A-weighted filter

A-weighted filters are often used in sound measurements and in signal-to-noise measurements in audio engineering. In these types of measurement, standards such as DIN, IEC, CCIR, and IHF are used. Such filters correct the range to be measured in accordance with the response of the human ear. The sensitivity of the average human ear is greatest at about 3 kHz: below and ab ave this frequency, it drops rapidly. The response of an A-weighted filter peaks at around 3 kHz and has unity gain at 1 kHz.