Boston Acoustics GTA 502 User Manual

GTA  
High Performance Two and  
Four Channel Ampliers  
Connections and Controls  
GTA-502  
10  
11  
1
2
3
4
5
6
7
8
9
GTA-802  
10  
11  
1
2
3
4
5
6
7
8
9
GTA-504  
10  
11  
1
2
3
4
6
1
2
3
4
5
6
7
8
9
u
v
w
x
y
z
{
|
}
~
Speaker Level Input  
RCA Input (Left and Right)  
Gain (250mv to 5.0v - continuously variable)  
Crossover Frequency Adjustment (50Hz to 200Hz - continuously variable)  
Q-Tune Equalization Boost (+6dB @ 45Hz)  
Crosssover Filter Switch (HP / Off / LP)  
GTA-RSL Port (Remote Gain)  
Speaker Output Block (Left / Right) or (LF / RF / LR / RR on GTA-504)  
Status LED (Blue = Normal / Red = Fault Mode)  
Fuse (Replace with same value only, refer to specifications on page 2)  
Power Block (12v / Remote / Ground)  
Status LED  
The Boston Logo will illuminate “Blue” under normal operating conditions.  
The LED will illuminate “Red” during start-up and under fault conditions. If the  
LED is still red after start-up, please refer to troubleshooting on page 12.  
Speaker Level Input Cable  
GTA amplifiers offer a dedicated speaker level input for ease installation into  
factory systems when an RCA (low level) signal is not available. Wiring code for  
the cable is industry standard;  
White Solid = Left Positive  
Gray Solid = Right Positive  
White w/ Black Stripe = Left Negative  
Gray w/ Black Stripe = Right Negative  
Warning: Do not connect both Speaker Level and RCAs into the amplifier at the  
same time as damage to the amplifier may occur.  
3
Installation - General  
WARNING! Before driving the amplifier mounting screws through any surface,  
be sure of what is behind that surface. Check for the gas tank, brake lines, and  
any vehicle wiring harness. Never run wires outside or under the vehicle or  
where they could become broken or interfere with the safe operation of the  
vehicle.  
Before You Install  
Before you install the unit, disconnect the negative (–) battery cable in the  
engine compartment of the vehicle. Doing so will prevent damage to both the  
electrical system of the vehicle and the amplifier during installation.  
Battery and Charging System  
In order for the amplifier to function correctly, the electrical system of the  
vehicle should be professionally checked for overall electrical capacity. When  
used, the amplifier will increase the demand on the battery and alternator.  
Therefore, both should be thoroughly evaluated before installing the amplifier  
to ensure they are in normal operating condition and able to handle the  
increased demand the amplifier will present to the vehicle’s electrical system.  
Wire Routing  
Do not run the power wire near any low-level signals or audio cables such as  
the RCAs from the head unit. Noise can be introduced into the amplifier when  
this occurs. It is helpful to diagram the wire layout first before any installation  
is initiated.  
Choose the Mounting Location  
Plan your installation so that the amplifier is mounted where adequate  
ventilation is available. Never mount an amplifier in the engine compartment  
of a vehicle!  
Passenger and Trunk Compartment Mounting  
If the amplifier is mounted under a seat, be sure that there is adequate space  
around the amplifier once installed, 1” (25mm) recommended minimum. Do not  
allow seat padding or other obstructive material to press down on the amplifier.  
When mounting in a trunk, choose a location that will be protected from sliding  
cargo or other materials. Mount the amplifier to solid surfaces only. Do not  
mount to plastic trim panels. Do not mount the amplifier with Velcro, double-stick  
tape, or by wedging into position. Amplifier should be mounted using the screw  
mounts in the endpanels and with the provided mounting screws.  
Cooling  
Position the amplifier so that there is adequate space around the amplifier once  
installed, 1” (25mm) recommended minimum.  
4
Installation - Wiring  
Amplifier Fuses  
Although the amplifier has an internal fuse (s), additional fuse protection  
should be installed as close as possible to the battery on the positive (+) power  
wire going to the amplifier. An inline fuse should be installed at no more than  
18" (46cm) on the positive (+) power wire. The rating of the inline fuse should  
equal the value of the internal fuse of the amplifier if only the single amplifier is  
connected to this wire. If other devices are connected to this wire, the fuse  
value should be of sufficient capacity to handle the demand.  
