Shure DCS 6000 User manual

© 2016 Shure Incorporated
27131341 (Rev. 1)
Discussion and Conferencing
USER GUIDE
DIS-CCU Central Control Unit
DCS 6000 System Mode

2
Table of Contents
Table of Contents 2
Important Product Information 3
Important 3
DIS-CCU Central Control Unit 6
Information in This Manual 6
Overview 7
Features 7
Feature Licenses 8
Purchasing the Feature License File 8
Upgrading Legacy DIS CUs 8
Adding the License to the DIS-CCU 9
Select the System Mode 10
DIS-CCU Hardware Description 11
Rackmounting the CCU 12
Simplified Audio Diagram 12
Menu Navigation 13
Connecting the DCS-LAN Equipment 14
Connecting Microphone Units and DCS-LAN
Components 14
DCS 6000 Cable Requirements 15
Connection Diagrams 17
Power Requirements 21
Installing Large Systems 27
System Set Up 29
Web Interface 29
Language Setting 35
Security 36
Assigning Names and Seat Numbers 37
Audio Settings 39
The Floor Mix 39
Route Microphones to Groups 39
Floor Mix on the Loudspeakers 40
Headphone Channels 40
Audio Source for the Loudspeaker and Headphones 41
Analog Audio Outputs 42
Adding an External Audio Source 43
Adding Ambient Sound 45
Participant Microphone Settings 46
Microphone Operation Modes 46
Replies 48
Number of Active Microphones 49
Interrupt Mode 50
Voice Detection 51
Language Interpretation 52
Wireless Language Distribution 53
Listening to Interpretation 53
Set up Interpretation Channels 53
Interpretation Settings 54
Command Strings for External Controller 55
General Protocol Behavior 55
Voting Control 56
Voting Results 57
Microphone Control 57
Audio Control 60
Voting Commands 62
Troubleshooting 65
Firmware Update 66
Factory Default Reset 66
Diagnostic Report 66
Technical Specifications 67
DCS 6000 System 67
Wiring Details 68
How To Order 69
DIS-CCU 69
PS-CCU Power Supply 70
Pre-Tested Shure Cables 70
Advanced Setup 71
Spare Parts 71

3
Important Product Information
Important
Important Safeguards
1. Read these instructions - All the safety and operating
instructions should be read before the apparatus or
system is operated.
2. Keep these instructions - The important safety
instructions and operating instructions should be
retained for future reference.
3. Follow all warnings - All warnings on the apparatus
and in the operating instructions should be adhered to.
4. Follow all instructions - All instructions for installation
or use/operating should be followed.
5. Do not use this apparatus near water - Do not use
this apparatus in a water or moistures environment - for
example, near a bath tub, wash bowl, kitchen sink, or
laundry tub, in a wet basement, near a swimming pool,
in an unprotected outdoor installation, or any area which
is classified as a wet location.
6. Warning: To reduce the risk of fire or electric shock,
do not expose this apparatus to rain or moisture and
no objects filled with liquids, such as vases, should
be placed on this apparatus.
7. Clean only with dry cloth - Unplug the apparatus from
the outlet before cleaning. Do not use liquid cleaners or
aerosol cleaners.
8. Do not block any ventilation openings. Install in
accordance with the manufacturer’s instructions
- Openings in the enclosure, if any, are provided
for ventilation and to ensure reliable operation of
the apparatus and to protect it from overheating.
These openings must not be blocked or covered.
This apparatus should not be placed in a built-in
installation unless proper ventilation is provided or the
manufacturer’s instructions have been adhered to.
9. Do not install near any heat sources such as
radiators, heat registers, stoves, air ducts, or other
apparatus (including amplifiers) that produce heat.
10. Do not install the unit in a place exposed to direct
sunlight, excessive dust or humidity, mechanical
vibration or shock .
11. To avoid moisture condensations do not install the
unit where the temperature may rise rapidly.
12. Do not defeat the safety purpose of the polarized or
ground-type plug. A polarized plug has two blades with
one wider than the other. A grounding type plug has two
blades and a third grounding prong. The wider blade or
the third prong is provided for your safety. If the provided
plug does not fit into your outlet, consult an electrician
for replacement of the obsolete outlet.
13. Protect the power cord from being walked on
or pinched particularly at plug, convenience
receptacles, and the point where they exit from the
apparatus.
14. Only use attachments/accessories specified by the
manufacturer . Any mounting of the apparatus should
follow the manufacturer’s instructions, and should use a
mounting accessory recommended by the manufacturer.
15. Use only with the cart, stand, tripod, bracket or
table specified by the manufacturer, or sold with the
apparatus.
When a cart is used, use caution
when moving the cart/apparatus
combination to avoid injury from tip-
over - Quick stops, excessive force,
and uneven surfaces may cause the
appliance and cart combination to
overturn.
16. Unplug this apparatus during lighting storms
or when unused for long periods of time . – Not
applicable when special functions are to be maintained,
such as evacuation systems.
17. Refer all servicing to qualified service personnel.
Servicing is required when the apparatus has been
damaged in any way, such as power-supply cord or
plug is damaged, liquid has been spilled or objects
have fallen into the apparatus, the apparatus has
been exposed to rain or moisture, does not operate
normally, or has been dropped.
18. Replacement Parts - When replacement parts are
required, be sure the service technician has used
replacement parts specified by the manufacturer or
having the same characteristics as the original part.
Unauthorized substitutions may result in fire, electric
shock or other hazards.

