Dolby Laboratories 737 2.2.2 Mon Out , 2.2.3 DC Out

Model 737 Soundtrack Loudness Meter - Leq(m) Operation and Features

2-4

2.2.2 Mon Out

Figure 2-5 Mon and DC Out, and power/control connector

Mon Out is an unbalanced output which, in calibration mode, provides an unweighted

mono mix of channels. In measurement mode, Mon Out carries a mono mix of the outputs

of the weighting filters. Listening to the filtered output can help the mixer find the effect

or equalizer setting that is raising the average above the standard. Mon Out is adjustable

on the front panel from -20 to 0 dBu for Dolby Level so that it can be balanced with the

studio monitor level.

Mon Out uses the following wiring convention:

Table 2-2 Mon Out wiring convention

2.2.3 DC Out

DC Out is an unbalanced output to drive an optional moving coil meter/chart recorder.

Using a 1 mA moving coil meter with a calibrating potentiometer across its terminals

is a useful method to observe measurement trends. DC Out uses the following wiring

convention:

Table 2-3 DC Out wiring convention

1 V is equivalent to 91 Leq(m); the range is 0–1.25 VDC; 0 VDC corresponds to

70 Leq(m); output resistance is 1 kΩ.

Pin Connection

1Chassis

2 Mon signal out

3 Mon signal common

Pin Connection

1Chassis

2 DC out

3 DC return

MonOut DC Out 24Vac

500mA

ACIn ~

ACIn ~

Ref

Gnd

TripOut

TripOut

TripOut

Gnd

Start/ Stop

Model 737

MAIN

Contents

Main Dolby Laboratories Inc Table of Contents List of Figures List of Tables Chapter 1 Introduction Chapter 2 Operation and Features Chapter 3 Cat. No. 448B Input Adapter Board Chapter 4 Specifications Appendix A Background List of Figures List of Tables Chapter 1 Introduction Chapter 2 Operation and Features 2.1 Front Panel Controls 6/4 - 2 channel switch Start Trip Set Cal 2.1.1 6/4 2 Channel Switch 2.1.2 Input Trimpots 2.1.3 Trip Set 2.1.4 Pushbuttons Model 737 Soundtrack Loudness Meter - Leq(m) Operation and Features 2.2 Back Panel Connectors Figure 2-3 Model 737 back panel 2.2.1 Analog Audio Inputs Figure 2-4 Audio input connectors (detail of rear panel) The XLR input connectors for channels 16 use the following wiring convention: 2.2.2 Mon Out 2.2.3 DC Out 2.2.4 Power and Control 2.3 Connection and Calibration 2.3.1 Connecting to an Audio Console 2.3.2 Connecting to a Dolby Cinema Processor 2.3.3 Connecting to a DA10/20 Digital Adapter 2.3.4 Connecting to Non-Dolby Digital Adapters 2.3.5 Connecting to the SDU4 Surround Decoder 2.3.6 Calibration Procedure 2.3.7 Automated Input Adapter Board (Cat. No. 448B) 2.4 Mains Power 2.5 Interface 2.5.1 Grounding Model 737 Soundtrack Loudness Meter - Leq(m) Operation and Features 2-10 2.6 Block diagram Figure 2-6 Model 737 block diagram L/Lt C Ls R/Rt Sub Rs Page Chapter 3 Cat. No. 448B Input Adapter Board 3.1 Introduction 3.2 Logic map Model 737 Soundtrack Loudness Meter - Leq(m) Cat. No. 448B Input Adapter Board 3-2 3.3 Component and Connector Layout x2 (Lt/Rt - opt) CAT. NO. 448B Cat. No. 448B Figure 3-1 Cat. No. 448B Interface Adapter 3.4.3 Alignment 3.5 Dubbing studio Page 3.5.1 Alignment Page Chapter 4 Specifications Temperature and Humidity EMC Limits General Appendix A Background A.1 Loudness A.1.1 The Current Situation Page A.2 How Loud Is a Movie? A.3 Standardizing a Measurement Technique for Soundtrack Loudness A.3.1 Alternative Measurement Indices A.4 Analysis of the Data Page Model 737 Soundtrack Loudness Meter - Leq(m) Background A-8 Figure A-5 Comparison of Leq(m) and peak levels Shine demo 1 (Rach. III) Leq CCIR-weighted Peak Level C-weighted, fast 5.6 dB offset dB A.4.1 Verification of the Data Leq CCIR-weighted Peak Level C-weighted, fast