ITU-R 468 noise weighting

ITU-R 468 (originally defined in CCIR recommendation 468-4, therefore formerly also known as CCIR weighting; sometimes referred to as CCIR-1k) is a standard relating to noise measurement, widely used when measuring noise in audio systems. The standard,[1] now referred to as ITU-R BS.468-4, defines a weighting filter curve, together with a quasi-peak rectifier having special characteristics as defined by specified tone-burst tests. It is currently maintained by the International Telecommunication Union who took it over from the CCIR.

It is used especially in the UK, Europe, and former countries of the British Empire such as Australia and South Africa.[citation needed] It is less well known in the USA where A-weighting has always been used.[2]

M-weighting is a closely related filter, an offset version of the same curve, without the quasi-peak detector.

  1. ^ "RECOMMENDATION ITU-R BS.468-4 - Measurement of audio-frequency noise voltage" (PDF). www.itu.int. International Telecommunication Union. Retrieved 18 October 2016.
  2. ^ "1910.95 - Occupational noise exposure. | Occupational Safety and Health Administration". www.osha.gov. Retrieved 2018-10-28.