How to Make Infrasound

Subwoofer speakers reproduce infrasound waves you feel, not hear.
••• Jupiterimages/ Images

The ears of a healthy young adult hear frequencies in the range of 20 to 20,000 Hz. While you cannot perceive sounds with higher frequencies, you can feel those with lower frequencies. Instruments such as bass drums and phenomena like explosions and thunder produce inaudible low frequencies, called infrasound, in addition to those you hear. Subwoofers are speakers designed to reproduce these frequencies, adding realism to movies, video games and other media. By connecting a variable-frequency sine-wave oscillator to a self-amplified subwoofer, you can produce infrasound.

    Turn on the subwoofer and oscillator. Turn the oscillator’s output amplitude control all the way down. Adjust the oscillator’s frequency to 10 Hz. Set the subwoofer’s output knob to its minimum.

    Attach the BNC female connector to the BNC male on the oscillator. Connect the RCA male plug to an RCA input on the subwoofer.

    Adjust the subwoofer’s output to about one-quarter to one-half its maximum.

    Slowly turn up the oscillator’s amplitude. You will begin to feel infrasound vibrations from the subwoofer. Slowly increase the oscillator’s frequency. Notice as you pass roughly 20 Hz, the subwoofer's output changes from vibrations you feel to those you hear as a low-frequency pitch.

    Things You'll Need

    • Signal generator or oscillator
    • Self-amplified subwoofer
    • BNC female to RCA male adapter cable

Related Articles

How to Convert Hertz to Milliseconds
How to Use a Frequency Counter
What Is the Decibel Level of a Jet Plane?
How to Measure the Percent of Ripple on a DC Power...
Piano Science Fair Ideas
How to Tell the Difference Between Male and Female...
How to Use the Bushnell Telescope 78-9512
Types of Light Sensors
How to Make an Electric Stimulator With Speaker Wires
How to Use a Variac
How to Calculate the Duty Cycle of a Frequency
How it Works: Voltage Relay
How to Reduce 12 Volt to 6 Volt
What Is the Difference Between a Bald Eagle & a Golden...
How to Convert Decibel Increase to Percent
Animals That Chirp at Night
Projects for Electrical & Electronics Engineering
Test Your Knowledge on Middle School Science
What Is the Difference Between Rolling & Clap Thunder?

Dont Go!

We Have More Great Sciencing Articles!