Wire Gauge  
The amplifier accepts up to 8-gauge stripped wire at the DC power and ground  
input terminals, and 8-gauge is recommended as a minimum. Wire runs should  
be kept to the minimum practical length.  
Power 12v and Ground (GND) Connection  
Strip approximately 5/8” (16mm) of insulation. The positive (+) power wire is  
installed into the amplifier terminal marked “12v”. The negative (–) wire is  
installed into the terminal marked “GND”. The ground wire should be as short  
as possible and connected directly to the chassis of the vehicle. Make sure that  
the chassis connection point is free of rust, grease, dirt, paint, and other  
materials that may insulate the ground wire from making proper connection.  
Tighten the 12v and GND terminals with the supplied 3mm hex wrench to  
secure the wire into the terminals. If the power wire must be routed through a  
drilled or existing hole, use a nylon panel grommet to prevent the insulation  
from fraying. Failure to do so could lead to an electrical short if the wire  
insulation is worn through and the power wire is shorted to ground.  
Remote Input Connection  
Connect the REMOTE trigger lead from the head unit to the amplifier using the  
3mm hex wrench to tighten the connector on the power block of the amplifier.  
(refer to the diagram on page 3).  
Speaker Output Connection  
Prepare each wire by stripping approximately 8” (16mm) of insulation. The pos-  
5
itive (+) speaker wires are installed into the amplifier terminals marked “SPEAK-  
ER OUTPUT” / “+” (refer to the diagram on page 3). The negative (–) speaker  
wires are installed into the amplifier terminals marked “SPEAKER OUTPUT” / “-  
”. Tighten the “SPEAKER OUTPUT”, “+”, and “-” terminals with the supplied  
3mm hex wrench (2mm on GTA-504) to secure the wires into the terminals. If  
the speaker wires must be routed through a drilled or existing hole, use a nylon  
panel grommet to prevent fraying the wire insulation. Failure to do so could  
lead to an electrical short if the wire insulation is worn through and the speaker  
wires are shorted to ground.  
Note: Speaker outputs are marked “Front Output” and “Rear Output” on the  
GTA-504.  
Mono Subwoofer Operation  
When the amplifier is configured for mono operation, use the speaker output  
terminals marked for mono use (refer to the diagram on page 3).  
WARNING! Subwoofer impedance must not fall below 4 ohms when in  
MONO mode.  
5
Tuning The Amplifier - Front or Rear Speakers  
1) Music  
The material chosen for head unit/amplifier system setup must be both clear in  
recording quality and dynamic in amplitude. Many audiophile “test” discs have  
musical tracks with both of these characteristics and should be used.  
2) Input Sensitivity Control (Gain)  
Turn control all the way counterclockwise (minimum position). In this position, the  
amplifier will be less sensitive to the input signal from the head unit (refer to the  
diagram on page 3).  
3) Crossover Control  
Crossovers should be turned “OFF” during this phase of setup . Move the X-OVER  
switch to the “OFF” position (refer to the diagram on page 3), with these settings,  
full-range signal is sent to the speaker outputs. If over-excursion is detected from  
speakers, move the switch to “HP” and slowly rotate clockwise until over-excursion  
is eliminated.  
4) Head Unit  
The head unit should have all controls such as bass, treble, balance, and fader set to  
the flat or centered position. The volume control should be at the minimum setting.  
If the head unit has any equalization or bass management features such as boost,  
they should be defeated at this time. Turn head unit on, and verify that the BLUE  
status LED is illuminated on the amplifier.  
5) Volume  
With the chosen musical track playing, turn the head unit volume control up until the  
maximum level of undistorted signal is heard from the speakers. (For most head  
units, this will be near the end of the volume control range.)  
Configuration and Co  
GTA 2-Channel Amplifier Powering a Pair  
6
Tuning The Amplifier - Front or Rear Speakers  
WARNING! A distorted signal from the head unit sent to the amplifier can cause  
loudspeaker failure at higher listening levels.  
6) Input Sensitivity Control (Gain)  
Slowly rotate the control clockwise (refer to the diagram on page 3) until  
maximum undistorted playing level is heard from the speakers. Listen closely for  
bottoming from the speakers. If detected, rotate the input sensitivity control  
counterclockwise until it is eliminated.  
7) Crossover Controls  
To achieve higher undistorted playing levels from the main speakers, the Highpass  
crossover must be engaged. Rotate the crossover control fully clockwise (refer to  
the diagram on page 3). The highpass crossover point is now set at 200Hz. Q-Tune  
should be set to off.  
