GT5-A604 - JBL Car Audio Service Manual (repair manual). Page 5

Read JBL GT5-A604 Service Manual online

Installation Warnings and Tips
• Disconnect the negative (–) lead from your vehicle’s
battery.
• At the installation sites, locate and make a note of
all fuel lines, hydraulic brake lines, vacuum lines
and electrical wiring. Use extreme caution when
cutting or drilling in and around these areas.
• Choose a safe mounting location away from moisture. 
• Make sure there is sufficient air circulation at the
mounting location for the amplifier to cool itself.
• Mount the amplifier, using the supplied hardware.
Specifications
• 60W RMS x 4 channels @ 4 ohms and 
≤1% THD + N*
• 80W RMS x 4 channels @ 2 ohms, 14.4V supply and
≤1% THD + N*
• 160W RMS x 2 channels @ 4 ohms, 14.4V supply and
≤1% THD + N*
• THD + N: 0.05% (rated power @ 4 ohms)*
• Signal-to-noise ratio: 85dBA 
(reference 1W into 4 ohms)*
• Signal-to-noise ratio: 102dBA 
(reference rated power into 4 ohms)
• Frequency response: 10Hz – 100kHz (–3dB)*
• Total peak power: 640 watts
* CEA-2006A-compliant
Speaker Output Connectors
• Connect the speakers to these terminals,
observing proper polarity:
• Four-channel operation: Connect the front 
left speaker to the Front L+ and L– terminals,
and the front right speaker to the Front R+ and
R– terminals. Repeat for rear speakers, using
the Rear L+ and L– terminals, and the Rear R+
and R– terminals.
• Three-channel operation: Connect the stereo
speakers to the Front terminals, as above.
Connect the single speaker into which the
amplifier’s rear channels will be bridged to the
Rear R+ and Rear L– terminals. 
• Two-channel (bridged) operation: Connect one
speaker to the Front R+ and Front L– termi-
nals. Connect the other speaker to the Rear
R+ and Rear L– terminals.
• Minimum speaker impedance for stereo opera-
tion is 2 ohms. Minimum speaker impedance for
bridged operation is 4 ohms.  
Fuses
• Replace only with the same type and rating.
Power Input Connectors 
• +12V: Connect to the positive terminal of the
vehicle’s battery. 8 AWG wire is recommended.
Install an appropriate fuse holder and fuse (40A
minimum) within 18 inches of the battery. Make
sure the wire is not damaged or pinched during
installation. Install protective grommets when
routing wires through the firewall or other sheet
metal. 
• GND: Connect to the vehicle’s chassis. Refer to
the picture below. 
• REM: Connect to the “Remote Out” lead from
the source unit or to a source of switched 
12V+ (ACC).
Aux Output Connectors (RCA)
• Summed, nonfiltered pass-through output. 
Front right and rear right inputs are combined
and sent to the right AUX output. Front left 
and rear left inputs are combined and sent 
to the left AUX output. Connect to the input 
of an additional subwoofer amplifier. 
Front Input Connectors (RCA)
• Connect to the front RCA outputs from the
source unit or signal processor.
Front Input-Level Control
• Used to match the front input level of the 
amplifier to the output level of the source unit.
• See F for the adjustment procedure.
Front Crossover-Frequency Control
• 12dB/octave crossover, variable from 
32Hz to 320Hz.
• See G for the adjustment procedure.
Front Crossover-Filter Selector
• LP: Select for subwoofer(s).
• FLAT: Select for full-range speakers when 
no subwoofer will be used in the system.
• HP: Select for midrange speakers or 
full-range speakers when a subwoofer is 
used in the system.
Power On LED
• Illuminated when the amplifier is on.
Protect LED
• Illuminated under any of the following fault 
conditions: battery over/under voltage, short 
circuit in speaker wires, amplifier is too hot,
amplifier’s output circuit has failed (DC voltage
present in the amplifier’s output).
Rear Bass-Boost Control
• Provides up to 6dB of boost at 50Hz. Set 
the Bass-Boost control according to your 
preference, being careful not to apply enough
boost to damage the speaker(s).
Rear Crossover-Frequency Control
• 12dB/octave crossover, variable from 
32Hz to 320Hz. 
• See adjustment procedure in G.
Rear Crossover-Filter Selector
• LP: Select for subwoofer(s).
• FLAT: Select for full-range speakers when 
no subwoofer will be used in the system.
• HP: Select for midrange speakers or 
full-range speakers when a subwoofer is 
used in the system.
Rear Input-Level Control
• Used to match the rear input level of the 
amplifier to the output level of the source unit.
• See F for the adjustment procedure.
Rear Input Connectors (RCA)
• Connect to rear RCA outputs from the source 
unit or signal processor.
Setting Input Level
Turn all Input-Level controls counterclockwise
to 6V (minimum).
With a dynamic music track playing, turn head
unit’s volume control to the 3/4 position.
Turn Front Input-Level control clockwise until
the music is so loud that it no longer sounds
clear (distortion is present in the output).
Turn Front-Input-Level control counterclock-
wise gradually, just until the music sounds
clear, once again.
Front-level input is now adjusted correctly.
Adjust Rear Input-Level control so that the 
level of the rear speakers is proportionate to 
the level of the front speakers, according to 
your preference.
Setting the Crossover
Crossover setting for 5" or larger full-range
speakers when no subwoofer is included in 
the system.
Crossover setting for midrange and/or 
full-range speakers when a subwoofer 
is included in the system.
Crossover setting for subwoofers.
Note: Acceptable frequency ranges indicated 
in gray.
GT5-A604 CAR AUDIO POWER AMPLIFIER 
OWNER’S MANUAL
Factory Bolt
Ring Connector
Ground Wire
Note: Remove any paint
below ring connector.
Star Washer
This product is designed for mobile applications and is not 
intended for connection to the mains.
A valid serial number is required for warranty coverage.
Features, specifications and appearance are subject to change
without notice.
4
 
 
GT5-A604 
            
 
 
 
 
 
 
 
  
 
 
Page of 19
Display

Click on the first or last page to see other GT5-A604 service manuals if exist.