Dolby Laboratories 126 User manual

Dolby System 126
Owner's Manual
1 April 2023
Issue 1 Part number: 8800329

Notices
Copyright
© 2023 Dolby Laboratories, Inc. All rights reserved.
Dolby Laboratories, Inc.
1275 Market Street
San Francisco, CA 94103-1410 USA
Telephone [phone]
Fax [phone]
http://www.dolby.com
Trademarks
Dolby and the double-D symbol are registered trademarks of Dolby Laboratories.
The following are trademarks of Dolby Laboratories:
Dialogue Intelligence™
Dolby®
Dolby Advanced Audio™
Dolby Atmos®
Dolby Audio™
Dolby Cinema®
Dolby Digital Plus™
Dolby Digital Plus Advanced Audio™
Dolby Digital Plus Home Theater™
Dolby Home Theater®
Dolby Theatre®
Dolby Vision®
Dolby Vision IQ™
Dolby Voice®
Feel Every Dimension™
Feel Every Dimension in Dolby™
Feel Every Dimension in Dolby Atmos™
MLP Lossless™
Pro Logic®
Surround EX™
All other trademarks remain the property of their respective owners.
Patents
THIS PRODUCT MAY BE PROTECTED BY PATENTS AND PENDING PATENT APPLICATIONS IN THE UNITED
STATES AND ELSEWHERE. FOR MORE INFORMATION, INCLUDING A SPECIFIC LIST OF PATENTS PROTECTING
THIS PRODUCT, PLEASE VISIT http://www.dolby.com/patents.
Product model
THIS DOCUMENTATION APPLIES TO PRODUCT MODELS: CID1026 and CID1027.
Limited warranty and warranty exclusions
THE LIMITED WARRANTY AND WARRANTY EXCLUSIONS MAY BE FOUND AT THE FOLLOWING URL: https://
www.dolby.com/us/en/about/warranty-and-maintenance-policies.html
Notices
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Contents
1 Important safety and regulatory information............................................................................................4
2 Introduction to Dolby System 126.............................................................................................................. 7
2.1 About this documentation....................................................................................................................8
2.2 CS126MH key features and benefits..................................................................................................... 8
2.3 CS128LF key features and benefits.......................................................................................................9
2.4 System 126 preinstallation information .............................................................................................. 10
2.4.1 System 126 screen placement and acoustic center information ................................................. 10
2.4.2 System 126 configuration modes................................................................................................... 12
2.5 Selecting the wire for System 126.........................................................................................................13
2.6 GLL format files for soware simulation modeling............................................................................. 14
2.7 Additional information..........................................................................................................................14
2.8 Contacting Dolby .................................................................................................................................. 15
3 Assembling and installing System 126....................................................................................................... 16
3.1 Assembling and Securing the CS128LF................................................................................................ 17
3.2 Installing the optional full-range crossover into the CS126MH...........................................................18
3.3 Installing the CS126MH onto the CS128LF........................................................................................... 22
3.4 Aiming Dolby System 126......................................................................................................................24
3.5 Connecting and configuring Dolby System 126MH..............................................................................28
3.5.1 Connecting the CS126MH................................................................................................................28
3.5.2 Connecting and configuring the CS128LF...................................................................................... 30
3.5.3 Configuring System 126 in bi-amplifier mode............................................................................... 32
3.5.4 Configuring System 126 in single-amplifier channel mode.......................................................... 35
4 Dolby System 126 and system components specifications.......................................................................37
4.1 Dolby System 126 specifications for bi-amplifier mode......................................................................38
4.2 Dolby System 126 specifications for single-amplifier mode .............................................................. 39
4.3 Dolby CS126MH specifications..............................................................................................................40
4.4 Dolby CS128LF specifications............................................................................................................... 41
4.5 Dolby System 126 dimensions.............................................................................................................. 42
5 Dolby System 126 digital signal processing requirements........................................................................43
5.1 CS126MH and CS128LF single-amplifier channel digital signal processing requirements................44
5.2 Dolby CS126MH bi-amplifier digital signal processing requirements.................................................45
5.3 Dolby CS128LF bi-amplifier digital signal processing requirements.................................................. 46
6 System limiters............................................................................................................................................ 47
6.1 Setting system limiters..........................................................................................................................48
7 Documentation revision history................................................................................................................. 50
Contents
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1
Important safety and regulatory information
Safety
INSTALLER ASSUMES ALL RESPONSIBILITY AND LIABILITY FOR THE INSTALLATION OF
THIS PRODUCT.
