Range of Hearing
Safety Warnings
Warning: Hearing Protection
Purpose
Demonstrates the range of human hearing by sweeping from 20 kHz downward. Students raise their hands when they hear the tone, vividly showing that high-frequency hearing declines with age — the instructor typically can't hear what students can.
Figure 1:
Complete acoustic measurement system showing signal generators for frequency control, oscilloscope for waveform monitoring, and powered monitor speaker for audio output. The microphone (upper right) can be used to verify sound output on the oscilloscope.