Extron electronics SF 8CT SUB User manual

User Guide
SF 8CT SUB
Speakers
SoundField 8” In-Ceiling Subwoofer
68-3512-01 Rev. C
07 21


Copyright
© 2021 Extron. All rights reserved. www.extron.com
Trademarks
All trademarks mentioned in this guide are the properties of their respective owners.
The following registered trademarks (®), registered service marks (SM), and trademarks (TM) are the property of RGBSystems, Inc. or Extron (see the
current list of trademarks on the Terms of Use page at www.extron.com):
Registered Trademarks (®)
Extron, Cable Cubby, ControlScript, CrossPoint, DTP, eBUS, EDID Manager, EDID Minder, eLink, Flat Field, FlexOS, Glitch Free, GlobalConfigurator,
GlobalScripter, GlobalViewer, Hideaway, HyperLane, IPIntercom, IPLink, KeyMinder, LinkLicense, LockIt, MediaLink, MediaPort, NAV,
NetPA, PlenumVault, PoleVault, PowerCage, PURE3, Quantum, ShareLink, Show Me, SoundField, SpeedMount, SpeedSwitch, StudioStation,
SystemINTEGRATOR, TeamWork, TouchLink, V‑Lock, VideoLounge, VN‑Matrix, VoiceLift, WallVault, WindoWall, XPA, XTP, XTPSystems, and ZipClip
Registered Service Mark(SM) : S3 Service Support Solutions
Trademarks (™)
AAP, AFL (Accu‑RATEFrameLock), ADSP(Advanced Digital Sync Processing), AVEdge, CableCover, CDRS(ClassD Ripple Suppression),
CodecConnect, DDSP(Digital Display Sync Processing), DMI (DynamicMotionInterpolation), DriverConfigurator, DSPConfigurator, DSVP(Digital
Sync Validation Processing), EQIP, Everlast, FastBite, Flex55, FOX, FOXBOX, IP Intercom HelpDesk, MAAP, MicroDigital, Opti‑Torque,
PendantConnect, ProDSP, QS‑FPC(QuickSwitch Front Panel Controller), RoomAgent, Scope‑Trigger, SIS, SimpleInstructionSet, Skew‑Free,
SpeedNav, Triple‑Action Switching, True4K, True8K, Vector™ 4K, WebShare, XTRA, and ZipCaddy

FCC Class B Notice
NOTE: This device complies with part 15 of the FCC rules. Operation is subject to the
following two conditions: (1) This device may not cause harmful interference, and (2)
This device must accept any interference received, including interference that may
cause undesired operation.
This equipment has been tested and found to comply with the limits for a Class B digital
device, pursuant to part15 of the FCC rules. These limits provide reasonable protection
against harmful interference in a residential installation. This equipment generates, uses,
and can radiate radio frequency energy and, if not installed and used in accordance with
the instructions, may cause harmful interference to radio communications. There is no
guarantee that interference will not occur. If this equipment does cause interference to radio
or television reception, which can be determined by turning the equipment off and on, you
are encouraged to try to correct the interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which the
receiver is connected.
• Consult the dealer or an experienced radio/TV technician for help.
In order to maintain compliance with FCC regulations, shielded cables must be used with
this equipment. Operation with non-approved equipment or unshielded cables is likely to
result in interference to radio and TV reception. The user is cautioned that changes and
modifications made to the equipment without the approval of the manufacturer could void
the user’s authority to operate this equipment.
NOTE: For more information on safety guidelines, regulatory compliances, EMI/EMF
compatibility, accessibility, and related topics see the Extron Safety and Regulatory
Compliance Guide on the Extron website.