No information contained in this guide is intended as a warranty on the part of Dolby.
Anyone using this information assumes all liability arising from its use. Product
abuse, use of the product not in accordance with Dolby instructions, or use in an
application for which the product has not been designed is not covered under any
Dolby warranty, nor is Dolby liable for any loss or damage.
Installation must be performed by qualified, licensed, and insured installers, and in
accordance with all laws, rules, and regulations applicable to the installation site.
Failure to do so could result in serious personal injury or even death. Prior to
installing this product, read and completely understand the installation instructions.
You must read these instructions to prevent personal injury and property damage.
Keep the installation instructions in an easily accessible location for future reference.
A licensed professional engineer must approve the placement and method of
attachment to the building structure prior to the installation of the system.
All information presented herein is based upon materials and practices common to
North America and may not directly apply to other countries because of diering
material dimensions, specifications, and/or local regulations. Installers in other
countries should consult with appropriate engineering and regulatory authorities for
specific guidelines.
Any supplied rigging hardware is intended only for use with the specified speaker(s).
The installer assumes all risk of loss and/or injury arising out of the use of the
supplied rigging hardware with any other speaker. All other rigging is considered part
of the venue and/or installer-supplied equipment and is not addressed in this guide.
This guide is not a comprehensive source for rigging in general. Installer assumes all
responsibility for ensuring that accepted rigging and safety practices are employed.
Installer assumes all responsibility for the appropriate use of Dolby supplied rigging
hardware and follows at a minimum all applicable laws, rules, and regulations in
force for each venue.
No open flame sources should be placed on or near the apparatus. Do not install near
any heat sources such as radiators, heat registers, stoves, or other apparatus that
produce heat.
Storage temperature: -4 to +140°F (-20 to +60°C). The products covered by this
manual are not intended for use in high-moisture environments. Moisture can
damage the product and cause corrosion of electrical contacts and metal parts. Avoid
exposing the speakers to direct moisture. Keep speakers out of extended or intense
direct sunlight. Premature product failure or serious personal injury could occur if
this product is used outdoors or in wet indoor environments.
Important safety and regulatory information
Dolby System 126 Owner's Manual 4
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Dolby is not responsible for the application of its products for any purpose or the
misuse of this information for any purpose. Furthermore, Dolby is not responsible for
the abuse of its products caused by avoiding compliance with inspection and
maintenance procedures or any other abuse.
This product is intended for indoor use only.
Do not block any ventilation openings. Install in accordance with the instructions as
detailed in this manual and the Product Information document.
When a rolling cart is used to transport the speaker, use caution when moving the
cart/speaker system to avoid injury.
Refer all servicing to qualified service personnel. Servicing is required when the
apparatus has been damaged in any way.
This product may require installation in a restricted access location. Please refer to
this manual and to the Product Information document.
Caution: Hearing damage can occur by prolonged exposure to
excessive sound pressure level (SPL); the speaker is easily
capable of generating SPL suicient to cause permanent
hearing damage to performers, production crew, or audience
members. Caution should be taken to avoid prolonged
exposure to SPL in excess of 90 dB.
Caution: Vibration from this type of speaker system may
cause cabinets to shi. Failure to secure the speaker cabinet
to the building structure may result in the speaker system
tipping or falling, which may cause damage or injury.
