3C20.10 - Range of Hearing for the Human Ear

Code Number:
Demo Title:
Range of Hearing for the Human Ear
Audible Frequency Range of the Human Ear
Area of Study:
Acoustics, Biology
Wave generator, Amplifier, Speaker (large), Microphone, Tektronix 2235 oscilloscope, Stereo Preamp, Decibel Meter (Radio Shack), Frequency Meter (If Needed).

Video Credit: Jonathan M. Sullivan-Wood.

See also 3C20.10 in Chemistry and Physics of Everyday Experience.

Plug the generator into the auxiliary input of the amplifier and attach a speaker. Plug the microphone into the preamp and the preamp into the oscilloscope. Use the oscilloscope to show that there is sound produced in the inaudible range. The decibel meter may be used in place of the oscilloscope setup to show that there is still damaging levels of sound produced (Infrasound etc.) in the inaudible ranges.

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