Clever young people in the UK have turned this noise (which is also used as a deterrent in some stores) into a ringtone so they can fool teachers.
US students long ago learned to put their phones on vibrate to do much the same thing. I suspect it is the thrill of 10-15 students simultaneously getting a text message while in class as the teacher drones obliviously on that makes it worth the effort.
You can take the test yourself but you will likely need a teenager around to tell you what the noise sounds like. To be honest, if I concentrated quite hard on listening while in a quiet room, I think I heard a faint buzzing. In a normal situation, however, I am sure I would not even notice it.
- NB: This DOES NOT mean my ears are old, by the way. They are "mature" ears.
Created by Train Horns