4
19. Safety Check - Upon completion of any service or
repairs to this apparatus, ask the service technician to
perform safety checks to determine that the apparatus is
in proper operating condition.
20. Overloading - Do not overload outlets and extension
cords as this can result in a risk of fire or electric shock.
21. Power Sources - This apparatus should be operated
only from the type of power source indicated on the
marking label. If you are not sure of the type of power
supply you plan to use, consult your appliance dealer
or local power company. For apparatuses intended to
operate from battery power, or other sources, refer to the
operating instructions.
22. Power Lines - An outdoor system should not be
located in the vicinity of overhead power lines or other
electric light or power circuits, or where it can fall into
such power lines or circuits. When installing an outdoor
system, extreme care should be taken to keep from
touching such power lines or circuits, as contact with
them might be fatal.
23. Object and Liquid Entry - Never push objects of any
kind into this apparatus through openings as they may
touch dangerous voltage points or short-out parts that
could result in a fire or electric shock.
Never spill liquid of any kind on the apparatus. Should
any liquid or solid object fall into the cabinet, unplug the
unit and have it checked by qualified personnel before
operating it further.
Labels
“Lightning Flash Symbol” with the lightning flash
with arrowhead symbol within an equilateral
triangle, is intended to alert the user to the
presence of un-insulated "dangerous voltage"
within the product enclosure that may be of
sufficient magnitude to constitute a risk of
shock to persons.
“Exclamation Point Symbol” with the
exclamation point within an equilateral triangle
is intended to alert the user to the presence
of important operating and maintenance
(servicing) instructions in the literature
accompanying the product.
Note for Power Connections
Check that the voltage of your local power supply is within
the operating voltage of the unit. If a voltage conversion is
required, consult your DIS dealer or qualified personnel.
Set the Power switch to ‘Off’ if it is not used for several
days.
Important: The equipment must be connected to
earth (ground)
The wires in the main lead supplied with the equipment are
colored in accordance with the following codes:
• Green-and-yellow Earth (Ground)
• Blue Neutral
• Brown Live
• The green-and-yellow wire must be connected to the
terminal in the plug marked with the letter E or with the
safety earth symbol or marked with green-and-yellow
color.
• The blue wire must be connected to the terminal marked
with the letter N or marked with black color.
• The brown wire must be connected to the terminal
marked with the letter L or marked with red color.
• For pluggable equipment, the socket-outlet shall
be installed near the equipment and shall be easily
accessible.
Power Disconnect
Apparatuses with or without On/Off switches have power
supplied to the apparatus whenever the power cord is
inserted into the power source; however, the apparatus
is operational only when the On/Off switch is in the On
position. The power cord is the main power disconnect for
all apparatuses.

