Dolby Laboratories CP65 manual Introduction

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INTRODUCTION

This manual contains essential information on the installation and alignment of the CP65 Cinema Sound Processor. The CP65 supersedes the CP55 and is available in three versions:

CP65

The standard configuration, equipped for the reproduction of the following sound formats

•01 Mono–for all optical prints of any vintage with conventional mono optical (“Academy”) sound-tracks.

•04 Dolby Stereo A-type

•05 Dolby Stereo SR

•10 Dolby Stereo Digital-with the addition of an external digital adapter

•60 Non-sync

•Mag / Aux–This format may be programmed in a number of different ways. Possible options include:

•Magnetic sound-tracks without A-type noise reduction.

•Extra sound sources, such as a Magnetic follower/dubber, PA microphone with preamp or a “stereo” synthesizer.

CP65-A

Equipped with A-type noise reduction only. Reproduces the same formats as the standard CP65 with the exception of 05 Dolby Stereo SR.

CP65-300

Equipped with two Cat. No. 300 modules in place of the Cat. No. 350 SR modules. Cat. No. 300 SR/A processors contain both A-type and SR circuits and these additional two channels of A-type along with the channels in the Cat. No. 222 modules are used to decode 70 mm Dolby Stereo magnetic soundtracks (format 42).

About this manual

This manual is intended to be used by individuals who are qualified in the area of cinema sound service. The basic day-to-day operation of the CP65 is covered in the CP65 Operator’s Guide.

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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 Two-channel Noise Slot Card Function Cat. NoReduction Module Channel DecoderContains 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