Dolby Laboratories CP65 manual Next, check the jumpers in the following locations

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STEP 9 Next, check the jumpers in the following locations:

Cat. No. 441 Surround Equalization, Subwoofer and SR•D Interface Card (if fitted).

Mono Stereo

50 Hz

100 Hz

J4

Optical Subwoofer

Crossover Frequency

		auto
		subwoofer
J3	Surround	off
J3	Surround

Output Level

Range

J1

Low

Low High

High

Subwoofer

J2 Level Range

Cat. No. 441

The Cat. No. 441 has four jumpers that are used to configure the card to suit the installation in which it is used.

J1 Right Surround output level sets the output gain range for the right surround channel. J1 is set at the factory for a power amplifier input sensitivity of between 90 mV and 1.23

V.If the power amplifiers used in the installation are very sensitive (10 mV to 100 mV input sensitivity), it may be necessary to move this jumper to the low output position.

J2 Subwoofer output level control sets the output gain range for the subwoofer channels. J2 is set at the factory for a power amplifier input sensitivity of between 90 mV and 1.23

V.If the power amplifiers used in the installation are very sensitive (10 mV to 100 mV input sensitivity), it may be necessary to move this jumper to the low output position.

J3 Surround Mono / Stereo selects stereo or mono surround operation. Set J3 to the Stereo position if your cinema is equipped with separate power amplifiers and speaker wiring for left and right surrounds. Note that stereo surround signals are only available in format 10 Dolby Stereo digital. Install this jumper in the stereo or mono position according to your installation.

J4 Subwoofer upper frequency limit sets upper frequency limit of the subwoofer channel in optical or non-sync to either 50 or 100 Hz. The recommended setting of this jumper depends on the type of screen speakers in your cinema.

If you have the older horn-loaded type of speaker (such as Altec A-4), the jumper should be set for 100 Hz and the equalization for the screen speakers rolled off below this frequency. These settings will remove frequencies from the screen speakers that they cannot gracefully reproduce at full power and send them to the subwoofer which is better able to handle them.

If you have the newer direct radiator type of screen speakers, set J4 to the 50 Hz position and adjust the equalization of the screen speakers to roll off below that frequency.

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Contents Model CP65 Cinema Processor Dolby Laboratories Inc Headquarters Table of Contents Section Reference Block Diagrams Introduction Page Section Equipment Required Jiffy Test Film Cat. No 2 Listen . . . Film Cat. No Smpte Buzz Track Stereo Optical Surround Level Cat. NoSection Initial SET-UP and Installation Voltage Acceptable Setting Voltage Range Fuse Type Next, check the jumpers in the following locations Cat. No , B-Chain Card Cat. No , Power Supply ModuleJ2 NON-SYNC Cat. No , Control Logic CardStandard CP65 or CP65A CP65 BackplaneCP65-300 High Low Subwoofer subwoofer Output output These Modules are Necessary for Bypass Operation Channel Decoder Slot Card Function Cat. NoTwo-channel Noise Reduction ModuleContains a semi-regulated power supply with International Voltage Setting Fuse TypeIEC Notices Room lighting dimmer controls SCR-TYPE HUM ProblemsPage Aligning the B-Chain Section AN Overview of the Alignment ProcedurePage Page Section Chain Alignment Action Indication Preliminary ProceduresLamp Voltage Optical Preamplifier Adjustments Chain Alignment Procedures Optical Preamplifier Adjustments 222 CAT. no Test Film Oscilloscope Traces Repeat Repeat 1 → CAT noMagnetic Preamplifier Adjustments Magnetic Alignment 100mV Section Chain Alignment Bypass Setting Room EqualizationLoudspeakers and Crossovers General AmplifiersOff Chain Alignment ProceduresAction RepeatChain Alignment Procedures Setting Room Equalization Do not adjust Paul 14 → 21 R 14 → Setting Room Equalization b. Adjusting L,C,R Gain79 dBC Setting Mono GainChain Alignment Procedures Subwoofer Alignment Cat. No 85 dBC 90 dBCStep No FromSelect format 04 Dolby Stereo A-Type 441 Same ASSurround Equalization Alignment Cat. No Cat. No 441 Surround Equalization Alignment Cat. No NotesDesired 88 dBC Bypass Msec Setting Adjustment of Surround DelayThumbwheel Switch Xx dBC Chain Alignment Procedures Adjustment of Bypass GainXx dBC -3 dB Yy dBC FromPress the format 60 non sync switch Adjustment of Non-sync GainAuto Freq Repeat page 5-20 Step Adjustment of Mono Gain and Equalization NotesPress the format 04 Dolby Stereo A-type switch Chain Alignment Procedures Final ChecksSection Reference Diagrams Cat. No Dual Noise Reduction Module Inputs Cat. No Optical Bass Extension and Surround Equalizer Card Cat. No B-Chain Facilities Card Cat. No Power Supply Card Cat. No Transformer Module Inputs Cat. No Control Logic Card +15M Cat. No +24V +15V15V +12B Appendix a Checking Phasing of Speakers Appendix B Effect of Changes in Slit Height on Slit Losses Cat. No a Circuit Description Appendix C CP65M Mono InstructionsOperation Schematic Cat. No a Terminal Block TB3 Appendix D Backplane Connections ListConnector J18