Conventions Used in this Guide
Notifications
The following notifications are used in this guide:
WARNING: Potential risk of severe injury or death.
AVERTISSEMENT : Risque potentiel de blessure grave ou de mort.
ATTENTION:
• Risk of property damage.
• Risque de dommages matériels.
NOTE: A note draws attention to important information.
Specifications Availability
Product specifications are available on the Extron website, www.extron.com.
Extron Glossary of Terms
A glossary of terms is available at http://www.extron.com/technology/glossary.aspx.

viiSF 8CT SUB • Contents
Contents
Introduction ................................................ 1
About this Guide.................................................. 1
About the SF 8CT SUB ....................................... 1
Features .............................................................. 2
Installation in a Suspended Ceiling............... 3
Installation Considerations ................................... 3
Preparing the Installation Location ....................... 3
Configuring the Speaker ...................................... 5
Mounting the Speaker ......................................... 8
Installation in a Hard Ceiling ...................... 13
Preparing the Installation Location ..................... 13
Configuring the Speaker .................................... 13
Mounting the Speaker ....................................... 14
Reference Information............................... 18
Painting the Speaker Grille................................. 18
Troubleshooting: Signal Test Points.................... 19
Testing Source Signal (All Configurations)....... 19
Testing the Impedance (Loop-Through
Configuration Only) ....................................... 19

SF 8CT SUB • Contents viii

SF 8CT SUB User Guide • Introduction 1
Introduction
• About this Guide
• About the SF 8CT SUB
• Features
About this Guide
This guide describes the Extron SF 8CT SUB, a subwoofer that is typically installed above
a suspended ceiling with limited vertical clearance. This guide describes how to install,
operate, and configure the subwoofer.
About the SF 8CT SUB
The SF 8CT SUB (see figure1 on the next page) is a plenum-rated, 8 ohm, direct-radiating,
ported subwoofer, featuring a 14.5” (368 mm) composite back can for use in plenum-rated
ceiling environments.
The subwoofer has a frequency range of 40 Hz to 325 Hz -10 dB, half space, LPF enabled.
The SF 8CT SUB is compatible with any Extron low impedance amplifier with sufficient
output drive power. The unit is UL 2043 Listed for use in air-handling spaces.
The subwoofer is intended for use in a bi-amplified system. Separate amplifiers should
power the low and high frequencies.
ATTENTION:
• The SF 8CT SUB is UL Listed for use in plenum airspaces: meets UL 2043 for
heat and smoke release.
• Le SF 8CT SUB est certifié UL pour une utilisation dans des espaces de plenum:
il est conforme à la norme UL 2043 relative à l’évacuation de la chaleur et de la
fumée.
• Suitable for use in environmental air space in accordance with Section 300-22(C)
of the National Electrical Code, and Sections 2-128, 12-010(3) and 12-100 of the
Canadian Electrical Code, Part 1, CSA C22.1.
• The product has been additionally investigated to UL 2043, “Fire Test for Heat
and Visible Smoke Release for Discrete Products and Their Accessories Installed
in Air-Handling Spaces”.
• Adapté à des espaces environnementaux de plenum, conformément à la section
300-22(C) du National Electrical Code américain et aux sections 2-128, 12-
010(3) et 12-100 du Code canadien de l’électricité, Partie 1, CSA C22.1.
• Le produit est par ailleurs conforme à la norme UL 2043 « Fire Test for Heat and
Visible Smoke Release for Discrete Products and Their Accessories Installed in
Air-Handling Spaces ».