Caution: Make sure that no water pipes, natural gas lines,
electrical wire, or conduit are present where the speaker is to
be installed. Cutting or drilling into water pipes, natural gas
lines, electrical wire, or conduit could cause serious personal
injury or property damage.
Caution: Use proper liing techniques when working with
heavy objects to avoid personal injury. Always be careful
when moving the CS128LF or the assembled Dolby System
126 and employ at least two people when attempting any
relocation of the speakers, as there is danger of tipping if
the system is not secured to the building structure.
High temperature warning: The speaker system may reach
elevated temperatures during operation. Always remove all
drive signals and allow ample time for the system to cool
down prior to handling.
To reduce electric shock, do not expose the apparatus to dripping or splashing; no
objects filled with liquids, such as mugs, shall be placed on the apparatus.
Caution: Troubleshooting must be performed by a trained
electrician. To reduce the risk of electric shock, do not attempt
to service this equipment unless you are qualified to do so.
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SAFETY SYMBOL KEY
Caution: This symbol that appears on the unit and/or instruction manual is intended to
alert the user to the presence of important safety operating and maintenance
instructions.
Warning:
This symbol that appears on the unit and/or instruction manual is intended to alert the user to the
presence of uninsulated "dangerous" voltage within the product enclosure that may be of suicient
magnitude to constitute a risk of electric shock to persons.
High temperature warning:
This symbol that appears on the unit and/or the instruction manual is intended to alert the user that
the item can be hot and that care must be taken accordingly.
EU environmental regulations/compliance and product disposal information
Restriction of Hazardous Substances Directive (RoHS): All Dolby products comply with the
requirements of the EU RoHS Directive. This product is electronic equipment and should be disposed
of in accordance with all applicable laws.
Do not dispose as household waste. Do not dispose of the product in a fire. Please dispose of this
product by taking it to your local electronic waste collection point or recycling center. For information
regarding where to recycle electronic equipment, contact your local dealer. For additional information
regarding Waste Electrical and Electronic Equipment (WEEE) and product disposal go to http://
www.dolby.com/us/en/about/environmental-commitment.html.
CID1027 EAC RoHS information
Product model CID1027 complies with EAC RoHS requirements.
Important safety and regulatory information
Dolby System 126 Owner's Manual 6
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2
Introduction to Dolby System 126
The Dolby System 126 is designed to meet the needs of a high-performance screen speaker in small to
medium Dolby Atmos or 7.1 Cinemas, especially those rooms with minimal space behind the screen.
The Dolby System 126 delivers consistent audio coverage and uniform volume shading for every seat in
the venue up to approximately 49.9 feet (15.2 meters) in depth. The Dolby System 126 consists of a
CS126MH speaker for mid and high frequencies and a CS128LF speaker for low frequencies, providing
greater intelligibility and enhanced low-frequency extension. These components are coupled together
to create a screen speaker system that provides better audience coverage, lower distortion
(discomfort), and increased low-frequency response. With intuitive ergonomic design and features, the
Dolby System 126 enables quick, easy installation and service. Built on the foundation of the Dolby
industry-leading system design and support philosophy, the Dolby System 126 provides elevated
performance and streamlines speaker integration.
Figure 1: Dolby System 126 full speaker stack
Following is an outline of this chapter:
•About this documentation
•CS126MH key features and benefits
•CS128LF key features and benefits
•System 126 preinstallation information
•Selecting the wire for System 126
•GLL format files for soware simulation modeling
•Additional information
•Contacting Dolby
Introduction to Dolby System 126
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2.1 About this documentation
This documentation describes the key features and benefits of Dolby System 126 and shows you how to
install the system in a typical cinematic exhibition environment.
