JBL GTO SERIES 301.1
CAR AMPLIFIER
TROUBLESHOOTING AND CIRCUIT DIAGRAM
CONNECTIONS
The GTO subwoofer amplifiers are single-channel
amplifiers. There are two sets of terminals to make it easy to connect multiple
woofers. Either set of (+/–) terminals may be used when connecting woofers. To
the right are two application diagrams to help plan your subwoofer system
installation. Figure show how to configure the GTO subwoofer amplifiers
NOTE: Minimum speaker load is 2 ohms.
NOTE: Minimum speaker load is 2 ohms.
SETTING THE CROSSOVER(S)
Determine your system plans and set the crossover mode switch accordingly. Initially set the crossover frequency control midway. While listening to music, adjust the crossover for the least perceived distortion from the speakers, allowing them to reproduce as much bass as possible. Systems using a separate subwoofer set the crossover mode to HP (high pass) for your full-range speakers. Adjust the crossover frequency to limit bass and provide increased system volume with less distortion. For subwoofers, choose the highest frequency that removes vocal information from the sound of the subwoofer.
Determine your system plans and set the crossover mode switch accordingly. Initially set the crossover frequency control midway. While listening to music, adjust the crossover for the least perceived distortion from the speakers, allowing them to reproduce as much bass as possible. Systems using a separate subwoofer set the crossover mode to HP (high pass) for your full-range speakers. Adjust the crossover frequency to limit bass and provide increased system volume with less distortion. For subwoofers, choose the highest frequency that removes vocal information from the sound of the subwoofer.
SETTING INPUT SENSITIVITY
1. Initially turn the INPUT LEVEL control(s) to minimum (counter clockwise).
2. Reconnect the (–) negative lead to the vehicle’s battery. Apply power to the audio system and play a dynamic music track.
3. On the source unit, increase the volume control to 3/4 volume. Slowly increase the INPUT LEVEL control(s) toward three o’clock until you hear slight distortion in the music. Then reduce the INPUT LEVEL slightly until distortion is no longer heard.
NOTE: After the source unit is on, red LEDs (on the top panel) will light, indicating the amplifier is on. If not, check the wiring, especially the remote connection from the source unit.
1. Initially turn the INPUT LEVEL control(s) to minimum (counter clockwise).
2. Reconnect the (–) negative lead to the vehicle’s battery. Apply power to the audio system and play a dynamic music track.
3. On the source unit, increase the volume control to 3/4 volume. Slowly increase the INPUT LEVEL control(s) toward three o’clock until you hear slight distortion in the music. Then reduce the INPUT LEVEL slightly until distortion is no longer heard.
NOTE: After the source unit is on, red LEDs (on the top panel) will light, indicating the amplifier is on. If not, check the wiring, especially the remote connection from the source unit.
TROUBLESHOOTING
No audio (POWER LED is off)
No voltage at BATT+ or REM terminals, or bad
or no ground connection.
Check voltages at amplifier terminals with VOM
No audio (PROTECT LED flashes every 4 seconds)
DC voltage on amplifier output
Check the amplifier output transistor and
drivers
No audio (PROTECT LED is on)
Amplifier is overheated
Make sure amplifier cooling is not blocked at
mounting location; verify speaker system impedance is within specified limits
No audio (PROTECT and POWER LEDs flash)
Voltage less than 9V on BATT+ connection
Check vehicle charging system for defective
voltage regulator
No audio (PROTECT LED is on)
Voltage more than 16V or less than 8.5V on BATT+
connection regulator
Check vehicle charging system for defective
voltage
Distorted audio
Input sensitivity is not set properly, or
amplifier or source unit is defective
Check INPUT LEVEL setting; or check speaker
wires for shorts or grounds
Distorted audio and PROTECT LED flashes
Short circuit in speaker or wire
Remove speaker leads one at a time to locate
shorted speaker or wire, then repair
HIGH FREQUENCY INVERTER POWER SUPPLY CIRCUIT
USING - USING - NMJ13600 - NMJ2068 TIP35C - TIP36C
PRE AMP AND POWER AMP CIRCUIT
USING - NMJ13600 - NMJ2068 TIP35C - TIP36C
CLICK ON THE IMAGES TO ZOOM IN
