why yOu shOuld Pay aTTenTiOn TO This Owner’s Manual
The performance of your vehicle’s audio system depends as much on quality installation and setup as it does on
quality gear. Of course, these new JBL® GTO amplifiers are bulletproof performers that are built using the highest
quality components, and will outperform any competing product on the test bench. To make sure you extract all
the performance possible from your new amp, whether you install it yourself or have a professional install it for you,
we’ve incorporated some new features that make setup simple and precise and ensure you get all the power and
performance you’ve paid for.
WHAT MAKES THESE AMPLIFIERS DIFFERENT
All amplifiers include some signal processing functions, level setting controls and other switches and connectors that
make it possible to hook the amp up to just about any existing system. However, with many amplifiers, considerable
technical expertise is required to make the best use of those connectors, switches and controls to get powerful noisefree sound. JBL GTO amplifiers include Simple Setup designed to make it easy for you to get all the noise-free power
your amp is capable of delivering.
WHAT MAKES INPUT SETUP EASY
GTO Amplifiers include adapters for connecting almost any analog signal and feature built-in Gain Indicator LEDs and
a setup CD that makes precision adjustment simple, no matter your level of experience. The setup of GTO amplifiers is
a little different than amplifiers you may have installed in the past, so please read this owner’s manual before you
begin. If you’re an experienced installer, skipping ahead is OK, but please don’t skip Setup Procedure, on
page 8.
So we can better serve you should you require warranty service, please retain your original sales receipt and register
your GTO-5EZ or GTO-3EZ online at www.jbl.com.
included iTeMs
The following items are included in the packaging. If any of these items are missing, please contact your authorized
JBL dealer, or JBL customer service at www.jbl.com.
GTO Series
Amplifier
Bare Wire-to-RCA Adapters
(5 in GTO-5EZ; 3 in GTO-3EZ)
Setup CD
lOcaTiOn and MOunTinG
INSTALLATION WARNINGS AND TIPS
IMPORTANT: Disconnect the vehicle’s negative (–) battery terminal before beginning the installation.
• Always wear protective eyewear when using tools.
• Check clearances on both sides of a planned mounting surface. Be sure that screws or wires will not puncture
brake lines, fuel lines or wiring harnesses, and that wire routing will not interfere with the safe operation of the
vehicle.
• When making electrical connections, make sure they are secure and properly insulated.
• If you must replace any of the GTO-5EZ/GTO-3EZ’s fuses, be sure to use the same type of fuse and current rating
as that of the original.
INSTALLATION LOCATION
Amplifiers need air circulation to stay cool. Select a location that provides enough air for the amp to cool itself.
• Suitable locations are under a seat (provided the amplifier doesn’t interfere with the seat adjustment mechanism),
in the trunk, or in any other location that provides enough cooling air.
• Do not mount the amplifier with the heatsink facing downward, as this interferes with the amplifier’s convection
cooling.
• Mount the amplifier so that it will not be damaged by the feet of backseat passengers or shifting cargo in the trunk.
• Mount the amplifier so that it remains dry – never mount an amplifier outside the car or in the engine compartment.
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MOUNTING THE AMPLIFIER
NOTE: You may find it more convenient to make all of the connections to the amplifier before you permanently mount
it to the vehicle.
Before mounting the amplifier you must remove the two end caps to expose the mounting holes and the connections.
Using a Phillips screwdriver, remove the attachment screws and then the end caps, as shown in the illustration. Put
the screws in a safe place, so you can use them to reattach the end caps after you have made all the connections to
the amplifier.
NOTE: Before you permanently mount the amplifier, read Auto Turn-On Switch, below, to determine the setting of the
switch, which is located on the amplifier’s bottom panel.
1. Select a suitable mounting location as described above.
2. Using the amplifier as a template, mark the locations of the mounting holes on the mounting surface.
3. Drill pilot holes in the mounting surface.
4. Attach the amplifier to the mounting surface with four appropriate mounting screws of your own choice. We
suggest using #8 Phillips-head sheet metal screws. Make sure the amplifier is mounted securely.
Englis h
cOnnecTiOns
IMPORTANT: Disconnect the vehicle’s negative (–) battery terminal before beginning the installation.
If you have not already done so, remove the two end caps that cover the amplifier’s connectors as explained in
Mounting the Amplifier, above. This will provide easier access to all of the amplifier’s connectors.
AUTO TURN-ON SWITCH
No remote turn-on connection is necessary because GTO amplifiers include signal-sensing turn-on, which will turn
the amplifier on when it receives an audio signal at any of its input connectors. The amplifier will automatically turn off
approximately five minutes after the input signal ceases.
If your audio system’s source unit includes a remote turn-on wire and you would prefer to use it, the amplifier
will sense that you’ve used a remote turn-on wire and that connection will override the signal-sensing turn-on. If
necessary, you can defeat the signal-sensing turn-on circuit by moving the Auto Turn-On switch to the “Off” position.
www.jbl.com
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CONNECTING THE POWER AND GROUND
The GTO series amplifiers are capable of delivering extremely high power levels, and require a heavy-duty and
reliable connection to the vehicle’s electrical system to achieve optimal performance. Please adhere to the following
instructions carefully.
Using the Connectors
GTO series amplifiers use the same type of screw terminals for power and speaker connections. This type of terminal
is easy to use, provides superior current transfer and allows the easy connection of large-gauge wire.
To use the connectors, use a Phillips screwdriver to loosen the connector’s set screw, insert the bare wire and tighten
the set screw to secure the wire in the connector.
Loosen
Screw
Insert
Wire
Tighten
Screw
Ground Connection
Connect a wire (minimum 6AWG – 13.2mm2 – for the GTO-5EZ; minimum 8AWG – 8.4mm2 – for the GTO-3EZ) from
the amplifier’s GND terminal directly to a solid point on the vehicle’s chassis. For a good connection, use sandpaper
to clear the paint from the metal surface at this chassis location. Use a star-type lock washer to secure the wire’s
connection.
Power
Connectors
Audio System Head Unit
Remote Turn-On (optional)
>
#18 AWG (0.82mm2) Wire
+12V
>
#6AWG (13.2mm2) Wire – GTO-5EZ
>
90A Fuse (GTO-5EZ)
70A Fuse (GTO-3EZ)
18"
(46cm)
#8AWG (8.4mm2) Wire – GTO-3EZ
Chassis Ground
(bare metal)
>
#6AWG (13.2mm2) Wire – GTO-5EZ
>
#8AWG (8.4mm2) Wire – GTO-3EZ
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