5
Compliance
This equipment has been tested and found to comply with
the limits of the following for a Class A digital device:
• EN55103-1 (Emission)
• EN55103-2 (Immunity)
• FCC rules part 15, class A (Emission)
• ICES-003 of Industry Canada
• IEC 60065
Warning:
Operation is subject to the following conditions: (1) The
device may not cause harmful interference, and (2) the
device must accept any interference received, including
interference that may cause undesired operation.
These limits are designed to provide reasonable protection
against harmful interference when the equipment is
operated in residential, commercial or light industrial
environments. The equipment generates, uses, and can
radiate radio frequency energy and if not installed and used
in accordance with the user manual it may cause harmful
interference to radio communications.
Operation of this equipment in residential areas is likely
to cause harmful interference in which case the user will
be required to correct the interference at his own expense.
Intentional or unintentional changes or modifications not
expressly approved by the party responsible for compliance
shall not be made. Any such changes or modifications
could void the user’s authority to operate the equipment.
If necessary, the user should consult a dealer or an
experienced radio/ television technician for corrective
action. The user may find the following booklet prepared
by the Federal Communications Commission helpful: "How
to identify and Resolve Radio-TV Interference Problems".
This booklet is available from the U.S. Government
Printing Office, Washington, DC 20402, Stock No.
004-000-00345-4.
Warning: This is a Class A product. In a domestic
environment this product may cause radio
interference in which case the user may be
required to take adequate measures.
Cleaning
To keep the cabinet in original condition, periodically wipe
it down with a soft cloth. Stubborn stains may be removed
with a cloth lightly dampened with a mild detergent solution.
Never use organic solvents such as thinners or abrasive
cleaners since these will damage the cabinet.
Repacking
Save the original shipping box and packing material; they
may be used to ship the unit. For maximum protection, re-
pack the unit as originally packed from the factory.
Warranty
The units are covered by a 24 month warranty against
defects in materials or workmanship.
Certifications
This product meets the Essential Requirements of all
relevant European directives and is eligible for CE marking.
The CE Declaration of Conformity can be obtained from:
www.shure.com/europe/compliance
Authorized European representative:
Shure Europe GmbH
Headquarters Europe, Middle East & Africa
Department: EMEA Approval
Jakob-Dieffenbacher-Str. 12
75031 Eppingen, Germany
Phone: [phone]
Fax: [phone]
Email: [email protected]

6
DIS-CCU Central Control Unit
Information in This Manual
The DIS-CCU operates standard in 5900 mode for use in a DCS 5900 system. By uploading a feature license, the DIS-
CCU can operate in 6000 mode for use in a DCS 6000 system. This manual describes the DIS-CCU when operating in
DCS 6000 mode.
For information on operation with the DDS 5900 Discussion system, consult that manual found on the Shure website.

7
Overview
The DIS-CCU Central Unit (CCU) is the system controller for the DDS 5900 Discussion and DCS 6000 Conference
Systems. The CCU processes a mixture of microphone units, interpretation stations, and loudspeakers, all on the
same network. DIS systems comply with international conference standards, supporting advanced speaker control,
interpretation, voting, and conference management for up to 3,800 participants.
on
ULXD2
Audio Inputs
Audio Outputs
Remote Control
Control of up to 3,8000 conference units
System Hub
The CCU connects external equipment to the DCS 6000 system
Features
When set to DCS 6000 mode, the DIS-CCU has the following features:
• Controls a system of conference units, interpreter stations, channel selectors and voting units.
• Transports secure audio signal with a proprietary codec algorithm
• Provides a web server for advanced control through a browser interface
• Supplies power for up to 50 conference units
• Supports up to 31 interpretation channels for multilingual meetings
• Provides eight audio outputs to send interpretation channels or microphone groups to PA systems, audio mixers, audio
recorders, or a language distribution system
• Provides two audio inputs for connecting wireless microphones, processed audio signals, an emergency broadcast
message (EEM), or music during meeting breaks
• One rack unit (1RU) size installs into a standard 19" rack

8
Feature Licenses
The DIS-CCU operates with both DDS 5900 Discussion and DCS 6000 Conference systems. The CCU includes the DDS
5900 mode as standard, and can operate in DCS 6000 mode after installing a feature license. Additional licenses are
available to add participants and interpretation channels when running a DCS 6000 system.
To use DCS 6000 microphone units, ensure the FL6000 is installed and operating on the DIS-CCU.
Feature Licenses for the DCS 6000 System
Model Feature Description
FL6000 DCS 6000 Conference System mode
FL6000-3800 250 – 3,800 participant seats
FL6000-INT-8 8 interpretation channels
FL6000-INT-16 16 interpretation channels
FL6000-INT-31 31 interpretation channels
Purchasing the Feature License File
Contact your regional Shure sales representative to purchase a feature license file to enable DCS 6000 mode and
expansion features. The features are bundled in a single .xml file generated specifically for the serial number of the
DIS-CCU.
Upgrading Legacy DIS CUs
Shure provides a free upgrade for legacy DIS CUs to add features that are now included as standard with the DIS-CCU.
Contact your local Shure sales representative to obtain the file.
The CU 5905 upgrades to the following features:
• Additional participant web pages (chairman and display-only)
• Input 2 configurable as normal audio input
The CU 6105, CU 6110, CU 6005 and CU 6010 upgrade to the following features:
• Control of up to 250 participants
• Additional participant web pages (chairman and display-only)
• Microphone voice activation (vox)
• Voting
• Audio scrambling for CU 60xx
• Voting control over RS232 for CU 60xx

