Hearing High-Pitched Sounds
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Sounds are caused by vibrating matter, such as the vibrating strings in a violin, or vibrating air in a flute. Sounds can be high-pitched, like a whistle, or low pitched, like thunder. The pitch is caused by the frequency of the vibration. The faster the object vibrates, the "higher" the frequency (and pitch).
For example: Violins, have short, tight strings that vibrate rapidly (high pitch).
Play the sample below to hear a violin.
For example: Violins, have short, tight strings that vibrate rapidly (high pitch).
Play the sample below to hear a violin.
A cello or bass has long strings that vibrate more slowly (low pitch).
Play the samples below to hear a cello and an upright bass.
Play the samples below to hear a cello and an upright bass.
The frequency of a vibration is measured in units called Hertz. One hertz is one vibration per second. The lowest frequency a human can hear is about 20 hertz. The musical note called "middle C" is approximately 262 hertz. When a person plays middle C on the piano, a little hammer strikes a string, and the string vibrates 262 times per second.
Play the sample below to hear middle C on a piano.
Play the sample below to hear middle C on a piano.
If there are 1,000 vibrations per second, that is called 1 kilohertz (1 kHz). Humans can sometimes hear sounds that are over 20 kHz (20,000 hertz)!
Directions: Below is a series of high-frequency tones. The tones range from 3 kilohertz to 23 kilohertz. Starting with 3 kHz, play each tone in order until you reach a sound you can't hear. How many kHz can you hear? Test the people you live with as well. Do you see a relationship between age and hearing ability?
Using the paper that was handed out in class, and the files below, test as many people as you can!
Using the paper that was handed out in class, and the files below, test as many people as you can!