Editing Weighting filter (section)

=== Sound ===
Sound has three basic components, the [[wavelength]], [[frequency]], and [[Speed of sound|speed]]. In sound measurement, we measure the loudness of the sound in [[decibel]]s (dB). Decibels are [[logarithmic scale|logarithmic]] with 0&nbsp;[[Dbx (noise reduction)|dB]] as the reference.<ref name="OSHA"/> There are also a range of frequencies that sounds can have. Frequency is the number of times a sine wave repeats itself in a second.<ref name=":2"/> Normal [[auditory system]]s can usually hear between 20 and 20,000&nbsp;Hz.<ref name=":2"/> When we measure sound, the measurement instrument takes the incoming auditory signal and analyzes it for these different features. Weighting filters in these instruments then filter out certain frequencies and decibel levels depending on the filter. A weighted filters are most similar to natural human hearing. This allows the sound level meter to determine what decibel level the incoming sound would likely be for a normal hearing human's auditory system.