2.2 CS126MH key features and benefits
The Dolby System 126 utilizes one CS126MH unit, which consists of an asymmetrical high-frequency horn
with a high-performance transducer, and a low-distortion 10-inch midrange driver. This configuration
provides improved pattern and amplitude control within the high-frequency operating range, yielding
smoother response and coverage to all seats in the auditorium.
Figure 2: CS126MH rear (le) and front (right)
• The high-frequency driver is a very low-distortion 1.7 inch (43.2 mm) polyimide dome driver with a
frequency response up to 20 kHz.
• The mid-frequency driver is a high sensitivity 10-inch transducer with an optimized Finite Element
Modeling (FEM) motor and suspension with optimized cooling for low power compression.
• The advanced input plate features a high-current, spring-loaded terminal block that enables quick
installation without the need for spade lugs or a crimping tool.
• The CS126MH assembly mounts directly to the top of a CS128LF unit and features independent horizontal
and vertical aiming adjustments.
• The ports on the front and back of the unit provide natural convection cooling.
• The unique asymmetrical high-frequency horn design provides long-distance coverage to the back of the
auditorium from the top of the horn, while the bottom of the horn provides wider coverage and volume
shading for the audience closer to the screen. This provides greatly improved coverage for the auditorium
in comparison to conventional horn designs.
• An optional crossover is available for single channel, full-range operation. This crossover mounts in the
top of the CS126MH and wires down into the CS128LF, which allows a single amplifier to drive the entire
system.
Introduction to Dolby System 126
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Figure 3: Dolby asymmetrical horn coverage
2.3 CS128LF key features and benefits
Dolby System 126 utilizes a single CS128LF to produce low frequencies.
Figure 4: CS128LF rear (le) and front (right)
• Each unit contains two 15-inch woofers that can be driven in parallel or driven individually to maximize
available amplifier power.
• Each 15-inch driver is contained in an independent chamber within the cabinet to provide improved
performance and reliability.
• On the CS128LF, a unique flip-card allows you to change the electrical routing for parallel wiring of the
drivers powered from a single amplifier channel, or individual wiring to the amplifier channel on each
driver. With the CS128LF flip-card, you can easily select either bi-amplifier mode or single-amplifier mode
without the need of any additional tools.
CS128LF key features and benefits
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• The close spacing of the woofers to each other, combined with placing the pair toward the top of the
cabinet, improves system vertical dispersion.
• Rubber feet on the bottom of the cabinet help with stability and isolate the cabinet from transmitting
vibration to the building structure.
• Dual side acoustical ports (one on each side of the cabinet) can be used as integrated handles to improve
safety and comfort during handling and installation.
• A BKT.FLR floor bracket kit, which is available from Dolby (sold separately), enables secure installation of
the speaker system to the building structure. The kit includes two brackets and four M10 washers.
• CS128LF attachment points are provided for connecting to the auditorium building structure only; they
are not intended for hanging or flying the speaker. Always adhere to local building codes in your region.
• The advanced input plate features a high-current, spring-loaded terminal block that enables quick
installation with no spade lugs or crimping tool needed, vastly simplifying installation.
2.4 System 126 preinstallation information
Preinstallation information is provided for the System 126.
2.4.1 System 126 screen placement and acoustic center information
In a typical auditorium, the Dolby System 126 is installed behind the screen, with the acoustic center of the
speaker located two-thirds of the distance from the bottom of the screen.
The placement of the speakers behind the screen should follow the guidance provided in the Dolby Atmos
Specifications for cinema, or industry standard guidance for a 7.1 screen. To improve localization and
smooth pan-throughs, larger cinemas can benefit by adding le-center and right-center screen speakers. You
may need to build a screen platform to position the speaker system to the correct height. A screen platform
must be secured to the building structure.
Caution: Design and construction of a screen platform must be performed by a qualified, licensed,
and insured professional in accordance with all laws, rules, and regulations applicable to the
installation site. Failure to do so could result in serious personal injury or even death.
