Cambridge Sound Management Qt Emitters Operating instructions

Qt® Conference Room Edition
A speech protection system designed for conference rooms
Installation and Operations Guide

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Qt Conference Room Edition Installation and Operations Guide
Contents
Safety
Packing list
Introduction
General
Using sound masking to protect privacy of conference rooms
Full feature list
Planning the system
Sound masking guidelines
Choosing where to install emitters – what is an exposed wall?
Emitter spacing and ceiling height
Emitter layout – normal installation – two rows of emitters
Emitter layout – when to use up to 4 rows of emitters
Controller and privacy sign layout
Installation
Pre-wiring
Installing qt emitters
Custom cabling guidelines
Installing the controller and privacy signs
System set-up and calibration
Acoustic calibration
System conguration via the front pane
User mode
Set-up mode
System acoustic calibration
Special installation cases
Troubleshooting
Warranty
Zone destination records
Hole cut guide for ush mount box
Hole cut guide for privacy sign
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CONTENTS

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Qt Conference Room Edition Installation and Operations Guide
SAFETY
Safety
Important Safety Instructions:
1. Read these instructions.
2. Keep these instructions.
3. Heed all warnings.
4. Follow all instructions.
5. Do not use this apparatus near water. Indoor use only.
6. Clean only with dry cloth.
7. Do not block any ventilation openings. Install in accordance with the manufacturer’s instructions.
8. Do not install near any heat sources such as radiators, heat registers, stoves, or other apparatus
(including ampliers) that produce heat.
9. Do not defeat the safety purpose of the polarized or grounding-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 wide blade or the third prong is provided for your safety. If the provided plug does not t
into your outlet, consult an electrician for replacement of the obsolete outlet.
10. Protect the power cord from being walked on or pinched particularly at plugs, convenience
receptacles, and the point where they exit from the apparatus.
11. Only use attachments/accessories specied by the manufacturer.
12. Unplug this apparatus during lightning storms or when unused for long periods of time.
13. Refer all servicing to qualied 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.

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Qt Conference Room Edition Installation and Operations Guide
Packing List
The package includes:
▪1 Wall-mounted ST 1000 control module
▪1 4-gang adaptor plate for control module (used for 3-gang EU/UK boxes)
▪2 Automatically lighted privacy signs
▪2 1-gang adaptor plate for privacy signs
▪1 Power supply
▪8 Qt Emitters
▪7 16 ft audio cables
▪1 50 ft homerun audio cable
▪2 50 ft two-conductor cables for privacy signs
▪1 Hole saw
▪4 Privacy sign 6/32” x 3/8” screws
▪8 Wall plate adapter 6/32” x 3/8” screws
▪4 Control module back panel 6/32” x 5/8” screws
PACKING LIST

