Sound transmission is indicated in two ways; frequency and intensity.
Sound frequency is a measure of the number of sound waves, or vibrations per second, that reach the human ear within a given period of time. One vibration is called a hertz (Hz). The human ear typically has a range of 16 to 20,000 Hz. Our ears translate sound frequency into pitch, which can be high or low depending on the frequency, or hertz, level. The lower the hertz level, the lower the pitch; the higher the hertz level, the higher the pitch.
Sound intensity, or volume, is measured in decibels (dB) - and clearly is the most desirable to control. Below are typical dBA levels of common sounds and how the change in dB changes the perception of loudness.
