Dolby Laboratories CP65 manual Bypass, Setting Room Equalization

Page 40

5-2

B-Chain Alignment Procedures

a. Setting Room Equalization

Step	Action	Indication
No.

1

NORMAL BYPASS

bypass

(switch behind panel)

2

L		C		R
CINEMA EQUALIZER MODULE CAT. No. 64B Dolby Laboratories Inc. San Francisco and London.		CINEMA EQUALIZER MODULE CAT. No. 64B Dolby Laboratories Inc. San Francisco and London.		CINEMA EQUALIZER MODULE CAT. No. 64B Dolby Laboratories Inc. San Francisco and London.

3

5-3

B-Chain Alignment Procedures

a. Setting Room Equalization

Notes

Open the front panel and place the NORMAL/BYPASS switch in the BYPASS position so power is removed from the Cat. No. 64 Equalizer modules and the loudspeakers are protected. The BYPASS LED should be flashing.

Use the labels that are furnished with the CP65 to mark the three Equalizer modules as L, C, and R respectively. The labels make it easy to restore the modules to their correct positions after they have been removed.

Remove all of the marked Equalizer modules. Remove the shield cover from each equalizer and verify that all of the equalizer controls are set to the mid-position (12 o’clock). Replace the screws to avoid losing them then plug each of the equalizer modules with its cover removed back into the CP65 in its proper slot.

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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 Smpte Buzz Track Stereo Optical Surround Level Cat. No Jiffy Test Film Cat. No 2 Listen . . . Film Cat. NoSection Initial SET-UP and Installation Voltage Acceptable Setting Voltage Range Fuse Type Next, check the jumpers in the following locations Cat. No , Power Supply Module Cat. No , B-Chain CardCat. No , Control Logic Card J2 NON-SYNCCP65 Backplane Standard CP65 or CP65ACP65-300 High Low Subwoofer subwoofer Output output These Modules are Necessary for Bypass Operation Slot Card Function Cat. No Two-channel NoiseReduction Module Channel DecoderContains a semi-regulated power supply with Voltage Setting Fuse Type InternationalIEC Notices HUM Problems Room lighting dimmer controls SCR-TYPEPage Section AN Overview of the Alignment Procedure Aligning the B-ChainPage Page Section Chain Alignment Preliminary Procedures Action IndicationLamp Voltage Optical Preamplifier Adjustments Chain Alignment Procedures Optical Preamplifier Adjustments 222 CAT. no Test Film Oscilloscope Traces Repeat CAT no Repeat 1 →Magnetic Preamplifier Adjustments Magnetic Alignment 100mV Section Chain Alignment Setting Room Equalization BypassLoudspeakers and Crossovers Amplifiers GeneralChain Alignment Procedures OffRepeat ActionChain Alignment Procedures Setting Room Equalization Do not adjust Paul Setting Room Equalization b. Adjusting L,C,R Gain 14 → 21 R 14 →Setting Mono Gain 79 dBCChain Alignment Procedures Subwoofer Alignment Cat. No 90 dBC 85 dBCFrom Step NoSelect format 04 Dolby Stereo A-Type Same AS 441Surround Equalization Alignment Cat. No Surround Equalization Alignment Cat. No Notes Cat. No 441Desired 88 dBC Bypass Thumbwheel Switch Adjustment of Surround DelayMsec Setting Chain Alignment Procedures Adjustment of Bypass Gain Xx dBCFrom Xx dBC -3 dB Yy dBCAdjustment of Non-sync Gain Press the format 60 non sync switchAuto Freq Adjustment of Mono Gain and Equalization Notes Repeat page 5-20 StepChain Alignment Procedures Final Checks Press the format 04 Dolby Stereo A-type switchSection 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 15V +12B Cat. No +24V +15V+15M Appendix a Checking Phasing of Speakers Appendix B Effect of Changes in Slit Height on Slit Losses Operation Appendix C CP65M Mono InstructionsCat. No a Circuit Description Schematic Cat. No a Appendix D Backplane Connections List Terminal Block TB3Connector J18