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Qt Conference Room Edition Installation and Operations Guide
Introduction
General
Using Sound Masking to Protect Privacy of Conference Rooms
The Qt Conference Room Edition (QtCRE) from Cambridge Sound Management is a very cost-
effective solution to provide condential speech privacy for conference rooms, executive ofces and
suites, boardrooms and other sensitive spaces, to the immediate areas surrounding such spaces. For
convenience we may refer to all such rooms as conference rooms although that may not be their actual
use. The system comprises sound masking emitters and a lighted privacy sign placed immediately
outside such sensitive room indicating when the system is operational, and a QtCRE controller and
identical privacy sign inside the room. The system does not place sound masking emitters inside the
sensitive space itself.
The acoustical attenuation performance of walls and other construction surrounding conference
rooms can vary widely. Even if high quality materials with high STC (sound transmission class) ratings
are installed with the intent of providing adequate sound attenuation, the expected result may not
be achieved if the surrounding space is sufciently quiet. There may be sound leaks under doors
or an HVAC serves as a “sound tubes” to adjacent spaces. Acoustical ceilings may be intended to
provide good sound absorption but these same lightweight tiles usually allow substantial speech
sound to transmit through them to plenums above and back down to ofces adjacent the conference
room. Return air grills into plenums common to both the conference room and exterior spaces are a
frequent privacy issue. Background noise from a high quality building HVAC system may be so low
that it provides no signicant masking of speech sound escaping the conference room. The common
use of modern energy-efcient variable air volume HVAC systems can further exacerbate this problem.
Remedial work to the construction or HVAC system to improve privacy can be very costly, and even
then may not achieve satisfactory results. On the other hand a dedicated electronic sound masking
system around the conference room is cost effective and will provide condential privacy in almost all
applications.
A conference room speech privacy protection system differs from typical ofce-wide sound masking
system in three important ways.
1. The sound masking is applied only to a select small area – the exposed area around the perimeter of
the conference room.
2. Rather than operating 24/7 the QtCRE sound masking optionally may be turned on and off by users.
3. The resulting speech privacy protection status is indicated in the conference room and the entrance
to it by lighted signs.
The QtCRE sound masking levels can be calibrated using Cambridge Sound Management’s Qt100
Conguration iPad app, iMic microphone, and Bluetooth dongle (used to connect the iPad to the
QtCRE unit) or by a calibrated sound level meter with octave band lter set or analyzer. If using iPad
app, set levels directly below rst row of emitters
INTRODUCTION

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Qt Conference Room Edition Installation and Operations Guide
Full Feature List
▪Comes standard with two automatically lighted privacy signs and cables, wall-mounted control
module (controller) and power supply, mounting brackets, 8 emitters, seven 16 ft. (4.8m) audio
cables, 50 ft. (15.2m) homerun audio cable, and hole saw
▪Sound masking level adjustable in ½ dB steps
▪Out of the box support for conference rooms with up to 40 ft. (12m) of exposed walls
▪Optional add-on emitters for larger areas
▪Simplied software for easy customer operation
▪More advanced functions accessible by installer
▪Premium, minimalist design style to t in with other conference room AV equipment
▪Smooth ramp up and down sound masking level function to inhibit disruption outside the
conference room
▪Controllable from in-room Crestron and AMX control systems via contact closure; also offers 5V
trigger output
▪Straightforward, low-impact installation
▪Can be left on 24/7 or turned on as needed during condential meetings
▪Less than 7 watts power consumption
▪Power supply compatible with 100V to 240V AC power mains.
INTRODUCTION
Alternatively, levels may be set using the standard settings chart later in the manual, which will work ne
for most installations.
The QtCRE control module supports one zone of sound masking with 2 cable homeruns. Each run
supports up to 60 emitters. The maximum coverage area for the QtCRE is 12,000 sq. ft. (1,115 m2)
although typical conference room speech privacy installations will not require coverage for such a large
area.

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Qt Conference Room Edition Installation and Operations Guide
PLANNING THE SYSTEM
Planning the System
Sound Masking Guidelines
Choosing where to install emitters – what is an exposed wall?
This manual covers system installation of the controller, privacy signs and emitters, as well as masking
level setting and system maintenance. This introduction section discusses guidelines to ensure effective
sound masking coverage.
Generally the layout and calibration of emitters outside a conference room follow the standards for
an open ofce design. It is important that the masking volume be set correctly to achieve the full
effectiveness of the system. If volume levels are set too low, speech privacy for the conference room
occupants will be reduced and people outside the conference room may nd audio leakage to be
more distracting. If volume levels are set too high, the masking sound itself could become a source of
distraction.
In a given open ofce design, including ceiling height, ceiling material and workstation panel height,
we can dene the masking volume required to achieve “normal acoustic privacy,” between ofces
(i.e., normal voices are audible but not easily understood). In an open ofce environment, the target
background sound level is typically in the 45–48 dBA range, as measured 3 - 4 ft. (0.9 m) above oor
level.ft
The goal of the system is to lower the listener’s speech-to-masking noise ratio to the point that people
outside cannot understand any speech originating in the conference room, even from persons using a
raised voice. Technically this is known as Condential Privacy or having an Articulation Index (AI) of 0.05
or below and is comparable to a Speech Transmission Index (STI) of 0.12 or below.
In order to achieve this goal, the emitters should be installed in rows parallel to all exposed walls of the
conference room, that is, along any wall party (common) to both the conference room and any adjacent
ofce spaces, including open plan or private enclosed ofces, corridors, storage or utility rooms, etc.
Ceiling Height
8’ (2.4 meters)
10’ (3 meters)
12’ (3.6 meters)
13 - 16
15 - 18
16 - 19
45 - 48 dBA
45 - 48 dBA
45 - 48 dBA
Volume Level Intended Result (at listener ear level)