SF 8CT SUB User Guide • Introduction 2
Figure 1. Typical SF 8CT SUB Application
Features
• 8” (203 mm) low frequency driver in a tuned port enclosure
• Frequency Range: 440 Hz to 325 Hz -10 dB, half space, LPF enabled
• 100 watts continuous pink noise
• 200 watts continuous program
• 8 ohm direct or 70/100 volt operation —
• 8 ohm direct
• 70 volt: 64, 32, 16, and 8 watt selectable
• 100 volt: 64, 32, and 16 watt selectable
• Selectable 120 Hz Low Pass Filter — 6 dB per octave
• UL 2043 plenum rated
• Magnetically attached grille with a thin bezel for a refined appearance
• Locking arms support ceilings up to 2.25 inches (57.1 mm) thick.
• Grille and bezel are white and can be painted to match any environment
• Modular V-rail and folding C-ring kit included
• Side oriented cable/conduit access plate can be for connection clearance
• Opti-Torque indicator rings prevent overtightening of locking arm screws
• Four locking arms for quick ceiling installation
• UL 1480 listed for safety
• 5-year parts and labor warranty
1
LAN
OUTPUTSINPUTS
ACTIVITY
CONFIG EXP
USB
LAN 1
LAN 2
DMP 64 Plus
DIGITALMATRIX PROCESSOR
123456 1234
CLIP
SIGNAL
CLIP
SIGNAL
XPA U 1004SB
LIMITER/PROTECT
SIGNAL
OVER
TEMP 1 2 3 4
Dante/PoE Ethernet Ethernet Ethernet/PoE
Ch. 1 & 2
Bridged 70V
Ch. 3 & 4
Bridged 8Ω
200 Watt
AudioAudioAudio
Ceiling Mic Array
Extron
TLP Pro 1025T
10" Tabletop TouchLink
Pro Touchpanel with
LinkLicense for TLP
Control Processor
Extron
SF 3CT LP
Ceiling Speakers
Extron
DMP 64 Plus C V AT
Digital Matrix Processor
Extron
XPA U 1004 SB
Power Amplier
Extron
SF 8CT SUB
Ceiling
Subwoofer
AV Sources
Audio
Audio

SF 8CT SUB User Guide • Installation in a Suspended Ceiling 3
Installation in a
Suspended Ceiling
This section describes the installation and the operation of the SF 8CT SUB in a suspended
ceiling (having ceiling tiles). Topics in this section include:
• Installation Considerations
• Preparing the Installation Location
• Configuring the Speaker
• Mounting the Speaker
Installation Considerations
WARNING: Potential risk of severe injury.Installation and service must be
performed by authorized personnel only.
AVERTISSEMENT : Risque potentiel de blessure grave ou de mort. L’installation et
l’entretien doivent être effectués par le personnel autorisé uniquement.
• All wiring and electrical connections must conform to all applicable building codes and
local ordinances.
• Installation in a plenum-rated environment requires plenum-rated cable or conduit.
• If using secondary support cables, the installer provides the cables.
Preparing the Installation Location
1. Power down all attached devices before proceeding.
2. Ensure that there is sufficient clearance above the ceiling tile for the unit to be installed.
3. Cut a hole for the speaker. Use the provided cutout template to outline the hole to be
cut in the ceiling tile as described below.
a. Remove the ceiling tile.
b. To find the center of the tile, use a tape measure to measure the space between
two opposite corners, and mark the half-way point.
c. Position the center hole of the cutout template directly over the center of the tile
that you marked in step3b.
d. Using the provided cutout template, trace a circle around the cutout template.
e. Cut out the circle traced on the ceiling tile.
f. Replace the tile in the ceiling.
step 3

SF 8CT SUB User Guide • Installation in a Suspended Ceiling 4
4. Attach two V-rails and one C-ring across the tile above the hole cut in step 3, as shown
below:
a. Assemble two V-rail half sections as follows: fit the tab of one end into the slot of
the other end, then open the V-rail until it locks together (see figure 2). Repeat this
procedure for the other V-rail.
Figure 2. Assembling the V-rails
b. Remove a ceiling tile adjacent to the tile with the hole.
c. Place both assembled V-rails on the cut ceiling tile and position them equally on
either side of the hole. The ends of the V-rails go over the ceiling grid.
Position the C-ring assembly on the two V-rails so that the C-ring is centered over
the hole, as shown below.
C-ring
V
-rail
Figure 3. Positioning the C-ring assembly on the V-rails
d. Secure the C-ring to the V-rails using four screws.
5. Route the speaker wires through the ceiling tile hole.
2
step 4b
3

