scope:

This International Standard specifies a method of measuring and calibrating the photoelectric output factor of single channel analogue photographic-type audio-level test films in all gauges, using a calibrating sound reproducer. It is applicable to both variable area- and variable density-type sound records with a silver audio track.

It also specifies the performance of a calibrating audio reproducer.

Calibrated audio-level test films are employed to measure the precise output level of photographic sound reproducers and the photoelectric output factor of different sound records. They are also employed to establish a reference level on a standard program level meter, should that be appropriate for the installation in use.