The frequency level of a sound is determined by the vibration rate of the sound waves. The faster the waves vibrate, the higher the frequency. Conversely, the slower the waves vibrate, the lower the frequency.
The human ear can hear sounds with frequencies between about 20 Hz and 20,000 Hz. Sounds below 20 Hz are considered to be infrasound, while sounds above 20,000 Hz are considered to be ultrasound.
The frequency level of a sound can affect how it is perceived. For example, high-frequency sounds can be perceived as being shrill or piercing, while low-frequency sounds can be perceived as being deep or rumbling.
The frequency level of a sound can also be used to determine its wavelength. The wavelength of a sound wave is the distance between two successive peaks or troughs of the wave. The longer the wavelength, the lower the frequency. Conversely, the shorter the wavelength, the higher the frequency.