SF 8CT SUB User Guide • Installation in a Suspended Ceiling 5
Configuring the Speaker
1. Configure the locking arms for thicker ceilings (optional).
Four speaker locking arms are used to secure the speaker to ceiling tiles up to
2.25 inches (5.72 cm) thick. The locking arms are equipped with removable inserts to
accommodate ceiling tiles of up to 1.5 inches (3.81 cm) in thickness. For ceiling tiles
thicker than 1.5 inches, the locking arm inserts must be removed.
To remove the inserts:
a. Using a screwdriver, rotate the locking arm so that the insert can be accessed.
Figure 4. Accessing the locking arm insert
b. Use a small screwdriver to pry and separate the insert from the locking arm, as
shown below.
Figure 5. Prying off the locking arm insert
c. Repeat this process for the remaining three locking arms.
d. Rotate all four locking arms back into the speaker.
4
5

SF 8CT SUB User Guide • Installation in a Suspended Ceiling 6
2. Configure the cable/conduit access plate and captive screw connector:
Loosen the two side access plate screws and remove the plate before wiring the
speaker.
To remove the plate:
a. Lift the cover up.
b. Remove the terminal cover.
Figure 6. Removing the cable/conduit access plate
3. Configure the access plate:
• If not using conduit: Route the speaker wires through the cable clamp.
• If using conduit: Remove the cable clamp and install the conduit into the plate
opening. Secure the conduit to the plate with the locking nut and pull the speaker
wires from the conduit.
NOTE: The cover plate has an alternate hole available by removing the
knockout.
4. Strip 0.2 inches (5 mm) from the wire ends.
5. Attach the speaker wires to the captive screw connector depending on the
configuration, as illustrated by the following three methods.
6

SF 8CT SUB User Guide • Installation in a Suspended Ceiling 7
Wiring Multiple Speakers in Parallel
When a chain of speakers is wired this way, disconnecting
one speaker does not remove power from the remaining
speakers in the chain.
Number of Wires per
Connection Point
Maximum
Wire Gauge
1 12 AWG
2 16 AWG
4 18 AWG
Wire Gauge Table
Speaker 1 Speaker 2
IN
–
–
LOOP
–
–
IN
+
+
LOOP
+
+
(Black)
(Red) (Red)
(Red)
(Black)
(Black)
Power Amplifier
Speaker 1 Speaker 2
(Black)
(Red) (Red)
(Black)
Power Amplifier
(Black)
(Red)
Speaker 1
(Red)
(Black)
Power Amplifier
IN
–
–
LOOP
–
–
IN
+
+
LOOP
+
+
IN
–
–
LOOP
–
–
IN
+
+
LOOP
+
+
IN
–
–
LOOP
–
–
IN
+
+
LOOP
+
+
IN
–
–
LOOP
–
–
IN
+
+
LOOP
+
+
Wiring Multiple Speakers Using Loop-through
When a chain of speakers is wired this way, disconnecting
one speaker removes power from all downstream speakers.
Wiring a Single Speaker
1
2
3
Figure 7. Speaker Wiring Schemes
ATTENTION:
• Do not tin the wire leads before installing into the connector. Tinned wires
are not as secure in the connector and could be pulled out.
• Ne pas étamer les conducteurs avant de les insérer dans le connecteur.
Les câbles étamés ne sont pas aussi bien fixés dans le connecteur et
pourraient être retirés.
• When connecting multiple speakers in 8-ohm mode, be sure that
the combined rated impedance does not equal a value less than the
minimum rated impedance of the amplifier.
• Lors de la connexion de plusieurs enceintes en mode 8ohm, assurez
vous que le niveau d’impédance combinée ne soit pas équivalent à une
valeur inférieure à l’impédance minimum de l’amplificateur.
7

SF 8CT SUB User Guide • Installation in a Suspended Ceiling 8
6. Insert the captive screw plug into the four-pole receptacle of the speaker.
• Using a cable clamp on the access plate:
Figure 8. Using a cable clamp
• Using a conduit adapter on the access plate:
Flexible Conduit Adapter
Figure 9. Using a conduit adapter
7. Replace the access plate and tighten the two retaining screws.
8. Tighten the cable clamp if it was used.
Mounting the Speaker
The speaker can be Installed into rigid material (mineral tile, gypsum board, sheetrock, etc.)
or soft material, such as fiberglass.
1. Insert the speaker through the bottom of the hole in the ceiling tile that was cut in
step 3 on page3 (“Preparing the Installation Location”) with the wires out of the
way.
2. Clamp the speaker to the C-ring by using a Phillips screwdriver to tighten the four
locking arms to the C-ring (see figure 9).
8
9

