is loud. I hope it never happens, but if you hurt someone because they didn't hear you that you have good insurance and can live with yourself.

My neighborhood during the summer has lots of noise, people doing yardwork, mowing, kids playing etc. A car rolling down the road - even with tire and road noise - could easily be missed. In the colder months, kids play and wear ear muffs, so again the possibility is real that they could not hear a car going down the road. This is such a bad idea IMO.

 

Even with engine's running they can be VERY quiet, especially some ambient noise.

 

there are many gas cars that are extremely quiet, yet aren't forced to wear a bell.

if ambient boise is loud, no one is going to hear the bell