This standard specifies the electro-acoustic frequency response characteristics of the full sound reproduction (or monitoring) system for 35mm film optical soundtracks. This standard applies to the main sound channel systems of mixed recording studios, standard projection rooms and indoor cinemas for movies. GB/T 13157-1991 Electro-acoustic frequency response characteristics of sound reproduction for 35mm film optical soundtracks GB/T13157-1991 Standard download decompression password: www.bzxz.net
This standard specifies the electro-acoustic frequency response characteristics of the full sound reproduction (or monitoring) system for 35mm film optical soundtracks. This standard applies to the main sound channel systems of mixed recording studios, standard projection rooms and indoor cinemas for movies.

National Standard of the People's Republic of China
Frequency response characteristics of all electro-acoustic frequency response for reproduction of 35 mm optical sound track.-Reproductinn chararterlsticsGE/F13157-91
This standard adopts the international standards [S07831-1986A-ring frequency response characteristics of reproduction of 35 mm optical sound track of film and 1S02969-19876B-ring electro-acoustic frequency response characteristics and measurement in film recording control room and indoor cinema]. 1 Subject content and scope of application
This standard specifies the electro-acoustic frequency response characteristics of the full reproduction (or monitoring) system of 35 mm optical sound track of film. This standard is applicable to the sound channel system of the mixed recording room, standard projection room and indoor cinema for film. 2 Terminology
2.1 Full sound reproduction system The entire electro-acoustic system used to restore the sound of a film to the sound of the production site in a film mixing recording, standard projection room, and indoor theater. It is usually divided into two parts: A-chain and B-chain. As shown in Figure 1,
2.2 A-chain Achain
Preamplifier and
Its compensation networkwww.bzxz.net
Figure 1 Schematic diagram of full sound reproduction system
The first half of the full sound reproduction system is from the sound transducer device through the preamplifier (including the A-chain compensation network) to the input end of the main attenuator.
2.3 B-chain B-chain
The second half of the full sound reproduction system is from the upper attenuator input end (including the B-chain equalizer, etc.) through the power amplifier, distribution network, and B-chain to the sound field of the listening point or listening area. 2.4 Academy characteristic The electric response characteristic of the loudspeaker input port specified by the Academy of Motion Picture Arts and Sciences for the optical soundtrack reproduction system of movies. 2.5 Pre-compensated optical soundtrack Pre-emphasis Directional soundtrack Conventional optical soundtrack, also known as pre-compensated optical soundtrack. It uses the "" curve in this standard as the B-ring characteristic. It is an optical soundtrack that is used to reproduce sound under the conditions of de-compensation or academy characteristics. 2.6 Wide range soundtrack Wide range sound lrack is a kind of movie soundtrack without pre-compensation. It uses the "x" mountain line specified in this standard as the B-ring characteristic and reproduces the sound under the condition that compensation cannot be performed. Generally, noise reduction processing is added during recording and reproduction. 2.7 Electro-acoustic frequency response clcctroacousticresponsc The frequency response characteristics of the sound pressure level at a specified point in the B-ring sound field through the eight rings within a given frequency range relative to the sound pressure level at that point by any reference sequence:
3 Electro-acoustic frequency response characteristics
There are two specifications for the optical soundtrack of Chinese films: one is the conventional optical track, and the other is the conventional optical track. It is a broadband optical soundtrack. The frequency response characteristics of the two when reproducing sound are very different, and they need to be regulated separately. 3.1 The A-ring and B-ring characteristics of the broadband optical soundtrack are shown in Table 1 and Figure 2. Its B-ring characteristic is called the \n\ characteristic (or curve). 3.2 The A-ring and B-ring characteristics of the broadband optical soundtrack are shown in Table 2 and Figure 3, and its B-ring characteristic is called the "characteristic (or curve). Table 1 A-ring and B-ring characteristics of conventional optical soundtrack Color response
Center frequency,
"n\ characteristic
de
Center frequency, Hz
GB/T 1315791
A and I ring characteristics of conventional optical soundtracks Notes
A and I ring characteristics of wideband optical soundtracks A
*x\ characteristics
.-1. 0
Center frequency, Hz
GB/T 1315791
Continued Table 2
*x\ characteristics
Figure 3 A and B ring characteristics of wideband optical soundtracks 3.3 A ring characteristics of conventional optical soundtracks in theaters with B ring\ characteristics: 2000Hz
In order to ensure the normal reproduction conditions of conventional optical soundtracks, the difference between the two different B ring characteristics (\n\ and \x\) and the A ring characteristics required for conventional optical soundtracks given in the second column of Table 1 should be combined as correction characteristics. This correction is usually added to the narrower and more easily adjusted A ring. Therefore, when a conventional optical soundtrack film is shown in a theater with \x\ characteristics, its A characteristics (with B characteristics) are shown in Table 3 and Figure 4.
Table 3 A characteristics (with B characteristics) of conventional optical soundtracks in a theater with "x\ characteristics"
Center frequency, Hz
"x\ characteristics
w.bzsoso.coCenter frequency, Hz
. 6. 5
CB/T 13157---91
Continued Table 3
"x\ characteristics
20000H2
GB/T 13157.—91
Appendix A
Total frequency response characteristics of optical soundtrack restoration
(Supplement)
The total characteristics of the (A+B) loop of conventional optical soundtrack and broadband optical soundtrack are shown in Table A1 and Figures A1 to A3. Table A1 Total characteristics of the (A+B) loop of optical soundtrack restoration Frequency response
Center frequency, Hz
Total characteristics of conventional optical soundtrack restoration, dB at "n\characteristic color theater
at "x\characteristic theater
Total characteristics of high-band optical soundtrack restoration dB at "\characteristic theater
.de
GB/T 13157—-91
25 GA)
Total characteristics of conventional optical soundtrack restoration at \n" special theater 160
20 00 Hz
20000 Hz
.dE
Additional Notes:
GB/T13157:91
General Characteristics of Broadband Optical Soundtrack Reproduction
This standard is proposed by the Ministry of Radio, Film and Television of the People's Republic of China. This standard is under the jurisdiction of the China Film Science and Technology Research Institute of the Ministry of Radio, Film and Television. This standard is drafted by the China Film Science and Technology Research Institute of the Ministry of Radio, Film and Television. 5000
1000
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