Figure 5: Typical auditorium installation
Introduction to Dolby System 126
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The elevation of the speaker system should be located with the acoustic center of the horn positioned
exactly two-thirds the distance from the bottom of the screen. The acoustic center of the speaker system is
1.54 meters (60.65 inches) above the building structure from which it is secured, as shown in the following
figure.
Figure 6: Dolby System 126 acoustic center
The Dolby System 126 is designed to be placed as close to the screen surface as possible, with a minimum
distance of 5-7 cm. This minimizes high-frequency reflections (screen loss) but does not locate the speaker
too close to the screen. When aiming the system, angling of the CS126MH may require that the speaker
system be set back from the screen to accommodate proper tilting and aiming.
Caution: Always be careful when moving the Dolby System 126 or the assembled Dolby System 126,
and employ at least two people when attempting any relocation of the speakers, as there is a danger
of tipping if the system is not secured to the building structure.
System 126 preinstallation information
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Figure 7: System 126 screen planes
2.4.2 System 126 configuration modes
You can install the Dolby System 126 in two configurations. These dierent configuration modes are based on
the number of amplification channels used.
• Single-amplifier mode is for auditoriums with a maximum depth of 40.7 feet (12.4 meters).
• Bi-amplifier mode is for auditoriums with a maximum depth of 49.9 feet (15.2 meters).
For single-amplifier mode, a single pair of wires is connected to the speaker stack from the amplifier. A full-
range crossover (PXO.126) is installed in the top of the CS126MH cabinet to route the audio correctly. A short
pair of installer-provided jumper wires connects the CS126MH to the CS128LF. For single-amplifier mode,
the PXO.126 is sold separately by Dolby and must be installed in each System 126.
Introduction to Dolby System 126
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Figure 8: System 126 single-amplifier mode
For bi-amplifier mode, two pairs of wires are connected to the speaker stack from two amplifier channels.
One pair connects to the CS126MH for mid/high-frequency audio, and the second pair connects to the
CS128LF for low-frequency audio. No optional crossover (PXO.126) is used for this configuration.
Figure 9: System 126 bi-amplifier mode
2.5 Selecting the wire for System 126
It is important that you select the correct wire gauge for System 126.
Typically, no more than 0.5 dB (or 11%) of power should be lost in the cabling. The System 126 input plates
accept an American Wire Gauge (AWG) of 18 AWG to 6 AWG (1 mm2 to 16 mm2). When selecting the wire
gauge, you should always follow industry-standard practices, based on the rated impedance of the speaker
and the cable length.
For Dolby System 126, we recommend a wire gauge of 16 AWG to 12 AWG (1.5 mm2 to 4 mm2).
Selecting the wire for System 126
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Note: The input terminals are marked with indicators to show the polarity. Per International
Electrotechnical Commission (IEC) standards, a positive voltage on the positive marked input results
in the transducers moving outward. You must verify the positive and negative markings for each
respective product. Always tie the cable down to the available hardware to minimize any buzzing or
pullouts. If possible, aer wiring is completed, play sound through the speaker to identify any
connection issues, buzzing, or rattling.
2.6 GLL format files for soware simulation modeling
There are .gll files that you can use to simulate Dolby System 126 in acoustical simulation soware.
You can download a folder (Dolby_Screen_System_126_GLL_Files.zip) that contains the .gll
files at https://professional.dolby.com/product/cinema-audio-products/System126/. To run the .gll files,
use EASE or EASE Focus soware. You can download EASE Focus soware at no charge from https://
focus.afmg.eu/index.php/fc-downloads-en.html.
Dolby System 126 .gll file descriptions
There are two .gll files for Dolby System 126, CS128LF.gll and CS126MH.gll.
CS128LF.gll
• The filename for the LF portion of the Dolby System 126 screen channel is Dolby_CS128LF.
• For correct simulation, place the LF entry point (z axis) at the height of the CS128LF speaker cabinet base
in the auditorium.