9
Adding the License to the DIS-CCU
After purchasing the license file, upload it to the unit using the DIS-CCU web interface:
1. Save the license file (.xml extension) to the computer or USB drive.
2. Connect the DIS-CCU and open the web interface. Sign in as the Admin if a password has
been set.
3. Go to the License page (System > License).
License Page without Upgrades
Before the license is loaded to the system, only the DDS 5900 mode is available
4. Select Browse to locate the license file.
5. Select Go to install the file to the DIS-CCU. The unit will reboot.
After Installing the License File
The features are listed at the top of the web page and the mode is selectable for
operation with the DDS 5900 or DCS 6000 system.

10
Select the System Mode
A unit with the DCS 6000 license installed can operate for either DDS 5900 or DCS 6000 system. In 5900 mode, the
additional feature licenses are disabled.
Note: Microphone units cannot be mixed across systems; DDS 5900 microphone units only operate in DDS 5900
system mode, and DCS 6000 units operate in DCS 6000 mode.
Select the system mode:
DIS-CCU Front Panel
From the license page: System > License > Select System
Web Interface
System > License Info > Select [5900 or 6000] System

11
DIS-CCU Hardware Description
Out A Out B Out C Out D
DIS-CCU Central Control Unit
TCP/IP
Out E
A B C D Out F Out G Out H
DIS-CCU Central Unit
Front Panel
① Menu display
A 2x20 character OLED-display enables system
configuration without a computer.
② Navigation Buttons
5-button keypad for configuring the system without a
computer.
③ Power Button
The power button turns on or off the central unit. All
connected DCS-LAN units and power supplies will
automatically power on or off with the CCU.
• Green = powered on
• Red = powered off but connected to power supply
• Off = no power supply is connected to the CCU
Note: System settings are stored and persist through a power cycle.
Back Panel
④ Power Supply Connector
Threaded connector secures to the PS-CCU power supply.
⑤ DCS-LAN Outputs
Four RJ45 jacks are available for connecting the
microphone units, forming the DCS-LAN. The DCS-LAN
chain safely carries digital audio, control data, and power
over the same cable. Use any or all of the four outputs for a
variety of layout configurations.
Important: Only connect DCS-LAN equipment to this output.
⑥ Control Connector (TCP/IP)
The RJ45 connector allows access to the built-in web
application from a computer, or for connection to a control
system like AMX®or Crestron®.
⑦ Audio Outputs
Eight balanced, male XLR connectors for connection to
PA systems, audio mixers, audio recorders, or a language
distribution system.
⑧ Audio Inputs
Two balanced, female XLR connector for adding external
audio equipment to the meeting, such as wireless
microphones, a teleconferencing system, processed audio
signals, an emergency broadcast message (EEM), or
music during meeting breaks. Input gain and volume are
adjust from the CCU front-panel or web application.
⑨ Emergency switch connector
Provides an emergency override signal in the event of
an emergency. When the connected switch is closed, the
audio signal on Input 2 is distributed to all output channels,
overriding all other audio inputs.