SF 8CT SUB User Guide • Installation in a Suspended Ceiling 9
Figure 10. Clamping the speaker to the C-ring
Tightening the locking arms into rigid material:
For rigid material use the Opti-TorqueTM indicator ring as a tightening guide.
NOTE: Each of the four locking arm screws uses an Opti-Torque indicator ring. The
indicator releases a red plastic ring onto the screwdriver once the screw is
tightened to the correct torque. Stop tightening any further when this occurs to
avoid overtightening the locking arms to the C-ring.
Figure 11. Stop tightening when the red ring falls
ATTENTION:
• To avoid damaging the speaker locking arms, do not overtighten the four
screws.
• Ne pas trop serrer les quatre vis pour éviter d’endommager les bras de
verrouillage de l’enceinte.
Tightening the locking arms into soft material:
Because fiberglass ceilings and other soft materials are not as rigid as mineral tiles and
other hard materials, the Opti-Torque indicator ring must not to be used as a tightening
guide due to the risk of overtightening.
10
11

SF 8CT SUB User Guide • Installation in a Suspended Ceiling 10
ATTENTION:
• To avoid damaging or deforming soft ceiling material, tighten the locking arms
to secure the speaker, but short of causing the speaker to deform the flat
mounting surface of the ceiling, as seen from below.
• Afin de ne pas endommager ni d’altérer un plafond souple, serrez les bras de
verrouillage pour sécuriser l’enceinte, en veillant cependant à ce que l’unité
ne cause l’altération de la surface de montage plane du plafond, comme
illustré ci-dessous.
X
3. Connect secondary support lines to the support loops on the sides of the speaker
enclosure, as shown here.
Anchor end to suitable
secure points within the
solid and permanent
building structure.
Figure 12. Connecting a secondary support line
ATTENTION:
• Do not allow any slack in the secondary support lines.
• Ne laissez pas de mou au niveau du filin de sécurité secondaire.
4. Replace the adjacent ceiling tile that was removed in step 4b on page 4.
5. Set the rotary tap selector switch to the appropriate setting using a small screwdriver.
12

SF 8CT SUB User Guide • Installation in a Suspended Ceiling 11
ATTENTION:
• When setting the taps for a distributed (high impedance) system, do not tap
the system above the rated power of the amplifier.
• Lors de la mise en place des capteurs pour un système distribué (haute
impédance), n’exploitez pas le système au delà du niveau d’alimentation de
l’amplificateur.
• When connecting multiple speakers in 8-ohm mode, be sure that the
combined rated impedance does not equal a value less than the minimum
rated impedance of the amplifier.
• Lors de la connexion de plusieurs enceintes en mode 8ohm, assurez vous
que le niveau d’impédance combinée ne soit pas équivalent à une valeur
inférieure à l’impédance minimum de l’amplificateur.
Adjust the Tap Selector
100 V
64W
OFF
32W
16W
32W
16W
8W
64W
8Ω
8Ω
OFF
70 V
Figure 13. Setting the rotary tap selector switch
13

SF 8CT SUB User Guide • Installation in a Suspended Ceiling 12
6. Set the LPF selector switch to the appropriate setting using a small screwdriver. The
default position is LPF enabled. Disable the LPF if filtering is set on a device upstream of
the speaker. The LPF is fixed at 120 Hz.
Figure 14. Setting the LPF selector switch
7. Install the grille. Position the grille so that it covers the baffle of the speaker. Six small
magnets secure the grille in place.
Speaker Grille
Figure 15. Installing the speaker grille
NOTE: Specific test points can be used to troubleshoot speaker system problems.
Should problems be encountered, please see Troubleshooting: Signal Test
Points on page19.
14
15