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Qt Conference Room Edition Installation and Operations Guide
PLANNING THE SYSTEM
Emitter spacing and ceiling height
Spacing between emitters generally should follow the same rules as for other CSM direct eld masking
systems, i.e. should be not less than the ceiling height above the nished oor. The English dimensions
are based on America drop ceiling tile sizes (24x24”, 24x48”). The metric dimensions are based on
international tile sizes (300x300mm).
Ceiling Height
Ceiling heights less than 10 ft. (2.4m)
Ceiling height is 10 up to 12 ft. (3m)
Ceiling heights 12 ft. and above (3.6m)
8 ft. spacing (2.4m)
10 ft. spacing (3m)
12 ft. spacing (3.6m)
Spacing

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Qt Conference Room Edition Installation and Operations Guide
PLANNING THE SYSTEM
Emitter layout – Normal installation – two rows of emitters
Place the rst row adjacent any party wall between the conference room and exterior spaces at ½ the
height of the ceiling or less, e.g. for a 10 ft. (3m) ceiling place the rst row no more than 4 or 5 ft. (1.2 to
1.5m) (from the wall. Continue both rows one spacing beyond both ends of party walls. However, for
party walls that are adjacent a narrow corridor or room one row on or near the center is sufcient.
Example: Conference room with one exposed wall – two rows of emitters.
Example: Conference room with two exposed walls and an open area extending away from the area in one direction. One row of emitters
in side cubicle area.

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Qt Conference Room Edition Installation and Operations Guide
PLANNING THE SYSTEM
Example: Installation with 3 rows of emitters
Emitter layout – When to use up to 4 rows of emitters
Consider using 4 rather than 2 rows of emitters in the conditions described below. Four rows may
not be required if no speech is intelligible beyond the rst two rows. To test for this have a colleague
go into the conference room, close all doors, and read some material with raised voice as though
addressing a conference. Listen in the area beyond the rst two rows of emitters while the masking
system is operating at its set level. The test should be done after all room nishes and furniture are in
place and when there are no atypical noise sources operating near the masking coverage area. The
test should be done when the ofce is unoccupied so that activity noise is absent. If the speech is not
intelligible under these conditions two rows are sufcient.
1. Conference rooms with speech reinforcement or other amplied sound such as computer playback
of speech
2. No plenum barrier above the conference room party wall
3. Open ceiling shared by conference room and protected areas
4. Glass or demountable partition party walls
5. Unusually quiet exterior spaces (less than 38 dBA ambient)
6. Highly sound reective (reverberant) spaces