• The GLL preset defaults to the Dolby System 128, so select Sys126 in the input configuration for correct
bi-amplifier System 126 simulation.
• Select Sys126 passive in the input configuration if you are using the optional crossover for single-
amplifier channel operation.
• When simulating the bi-amplifier Dolby System 126 setup, we recommend experimenting by removing
the default 0.75 ms delay if the reference listening position is at or above the placement of the screen
channel. Since this delay is coded into the GLL, you can null it by adding a 0.75 ms delay to the CS126MH,
which equals the LF delay.
CS126MH.gll
• To finish the Dolby System 126 screen channel, use the Dolby_CS126MH file.
• Place the CS126MH height entry point (z axis) at 1.53 m (5 ) above the height entry point of the
CS128LF.GLL. The x and y axes should match the settings of the LF.
• The CS126MH.GLL file can then pan ±20 degrees horizontally, and tilt ±15 degrees, independent of the
CS128LF, as it would in a typical configuration.
• The GLL preset defaults to the System 126 bi-amplifier setup. Select Sys126 passive in the input
configuration if you are using the optional crossover for single-amplifier channel operation.
• When simulating the single-amplifier channel operation, we recommend experimenting by changing the
CS126MH polarity to negative if the reference listening position is at or above the placement of the screen
channel.
2.7 Additional information
There is additional information regarding System 126 that you need to consider.
• System weight for stability calculations is approximately 79.2 kg (174.7 lb).
• Allow at least 11 inches (30 cm) between the port exits and any obstruction (including side wall or bale
wall construction). Blockage of the ports results in reduced low-frequency extension and a decreased life
span of the product.
• Amplifier selection is aided by additional data, as indicated in the Dolby System 126 specifications. (See
the link at the end of this section.)
Introduction to Dolby System 126
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• The power-draw specification provides the actual power draw in watts at the rated Vrms in the design,
instead of calculated power. This can aid in optimizing amplifier power budgets, as the measured power
is almost always lower than the calculated power (sometimes significantly).
• The maximum voltage peak specification is useful for selecting an amplifier that has a voltage rail at or
above the rating for the speaker maximum dynamic performance. Some amplifier companies provide this
data in their respective technical data sheets (or provide the data by request).
Related information
Dolby System 126 and system components specifications on page 37
2.8 Contacting Dolby
You can contact Dolby Cinema Solutions and Support using email or regional telephone numbers. You can
also access documentation by visiting the Dolby customer portal.
Contact Dolby Cinema Solutions and Support
• Send an email to [e-mail].
• Call:
AMERICAS: [phone]
ASIA, CHINA, and PACIFIC RIM: [phone]
EMEA: [phone]
JAPAN: [phone]
Access documentation
Visit https://customer.dolby.com.
Submit feedback about this documentation
Send an email to [e-mail].
Contacting Dolby
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3
Assembling and installing System 126
Instructions are provided for assembling and installing System 126. Each section of instructions
specifies the tools that are needed to complete the required tasks. Refer to each section for more
details on required tools.
Note: BKT.FLR floor brackets are available from Dolby (sold separately) to secure the
speaker system to the building structure. When using the BKT.FLR brackets, the installer
must supply the mounting hardware necessary to secure the speaker system to the
building structure. The holes in the bracket are sized for M10 or 3/8-inch bolts.
Caution: Vibration from this type of speaker system is high and may cause cabinets to
shi. Failure to secure the bottom speaker cabinet to the building structure may result in
the system tipping or falling, which may cause damage or injury.
Caution: Dolby disclaims any liability, including damage or injury, for the use of
mounting hardware, supports, and brackets not supplied by Dolby. Any modification to
the speaker system (for example, mounting by drilling holes into the speaker system) will
render the product warranty null and void.