Slowly rotate the input sensitivity control clockwise until maximum undistorted  
playing level is heard from the speakers. Listen closely for bottoming from the  
speakers. If detected, rotate the input sensitivity control counterclockwise until it is  
eliminated. Slowly rotate the highpass crossover control counterclockwise while  
listening for bottoming. You are lowering the crossover point, which means that  
more bass signal is being sent to the speakers. If bottoming is detected, rotate the  
input sensitivity control counterclockwise until it is eliminated and/or rotate the  
Highpass crossover control clockwise to raise the crossover point.  
8) Q-Tune Control  
Q-Tune allows for +6dB boost of bass information centered at 45Hz and is not  
typically needed for full range speaker applications.  
fuse  
onnection Diagram:  
r of Full Range Speakers (80Hz Highpass)  
7
Tuning The Amplifier - Subwoofer(s)  
1) Head Unit  
The head unit should have all controls such as bass, treble, balance, and fader  
set to the flat or centered position. The volume control should be at the  
minimum setting. If the head unit has any equalization or bass management  
features such as boost, they should be deactivated at this time. Turn head unit  
on, and verify that the Blue status LED (logo) is illuminated on the amplifier.  
2) Volume  
With the chosen musical track playing, turn the head unit volume control up  
until the maximum level of undistorted signal is heard from the speakers. For  
most head units, this will be at the end of the volume control range.  
WARNING! A distorted signal from the head unit sent to the amplifier can  
cause speaker failure at higher listening levels.  
3) Input Sensitivity Control (Gain)  
Turn control (refer to the diagram on page 3) all the way counterclockwise  
(minimum position). In this position, the amplifier will be less sensitive to the  
input signal from the head unit. Slowly rotate this control clockwise until  
maximum undistorted playing level is heard from the subwoofer(s). Listen  
closely for faults such as bottoming from the subwoofer(s). If fault is detected,  
rotate input sensitivity control counterclockwise until fault is eliminated. At this  
point, the maximum undistorted subwoofer playing level has been defined.  
Configuration and C  
GTA 2-Channel Amplifier Poweri  
8
Tuning The Amplifier - Subwoofer(s)  
4) Crossover Control  
Move the selector switch to “LP” (refer to the diagram on page 3). In this  
setting, lowpass signal is sent to the speaker outputs. Experiment with the  
crossover point settings while the subwoofer is active. A higher setting will  
increase the perceived output, and a lower setting will make the bass  
response more omnidirectional.  
5) Q-Tune Control  
Once the crossover point has been determined, you may choose to use Q-Tune to  
increase the bass information. Q-Tune will offer a +6dB bass boost centered at 45Hz  
which can be beneficial if more low bass output is desired. To engage Q-Tune move  
the selector switch to the “ON” position (refer to the diagram on page 3).  
6) GTA-RSL Control  
The remote level control (GTA-RSL) gives you independent level adjustment of the  
subwoofer’s output level beyond the standard system volume control. Please refer  
to the RSL’s manual for installation instruction. The GTA-RSL is available separately,  
please consult your authorized Boston Acoustics dealer.  
fuse  
Connection Diagram:  
ing a Subwoofer (80Hz Lowpass)  
9
Tuning The Amplifier - Front Speakers and Subwoofer(s)  
1) Head Unit  
The head unit should have all controls such as bass, treble, balance, and fader  
set to the flat or centered position. The volume control should be at the  
minimum setting. If the head unit has any equalization or bass management  
features such as boost, they should be deactivated at this time. Turn head unit  
on, and verify that the BLUE status LED is illuminated on the amplifier.  
2) Volume  
With the chosen musical track playing, turn the head unit volume control up  
until the maximum level of undistorted signal is heard from the speakers. For  
most head units, this will be at the end of the volume control range.  
WARNING! A distorted signal from the head unit sent to the amplifier can cause  
speaker failure at higher listening levels.  
3) Input Sensitivity Control (Gain)  
Turn control (refer to the diagram on page 3) all the way counterclockwise  
(minimum position). In this position, the amplifier will be less sensitive to the  
input signal from the head unit. Slowly rotate this control clockwise until  
maximum undistorted playing level is heard from the subwoofer(s). Listen  
closely for faults such as bottoming from the subwoofer(s). If fault is detected,  
rotate input sensitivity control counterclockwise until fault is eliminated. At this  
point, the maximum undistorted subwoofer playing level has been defined.  