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Qt Conference Room Edition Installation and Operations Guide
PLANNING THE SYSTEM
Controller and privacy sign layout
Options on how to control the system
It is important to understand how the system will be used and controlled to decide the location of the
controller and privacy signs.
The controller unit is self-contained and can be operated by the end-user directly from the front panel.
The set-up features are hidden from the end user to prevent accidental changes.
The signs indicate that the system is fully on only when lit steadily. They blink during ramping on and off
(the gentle increase or decrease of sound level).
Optionally the system can also be controlled via contact closure (such as by an automation control
system). In this case the controller should be placed out of the way, such as in a closet or IT closet, to
reduce any confusion about the active control point. The system also features a nominal 5V trigger out
for status conrmation to a control system.
An external contact closure can also be used to allow control from a remote switch such as a light switch
or single-pole, single-throw (SPST) low voltage switch.
In an operating scenario in which contact closure is used, emergency cutoff can only be achieved if the
low level is MUTE and CC ramp down time is 0.
Optionally the system may be installed similar to standard sound masking (which is normally on 24/7),
with the controller visible or hidden.
Placing the controller:
▪In a place easy to reach for occupants of the room, such as near light switches near the room
entrance, or at a convenient place accessible during presentations.
▪Can be visible or hidden, but remember people may not know how or where to operate it if its
completely out of sight.
Placing the privacy signs:
▪Two privacy signs are provided, one for the room occupants and the other for people outside the
room. Typically one sign is mounted inside the conference room to alert the occupants to status
and the other is mounted outside conference room, adjacent to the main door.
▪Use of both signs is not required or both may be installed inside or outside the room. Coordinate
with Owner.

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Qt Conference Room Edition Installation and Operations Guide
INSTALLATION
Installation
Pre-wiring
Homerun
The 50’ CAT distribution line supplied with the base kit should be sufcient as the
homerun for almost all installations. It may be replaced by a longer CAT cable
to the rst emitter without excessive loss or impact privacy signal level difference
between the rst and last emitters on the line. Theoretically a CAT coupler and
additional cable could be used rather than a longer homerun but this is not the
preferred method due to the coupler most likely being located in an inaccessible
and/or undocumented location, possibly complicating future servicing.
Emitter cable (interconnects) conguration
The interconnects should be connected the same as in a conventional CSM Qt
masking system, i.e. in a series serpentine layout. This will assure that adjacent
emitters are on different channels to minimize any phase interference issues.
CSM’s Quiet Technology uses four distinct non-correlated sounds that repeat every fourth emitter
automatically. The homerun from the controller to the rst emitter may be concealed in a wall stud
space.
How CSM emitter cabling works – homeruns and daisy chaining
Emitters on each line are daisy-chained in series during installation. Each emitter has passive internal
logic which rolls over its input channel to a different channel at its output port. Thus every fourth emitter
is actually operated in parallel with the rst.
Four Channel Distribution

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INSTALLATION
Power supply
In most cases the 24v power supply will need to be located remotely, with a cable run from the power
supply to the controller. In some cases a wall plate such as the Vanco 120614X permits in-wall running of
the power wire to an AC plug on the exterior of the wall.
The power supply wire may be extended using appropriate cable and connectors. The cable should be
UL rated and plenum rated if routed through any plenum space.
Audio Input
Optionally the QtCRE includes an audio input usable for music or paging. The input is fully functional
regardless of front panel or contact closure control. Therefore, the system may be used for music or
paging even when masking is muted or off.
Balanced Audio Input: (Most often, but not always characteristic of paging
systems.) Connect signal wires to + and - at the input. Connect the shield to
GND at the audio source.
Unbalanced Audio Input: (Typical of music systems.)
▪Mono Signals: Connect the mono signal wire to both L and R (split
the wire) on the block. Connect the ground wire to GND.
▪Stereo Signals: Connect the respective signal wires to L and R on the
block. Connect the ground wire to GND.
Contact closure input
This terminal can be used either for remote triggering by a Crestron, AMX, or other control system.
In either case, the contract closure takes priority over the front panel control settings. Contact closure
ramp speed can be set separately from front panel control ramp speed.
Trigger output
The trigger output provides nominally 5VDC when the system is operating at Normal level, for use
in triggering other devices or to provide an acknowledgment signal back to an external automation
system like a Crestron. Note that upon initiation of a downward ramp event, deactivation of the trigger
signal will lag the completion of the downward ramp by several seconds in addition to the ramp down
time parameter congured on the ST1000 control module. During a ramp-up to Normal operating level
event, the full and consistent activation of the trigger voltage may not be complete until the Normal
operating level is reached. Control system programs should be written to anticipate and accommodate
this behavior.