12
Rackmounting the CCU
Install the central control unit in a standard 19” rack using the supplied 19” brackets. Remove the screws holding the top
and bottom covers, then attach the brackets to the front of the unit using the same screws.
Important: Use the two 10 mm length self-threading screws closest to the front and the 8 mm length threaded
screw furthest from the front.
The built-in fan draws air in on the left side and exhausts air on the right, and so does not require extra space above or
below for cooling.
Simplified Audio Diagram
DIS-CCU Audio Diagram

13
Menu Navigation
The DIS-CCU provides controls from the front panel for
system setup and configuration. Use the 5-button keypad to
navigate the menu and change settings.
The figure below gives an overview of the menu structure.
• Use arrow buttons to cycle through menu items
• Press enter (center) button to navigate to an editable
field.
• Use up/down buttons to cycle through the available
values
Loudspk. Control
Max. Speakers
Max. Requests
0 to -40 dB, Off
On/Off
Audio In 1-> Loudspk.
Audio In 2-> Loudspk.
On/Off
Auto Off Time 5 to 60 sec
Auto off On/Off
Speak Interrupt Lower, Same, None
0 to 250
Max. Replies
Operation Mode
1.0 to 10.0 sec
Release Time
-12 to 8 dB
Threshold
1 to 8Max. Total Speakers
1 to 8
Max. Deleg. Speakers
Local Hostname
Dynamic/Static
IP Address Mode
dis-ccu
Restore Factory Defaults
MAC Address
Subnet Mask
Default Gateway
IP address
Participant Setup
License Info
FW Release ID
Serial Number
250/3800
Max. Conf. Units
Licensed 4 to 31
Max. Intp. Channels
License Available
6000 Operation
OK/Cancel
Select 5900 System
System
Operation
Voice Detection
LAN Setup
Main Menu
Mic -> Loudspk.
Loudspk. Volume
Auto, Manual, FIFO,
Vox, Auto Reply, Manual
Reply, Vox Reply
xx:xx:xx:xx:xx:xx
xxx.xxx.xxx.xxx
xxx.xxx.xxx.xxx
xxx.xxx.xxx.xxx
x.x.xxx
xxx.xxx.xxx
OK/Cancel
0 to 250
6000 tMode
Audio Out A Volume 0 to -40 dB, Off
On/Off
Menu Overview - DCS 6000 Mode

14
Connecting the DCS-LAN Equipment
Shure offers cables designed specifically for the DIS line of conferencing and discussion equipment. The Shure EC 6001
are high-quality Ethernet cables available various lengths from 0.5 m to 100 m. Each cable has been tested to ensure
reliable system performance. See the accessories section for ordering information on the EC 6001-xx.
Important: Cables and connectors must be shielded for stable system performance. If an installation does not use
Shure EC 6001 cables, they must follow the Cat5e cable requirements.
Connecting Microphone Units and DCS-LAN
Components
Microphone units and DCS-LAN components are connected in sequence (daisy-chain) using the two RJ45 ports on each
unit. The connectors are interchangeable; simply connect the previous unit to one port, and the following unit to the other
port. Always use shielded Cat5e (or higher) cabling for reliable system performance.
A B C D
Central Control Unit
Microphone units
Shielded Cat5e cable
Power, control data, and audio are transported from one unit to the next over the same shielded Cat5e cable.
To protect the equipment, ensure that the central control unit (CCU) is always off when connecting or disconnecting the
microphone units. Use any of the four chain outputs (A, B, C, and/or D) for connecting DCS-LAN components.
1. Power off the CCU to protect the equipment during set up.
2. Connect a chain output on the CCU to the first microphone unit with the shielded Cat5e cable.
3. Connect the rest of the microphone units in sequence, using the RJ45 jacks on the bottom of each unit.
4. Turn on the CCU by pressing the power button. The microphone units will power on. The unit is stable once the control
button LEDs stop flashing.
Note: Do not turn off CCU power until the system has stabilized

15
DCS 6000 Cable Requirements
Cat5e Cable Requirements
Type Cat5e (or higher) twisted pair
Shielding F/UTP or U/FTP
Connector Shielded RJ45
Weight AWG 24
Maximum Cable Length •DIS-CCU only: 200 m
•DIS-CCU with repeater units: 680 m
Important: Cables and connectors must be shielded for stable system performance. If an installation does not use
Shure EC 6001 cables, they must follow the Cat5e cable requirements.
Using Patch Panels
When designing a system with a patch panel, crimp the cable to the female shielded connector on the panel. Then simply
use short jumper cables to connect to the microphone units. Make sure the chain is always terminated by a microphone
unit or a termination plug included in the SPS CU spare parts package.
Installation Best Practices
Follow these guidelines for the most reliable installation.
Continuity of Shielding
Shielding must be consistent through the DCS-LAN chain. Any cable or patch panel used for DIS components requires
shielded RJ45 connectors. All DIS components feature shielded RJ45 female connectors.
Avoiding Accidental Grounding (Galvanic Isolation)
Avoid accidentally grounding the DCS-LAN signal with the chassis ground of a patch panel. The DCS-LAN uses the shield
as a signal ground reference and cannot contact another ground anywhere in the connection.
Plastic Frame
Space between connectors
Avoid Grounding in a Patch Panel
To avoid ground issues:
• Plastic frames in patch panel: this ensures that the female JR45 connectors do not ground to the chassis of the patch
panel.
• Blank space between connectors: leave a space between each female RJ45 connector in a patch panel.
• Shielding continuity: each component in the chain must be shielded properly.
Note: The female connectors in all DIS components units feature an air gap that isolates the chassis of the
connector and the chassis of the unit preventing any galvanic (physical and thus electrical) connection.