Following is an outline of this chapter:
•Assembling and Securing the CS128LF
•Installing the optional full-range crossover into the CS126MH
•Installing the CS126MH onto the CS128LF
•Aiming Dolby System 126
•Connecting and configuring Dolby System 126MH
Assembling and installing System 126
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3.1 Assembling and Securing the CS128LF
Instructions are provided for assembling and securing a CS128LF.
About this task
The following tools are needed to secure the Dolby CS128LF:
• 6 mm hex driver or wrench
• BKT.FLR brackets
• Installer-provided serviceable thread-locking compound (recommended)
• Installer-provided acoustic or non-hardening caulk (recommended)
Procedure
Caution: Vibration from this type of speaker system is high and may cause the cabinets to shi.
Failure to secure the bottom speaker cabinet to the building structure may result in the speaker
system tipping or falling, which may cause damage or injury.
Caution: Dolby disclaims any liability, including damage or injury, for the use of mounting hardware,
supports, and brackets not supplied by Dolby. Any modification to the speaker system (for example,
mounting by drilling holes into the speaker system) will render the product warranty null and void.
Attention: The Dolby System 126 was designed to be placed as close to the screen as possible, within
5-7 cm. When aiming the system, angling of the CS126MH may require that the speaker system be set
back from the screen to accommodate proper tilting and aiming.
1. Determine the proper placement of the system.
Note: Check with local building codes, and always refer the installation to a qualified professional.
2. Remove the four M10 bolts from the bottom sides of the CS128LF speaker cabinet, as shown in the
following figure. These bolts are preinstalled in the CS128LF cabinet.
3. Reinstall the M10 bolts with the M10 washers that are included with the BKT.FLR kit, securing the BKT.FLR
brackets, and then tighten the M10 bolts to 8-10 Nm (8.9 -lb, 106 in-lb).
4. Secure the CS128LF to the building structure with installer-provided mounting hardware.
Assembling and Securing the CS128LF
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Figure 10: Securing the CS128LF
Note: Proper selection and installation of mounting hardware is the exclusive responsibility of the
installer. We recommend using M10 bolts and a serviceable thread-locking compound (for
example, Loctite 243). We also recommend applying acoustic or other nonhardening caulk to the
bottom side of the bracket to isolate speaker vibration from the building structure.
3.2 Installing the optional full-range crossover into the CS126MH
Instructions are provided for installing the optional full-range crossover (PXO.126) into the CS126MH for
System 126 single amplifier channel operation. For this configuration, you need to purchase the optional full-
range crossover from Dolby.
About this task
The following tools are required:
• 3 mm hex driver or wrench
• Phillips head screwdriver
• Flat head screwdriver
Procedure
Assembling and installing System 126
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1. Remove the six 3 mm hex-drive screws that secure the CS126MH top access panel, and then place the
screws in a safe place.
2. Carefully remove the access panel by gently prying it up with the flat head screwdriver. Once removed,
flip the access panel over to expose its back side where you will secure the full-range crossover.
Figure 11: Remove CS126MH access panel
3. Remove the full-range crossover from its packaging and place it on the back side of the CS126MH access
panel, lining it up with the indentations.
Note: The full-range crossover fits into all the CS126MH access panel indentations only in one
orientation.
4. Use the six Phillips-head wood screws provided in the PXO.126 kit to secure the full-range crossover to
the bottom side of the access panel in all six locations.
Installing the optional full-range crossover into the CS126MH
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Figure 12: Mount optional crossover in CS126MH access panel
5. Look through the open area where the panel was removed. On one side of the speaker is an internal
crossover, which splits the signal between the CS126MH high and mid drivers and the input plate.
6. Locate the input plate (where the wiring connection is made to the outside of the speaker). There is one
connector bundle with wires going to the internal crossover (red and black wire color).
7. Grip the wire harness connector on the back side of the input plate, and then release it by pushing down
on the top side of the connector tab and pulling it outward.
Figure 13: Back side of CS126MH input plate (rear panel removed for illustration)
Assembling and installing System 126
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