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Qt Conference Room Edition Installation and Operations Guide
USB connection
(special purpose
see page 14)
Sign is
active
USB connection
in use
INSTALLATION
Note that the small switch on the side of the controller must be set to the “up” position (closer to the
top of the case) for the lights to work. The “down” setting enables the external USB jack, used for
rmware updates or for the optional Bluetooth dongle supplied with the Qt100 iPad app.
Connection to privacy signs
Run a separate cable from the controller mounting location to each lighting location. Do not daisy chain
signs as this may cause the lights to be of different brightness. Two 50 ft. (15.2m) plenum rated cables are
provided with the kit.
Sign 1 +
GND -
Sign 2 +
GND -
Control +
GND -
Note: Wiring nomenclature is
located under the removable
terminal block connector.

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Qt Conference Room Edition Installation and Operations Guide
INSTALLATION
Installing Qt Emitters
Important Considerations:
▪Each run has a maximum of 60 emitters!
▪Each run supports a maximum cable length of 1000 ft.
▪Each home run cable attached to the control module should be labeled by Zone # and Run #.
Adding a logical name (e.g. Marketing, Private Ofces) is suggested. In addition, ll out “Zone
Destination Record” at the end of this Guide.
▪The module has two identical outputs, Run 1 and Run 2. All emitters on Run 1 and Run 2 are
controlled equally.
▪Each job-made cable should be manufactured according to ANSI/TIA/EIA Standard 568-B. See
custom cabling guidelines on page 16.
▪Before installation, job-made cables should be tested with a LAN cable tester.
Installation:
1. Set the masking output level to the maximum level of 30.
2. Refer to the emitter layout and wiring diagram provided by the dealer for cable run connections.
3. Run home run cables from control module to the location of the rst emitter for all runs.
4. Gather all ceiling tiles (per layout drawing) that are to receive emitters. Use the supplied hole saw
to cut holes in designated tiles. Cut all tiles from the front. (Different types of emitter housings are
available to attach in areas where there are no suspended ceiling tiles.)
5. Push the emitter through the front of the hole in tile and secure it by pushing down and twisting the
locking ring at the back of the emitter.
6. Connect a run cable from the specied OUTPUT jack on the module to the INPUT jack of the rst
emitter. Listen to each emitter as it is connected. If you cannot hear its “whooshing” sound:
a. Try a different emitter.
b. Test all four previous cables for continuity and shorts. Repair any faulty cables.
c. If a short is detected, the masking will shut off until the short is physically xed. The error on the
control module will remain until the error is cleared. (see Clearing Error Codes, page 31) Set the
masking output level to the maximum level of 30.
7. Connect the next OUTPUT cable to the emitter OUTPUT jack.
Note:
▪The “tombstone” hook on the back of each emitter is next to the INPUT jack.
This can help you nd the INPUT jack by touch.
▪To adjust for unexpected obstacles such as sprinkler heads, each emitter may
be moved up to 2 ft. (one tile or 0.6 m) in any direction, if necessary.

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Qt Conference Room Edition Installation and Operations Guide
INSTALLATION
8. Run the cable to next designated tile specied on emitter layout and wiring diagram. Tie cables up
to structure or suspend from deck as required by local building code.
9. On the next emitter, connect this cable to the INPUT jack.
10. Repeat Steps 4 through 9 for the remaining emitters on the home run.
Set sound masking volume levels using either the front panel controls.
DO NOT put the input cable into the output port of the emitter. If sound is only heard by putting the
cable in the output, there is a problem earlier in the cable run. Be sure to x any problems and hear the
“whooshing” sound before installing the next emitter.
The input jack of each emitter bears this symbol
and is located near the safety tie off
The output jack of each emitter bears this symbol
Note:

