As you get older, the hearing process (sound waves travel into your ear, hit your eardrum, and vibrate three tiny bones, transmitting sound into the inner ear) stops working as well, making certain high frequencies hard or impossible to hear.
This can happen as early as the time you turn 25.
Let's see how well you hear and if you hear your age.
Let's get started. Use this to adjust your speakers to a comfortable volume. Everyone should be able to hear this.
Moving on: This is 14,400 hertz. This should be difficult for anyone over 25 to hear. There should be a slight click when the sound begins.
Now this is the sound that separates the men from the boys — literally. At 17,400 hertz, this sound is often used to drive teenagers away.
Finally, at 18,000 hertz, this sound should be hard to hear no matter what age you are.
If you couldn't hear anything for the last two sounds: 1) You're old, and 2) Here they are together, playing at the same time.