JBL A302GTi (serv.man3) Service Manual ▷ View online
A302GTI
2 CHANNEL
AUTOMOTIVE AMPLIFIER
TECHNICAL MANUAL
JBL CONSUMER PRODUCTS
250 CROSSWAYS PARK DRIVE, WOODBURY, NY 11797
1-800-336-4JBL(4525) WWW.JBL.COM
250 CROSSWAYS PARK DRIVE, WOODBURY, NY 11797
1-800-336-4JBL(4525) WWW.JBL.COM
SPECIFICATIONS
Specifications .........................................................1
Features .................................................................2
Test Conditions and Notes ......................................2
Controls and Connections .....................................3
Mounting the amplifier............................................3
Typical System Configuration (Wiring) ....................4
Printed Circuit Boards (Top View)...............5~6
Features .................................................................2
Test Conditions and Notes ......................................2
Controls and Connections .....................................3
Mounting the amplifier............................................3
Typical System Configuration (Wiring) ....................4
Printed Circuit Boards (Top View)...............5~6
Parts Lists........................................................7~9
Block Diagrams....................................................10
Block Diagrams....................................................10
Packaging Exploded View................................13~15
Integrated Circuit Diagrams...................................11
Transistor Diagrams..............................................12
Schematic Diagrams...................
....................16~18
Amplifier Exploded View........................................19
Number of Channels . . . . . . . . . . . . . . . . . . .
4 Ohms . . . . . . . . . . . . . . . . . . . . .
2 Ohms . . . . . . . . . . . . . . . . . . . . .
T.H.D. @ 4 Ohms rated Power . . . . . . . . . . . . .
Frequency Response . . . . . . . . . . . . . . . . . .
Signal to noise Ratio . . . . . . . . . . . . . . . . . . .
Fuse size. . . . . . . . . . . . . . . . . . .
Input Leve Sensitivity. . . . . . . . . . . . . . .
Length . . . . . . . . . . . . . . . . . . . . . . . . . . .
Width . . .
. . . . . . . . . . . . . . . . . . . . . . . .
Depth . . . . . . . . . . . . . . . . . . . . . . . . . . .
Length . . . . . . . . . . . . . . . . . . . . . . . . . . .
Width . . . . . . . . . . . . . . . . . . . . . . . . . . .
Depth . . . . . . . . . . . . . . . . . . . . . . . . . . .
2
150W
300W
0.03%
10Hz ~ 40KHz
110 dB
80A
250mV - 4V
1ohm
14 13/16
10 3/16
2 11/16
376
274
67.5
External Dimensions (Inches)
External Dimensions (mms)
JBL continually strives to improve its products. New materials, production methods and design refinements are
introduced into existing models without notice as a routine expression of our design philosophy. For this reason,
GTI Series Multichannel Automotive Amplifiers may differ in some respects from their published specifications
and descriptions, but will always equal or exceed the original specifications unless otherwise stated.
introduced into existing models without notice as a routine expression of our design philosophy. For this reason,
GTI Series Multichannel Automotive Amplifiers may differ in some respects from their published specifications
and descriptions, but will always equal or exceed the original specifications unless otherwise stated.
1
2 Channel Automotive Amplifier
A302GTI
Controls and connections
Minimum Speaker Impedance . . . . . . . . . . . . .
Test Conditions and Notes
2-Channel Operation
Floating Ground Factory - Head - Unit Speaker - Level input
Variable Input Sensitivity (250mV - 4V)
Fully Complementary Output Stage with Class-AB Voltage Amplification
Gold-plated Power, Input and Output Connectors
2-Ohm Stable (Stereo)
All tests to be done, unless otherwise specified, from 10Hz to 40KHz at 14.4V DC into 4 ohm loads and adjust
the units gain so that with a .250 volt input signal the unit is at its maximum rated output. All measurements
will be done using an Audio precision system one and the supply voltage.
the units gain so that with a .250 volt input signal the unit is at its maximum rated output. All measurements
will be done using an Audio precision system one and the supply voltage.
An B+ line voltage of 14.4V DC shall be applied to the unit under test for all measurements unless otherwise
specified. The voltage applied to the unit shall be measured at the power connection on the Amplifier.
specified. The voltage applied to the unit shall be measured at the power connection on the Amplifier.
Signal Source
Unless otherwise specified, all tests shall be conducted with the Audio Signal Generator output configured to
be balanced, less than or equal to 50 ohm source impedance, and floating. The signal source "GND" shall be
connected to the Amplifier PWR GND at the Amplifier.
Unless otherwise specified, all tests shall be conducted with the Audio Signal Generator output configured to
be balanced, less than or equal to 50 ohm source impedance, and floating. The signal source "GND" shall be
connected to the Amplifier PWR GND at the Amplifier.
Output Load
Unless otherwise specified, all tests shall be conducted with 4 ohm resistive loads having less than 10%
reactive components at any frequency below 75KHz. Each resistor shall have a value that remains within 1%
while dissipating the rated output of the unit under test.
Unless otherwise specified, all tests shall be conducted with 4 ohm resistive loads having less than 10%
reactive components at any frequency below 75KHz. Each resistor shall have a value that remains within 1%
while dissipating the rated output of the unit under test.
Power Indicator LED steadily illuminates for normal operation. LED blinks when
protection circuitry is engaged, and during power up.
protection circuitry is engaged, and during power up.
2
A302GTI
Features
2 Channel Automotive Amplifier
Controls and Connections
Controls and Connections
Mounting the Amplifier
2. Speaker Output Connector - Connect speaker
wiring to these connectors. See wiring instruc-
tions on page 4 for more information.
3. Fuse - Three 20 Amp ATC type Fuses.
The JBL GTI Series amplifiers can be mounted in virtually any location inside the vehicle.
However, make sure to keep the amplifier away from heater vents or ducts.
However, make sure to keep the amplifier away from heater vents or ducts.
1. At the chosen site, use the amplifier as a mounting template and mark the locations of the
four mounting holes.
four mounting holes.
2. Drill a small pilot hole at each marked location.
3. Mount the amplifier and securely tighten the mounting screws.
4. Power Connection for 12V+, GND and REM
connections for power wires. See wiring instruc-
tions on page 4 for more information.
5. Input-Level Control - Adjusts input sensitivity
for pre-amp level and speaker level inputs.
6. The electronic crossover is a 24dB/oct.
Low pass filter which can be Set at any frequency
between 40Hz and 400Hz.
7. The electronic crossover is a 24dB/oct.
High pass filter which can be Set at any frequency
between 40Hz and 400Hz.
8. Stereo and bridged selector switch.
9. Crossover selector switch-Low pass filter (LPF),
High pass filter (HPF) or it may be defeated (FLAT).
10. External Capacitor(Optional)
2 Channel Automotive Amplifier
3
A302GTI
SPEAKER OUTPUTS
FUSE 20Ax3
+BATT
+BATT
REM
POWER
CAPTAP
GND
GND
- + - +
X-OVER FREQUENCY
R
L
INPUT
LEVEL
LEVEL
4V 250mV
40Hz 400Hz
40Hz 400Hz
HPF
FREQ
FREQ
LPF
FREQ
FREQ
.
.
.
.
.
.
A302GTI
7
9
8
2
3
10
4
5
1
6
ST BR
HPF FLAT LPF
REMOTE
1. Preamp-Level Input Connector - Connects to
line-level output from the source unit.
line-level output from the source unit.
