Equipping an electronic cinema with the Dolby Digital system
V.A. Ginzburg, K.V. Neverovsky (NIKFI - Cine&Photo Research Institute)
The sound reproduction system of an electronic cinema is based on the same system used in the usual cinema that is provided with the equipment to reproduce film digital sound tracks recorded according to the Dolby Digital system. This system has six, and the Dolby Digital Surround EX system has seven reproducing channels: L, C, R, LS, RS, BS (BLS, BRS), SW. The sound reproduction system should produce the necessary sound pressure levels and the electroacoustic frequency characteristics according to the ISO 2969 standard.
To equalize the electroacoustic frequency characteristics, one can make use of a sound processor, like the Dolby СР 650 film processor.
Analogue signals of eight reproduction channels are produced by the DMA-8 Dolby adapter that has every possible digital inputs and decodes E digital signals encoded according to the PCM, AC-3 or DOLBY systems.
Certainly, Digital Cinema potentially enables more sound reproduction channels than the film sound recording system does. However, realization of this potential will be hindered by the problem of compatibility of an electronic film sound system with that of a conventional cinema.
