Can you hear this?

Oct. 31, 2007

It’s well known in the annals of electric engineering that when the middle-aged men at RCA were developing television, they needed a sound they could use to test the equipment. They chose something in the high frequency range that they could not hear but would show up on their oscilloscopes. They were shocked when television sets came on the market and people could hear the sounds that they could not. Young people could hear it, but not old engineers.
Have you heard that high pitched sound lately? I haven’t in years. It turns out that as we age, we lose the high range of frequencies. For older people who begin to lose their hearing, it becomes more and more difficult to understand women’s voices. When I went to the movies recently, I could not understand one word spoken by a new female character with a high-pitched, soft voice.
This may explain why old women complain about their husbands not listening to them. The husbands don’t hear their wives’ voices.
This universal phenomenon of hearing loss was taken advantage of by engineers in England in response to a complaint by a shopkeeper who wanted to shoo teenagers away from his store. They hung around and intimidated his customers. By broadcasting a very loud, irritating noise like the buzz of a mosquito, the store owner made the sidewalk outside intolerable. The kids went away, but the adult customers didn’t hear the noise.
It’s a bit like my neighbor’s dog. When his master plays the organ, the high pitches hurt the dog’s ears and the poor critter cries in agony.
That’s one way to make sure only adults will enter your liquor store, fake ID or not. If one of those adults is carrying a baby, don’t be surprised if the baby starts to cry because of the nasty noise it can hear but you can’t.
The fact that teenagers can hear sounds that most adults cannot has been used to a new advantage in the classroom. It turns the tables on the shopkeeper who used that frequency to chase teenagers away. David Herzka, a Roslyn High School freshman, found out about the high frequency sound and downloaded it off the Internet to his cell phone. Using it as a ring tone only youngsters could hear, he gave it to some friends.
The upshot was that students taking their cell phones to school could call each other and text message to friends without the teachers hearing the calls.
Combining that ability with the other cell phone features produced this ploy: taking a test? Don’t know the answer to a multiple choice question? Station a smart pal outside the classroom. When you get to a question you don’t know the answer to, call your friend on your cell, photograph the question, and wait for the text message with the right answer.
The kids got away with it until a teacher who was only 28 years old and hadn’t yet lost her upper range hearing noticed the calls coming in and demanded to know who was using their cell phone. The jig was up.
One blogger says that the solution is to hire younger teachers.
No wonder teachers forbid the use of cell phones in class. They’re not only a distraction, but a new way to cheat. It seems that no matter what new technology is developed, someone will find a nefarious use for it.
Visit the web site www.hu.mtu.edu/~hlsachs where you can listen to two stories, read a third, read reviews, and find links to the publishers of Harley Sachs’ books.