IEC 60268-9 Ed. 1.0 b:1977, Sound system equipment. Part 9: Artificial reverberation, time delay and frequency shift equipment

Applies to devices intended to give reverberation, time delay or frequency shift to signals of an acoustical origin. It covers the types of devices commonly employed to achieve special effects on sound recording, broadcasting and public-address systems. Provides details of the special characteristics and corresponding methods of measurement to be used for artificial reverberation, time delay and frequency shift equipment.