Specifies design, construction and marking, and a range of electrical and mechanical performance requirements for filters for incorporation in sets used in analyzing, as a function of frequency, a broad-band electrical signal in acoustical measurement work. It applies to filters of the passive or active type, including amplifier elements such as electronic valves and transistors. Preferred nominal mid-band frequencies of the pass-band are tabulated, and tolerance curves are given for the response of filters plotted in relation to attenuation for nominal insertion loss and frequency.