16
Properly Securing Cables
As with any cable carrying a signal, use care when installing the equipment.
Bending Rule
Do not sharply bend the cable. Ethernet cables cannot bend more than four-times the diameter of the cable.
Pinching
Do not over-fasten the cable. A pinched cable may not operate correctly.

17
Connection Diagrams
The following system diagrams illustrate typical hardware connections to the DIS-CCU central control unit. Actual
installations may use different combinations of hardware, but follow the general concepts outlined below.
Note: Flushmount and portable microphone units are interchangeable in the following drawings, unless noted.
Basic Setup with Microphone Units
The system is operational without the use of a computer. Use the CCU navigation screen to set up the installation.
A B C D
Basic System with Multiple Chains
Computer for Advanced Control
Connect a computer to the central control unit for comprehensive management of the system through a web browser.
Connect an Ethernet cable from the dedicated TCP/IP port to a computer.
TCP/IP
Computer Control
Connect the CCU TCP/IP port to computer

18
Tablet or Laptop for Wireless Control
Use a wireless router to access the web browser from a laptop or tablet. The web browser on a mobile device offers the
same comprehensive system management.
TCP/IP
CCU TCP/IP port to router
Wireless Control
Interpretation Units
The DCS 6000 system supports simultaneous interpretation for up to 31 languages, routing the interpretation channels to
each microphone unit. Typically, a separate room or booth is dedicated for interpreters for greater sound isolation.
A B C D
Booth 1 Booth 2 Booth 3
Interpreter Stations
Interpretation Units

19
Audio Recorder
Connect an audio recorder to the analog outputs of the CCU to record floor audio, translations, or a specific set of
microphones. Use the browser interface to buss units to groups and assign them to the specific output (A-H). Connect the
XLR outputs of the CCU to the inputs of an audio recorder.
Out A Out B Out C Out D Out E Out F Out G Out H
Analog outputs to recorder
Recording Audio
Mixer or DSP
Connect a mixer to the CCU analog outputs to control individual microphone volume or equalization. Use the browser
interface to buss units to groups and assign them to the specific output (A-H).
To return the audio to the DCS 6000 system:
1. Connect the output of the external device to Audio Input 1 on the CCU
2. Route the Input 1 audio by selecting the Loudspeaker and Ch. 0 and deselecting Out A (Group) Audio > Input Control >
Audio In 1
3. To avoid a feedback loop, turn off the internal Floor routing by deselecting Loudspeaker and Ch. 0: Audio > Input Control
> Floor
Out A Out B Out C Out D Out E Out F Out G Out H
Analog outputs to DSP
DSP back to CCU Audio Input
Inserting a Mixer or DSP

20
Wireless Language Distribution
For additional monitoring, connect a wireless language distribution system to one of the CCU audio outputs. Use the
browser interface to select the desired microphones (seat) for that group output (A-H). The DCS 6000 Digital Infrared
Language System transmits this audio signal to a number of listening stations.
Out A Out B Out C Out D Out E Out F Out G Out H
Booth 1
Booth 2
Booth 3
Analog outputs to digital transmitter
IR radiator
Receivers
Wireless Language Distribution
Emergency Signal
Input 2 is designed to broadcast an Emergency Evacuation Message (EEM), overriding the meeting in the event of an
emergency. A switch (normally-open) must be connected to the emergency switch connector. When the switch is closed
an "Emergency Evacuation Message (EEM)" audio signal present on the 'In 2' input is distributed to all output channels,
overriding all other audio inputs.