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Qt Conference Room Edition Installation and Operations Guide
INSTALLATION
Custom Cabling Guidelines
Installing the controller and privacy signs
Important Considerations:
1. Use solid conductor 24 AWG CAT cable that meets local code requirements.
2. If the system is installed in a return air plenum, the cable must be plenum rated.
3. Shielding is not required. Unshielded twisted pair (UTP) cable is acceptable.
4. Snagless boots are not required.
5. RJ-45 plugs must use the “bent 3-tine” RJ 45 plugs intended for use with solid core CAT wire. Three
tine plugs can be purchased at a hardware store and from most CAT cable suppliers. DO NOT USE
the “aligned two-tine” type intended for stranded wire, as they provide improper contact and may
yield intermittent system operation. The diagram below shows the cross section view of both types.
6. Field test each cable after fabrication with the RJ-45 connectors (before nal installation), using
a standard network LAN cable tester, to check for continuity, shorts, and 1:1 (straight through)
connection.
Installation of the controller requires separating the front panel from the rear of the case – simply done
by pulling one from the other. All installation options require attaching the case rear rst, then getting
cables attached to the controller, then snapping the controller into place.
Controller Mounting Options
▪Best practices: If installing the controller on a wall known to have sound transmission issues into an
adjacent space, it is recommended to use surface mounting. Be careful to seal airtight any cabling
holes to minimize sound transmission. Avoid back-to-back mounting of electrical or other wall
components within a single stud space.
▪Best practices: On walls separating the conference room from an area with masking, don’t use
gang boxes with big holes as these are prone to passing sound. Whenever feasible, don’t install
the box on a wall requiring masking protection as it may exacerbate sound transmission problems
The controller may be mounted in several ways:
CORRECT
RJ-45 connector
with bent type
INCORRECT
RJ-45 connector
with aligned type

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Qt Conference Room Edition Installation and Operations Guide
INSTALLATION
Flush mount with supplied box
Cut hole in wall to dimensions x by x (use template) and run cables to this hole. After the cables have
been run to the hole in the wall, place the ush mount box in the wall (make sure up is actually up) and
snap the four clips that clamp to the back side of the drywall surface. Then attach the case rear to the
wall adapter. During installation if may be convenient to attach the wires to the tie-off point in the back
of the box to prevent the wires from falling back into the wall.
Controller
Case back panel
Flush mount box
3 3/4” x 7 1/2” (95 x 190mm)
hole in wall
(See template on page 35)
4x control module
back panel screws

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Qt Conference Room Edition Installation and Operations Guide
Surface mount on a suitable 4-gang electrical box (3-gang using EU/UK hardware)
4-gang electrical box (pre-installed or retrotted) – after the cables have been run to the box, use four
supplied screws to attach the wall plate adapter. (In the case of EU 3-gang boxes, use M3 or M3.5 screws
as needed – these are not included.) Then attach the system back to the wall adapter.
Note: The wall plate adaptor is ABS plastic and may be painted to match wall color. Use a standard
spray primer (Krylon) before painting.
INSTALLATION
Wall plate adapter
4-gang NEMA wall box
or low voltage clip
(not included)
Wall hole
8x wall plate
adapter screws
Controller
Case back
panel
4x control module
back panel screws
Wall hole
Wall plate adapter
3-gang EU/UK wall box
(not included)
6 x screw
(not included)
Controller
Case back panel
4 x #6
self-threading
screw

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Qt Conference Room Edition Installation and Operations Guide
INSTALLATION
Surface mount directly to the wall
Surface or panel mount of back plate – either with cables through hole (if cables can be run through the
wall) or out the side to end up on the surface of the wall or mounting point. Mark holes with template,
open up larger holes for cables if desired, run cables, attach back plate.
The wires may be run out the back of the case rear, or to the sides using the available openings.
Consult a knowledgeable person about the best type of hardware to attach to your wall surface.
Installing the controller to the back plate.
After all cables have been attached, snap the controller in place.
After installation, the controller can be removed by pulling it, and it will snap away from its back,
exposing the cabling and also giving access to the mounting points.
Controller
Wall screws (not included)
Approximate hole locations
(use case back as template)