4) Front Crossover Control  
To achieve higher undistorted playing levels from the main speakers, the highpass  
crossover must be engaged. Rotate the crossover control fully clockwise (refer to  
the diagram on page 3). The highpass crossover point is now set at 200Hz. Q-Tune  
should be set to off.  
Configuration and C  
GTA-504 Amplifier Powering Both  
10  
80Hz Highpass Front, 65Hz L  
Tuning The Amplifier - Front Speakers and Subwoofer(s)  
4) Front Crossover Control Cont.  
Slowly rotate the input sensitivity control clockwise until maximum undistorted  
playing level is heard from the speakers. Listen closely for bottoming from the  
speakers. If detected, rotate the input sensitivity control counterclockwise until it is  
eliminated. Slowly rotate the highpass crossover control counterclockwise while  
listening for bottoming. You are lowering the crossover point, which means that  
more bass signal is being sent to the speakers. If bottoming is detected, rotate the  
input sensitivity control counterclockwise until it is eliminated and/or rotate the  
Highpass crossover control clockwise to raise the crossover point.  
5) Rear Crossover Control  
Move the selector switch to “LP” (refer to the diagram on page 3). In this  
setting, lowpass signal is sent to the speaker outputs. Experiment with the  
crossover point settings while the subwoofer is active. A higher setting will  
increase the perceived output, and a lower setting will make the bass  
response more omnidirectional.  
6) Q-Tune Control  
Once the crossover point has been determined, you may choose to use Q-Tune to  
increase the bass information. Q-Tune will offer a +6dB bass boost centered at 45Hz  
which can be beneficial if more low bass output is desired. To engage Q-Tune move  
the selector switch to the “ON” position (refer to the diagram on page 3).  
7) Optional GTA-RSL Control  
The optional remote level control (GTA-RSL) gives you independent level adjustment  
of the subwoofer’s output level beyond the standard system volume control. Please  
refer to the RSL’s manual for installation instruction. The GTA-RSL is available sepa-  
rately, please consult your authorized Boston Acoustics dealer.  
Note; If using the GTA-504 to run front and rear speakers, set rear X-over to HP and  
follow set up/tuning instructions for the front channels for rear.  
fuse  
Connection Diagram:  
h Front Speakers and a Subwoofer  
11  
Lowpass Rear w/ Q-Tune On  
Amplifier Troubleshooting Guide  
Status LEDs on Amplifier not Lit—Head Unit (Source) Turned “ON”  
Verify  
Remote turn-on wire from source to amplifier has proper voltage  
Power (B+) connections at amplifier, terminal blocks, and battery are secure  
Ground (GND) connections at amplifier and vehicle chassis are secure  
Battery B+ fuse and amplifier fuse are OK  
B+ at battery and B+ at amplifier have proper voltage  
Status LEDs Lit, no Output from Speakers—Speakers in Normal Operating Condition  
Verify  
High-level cables from speaker(s) to amplifier are securely connected  
RCA or Speaker Level Input from amplifier to source are securely connected  
Sensitivity adjustment on amplifier is correctly adjusted  
Engine Noise from Speaker(s)  
Turn source “OFF” and disconnect RCA cables at amplifier  
If noise stops, check equipment and cables leading to amplifier  
RCA cables are of good quality with no breakage to internal shields  
RCA cables from source to amplifier are not run alongside power  
Verify  
Amplifier Output Distorted—Music not Recorded with Intentional Distortion  
Verify  
Source output to amplifier is not distorted  
Amplifier input sensitivity is correctly adjusted  
Amplifier Shutting Down, RED LED Lit—Amplifier in Thermal Protection Mode  
Verify  
Amplifier is mounted with adequate space around heatsink  
Amplifier is not mounted under carpet  
Speakers meet correct impedance for application (mono or stereo hookup)  
Amplifier not Turning “ON”, RED LED Lit—Amplifier not Connected to a Shorted Speaker  
Verify  
Speaker crossover is not defective  
High-level cables from speaker to amplifier are not shorted  
Amplifier not Turning “ON”, RED LED Lit—Speakers, Crossovers, and Cable OK  
Internal fuse needs to be replaced  
Verify  
Replace fuse with fuse of same value  
Amplifier not Turning “ON”, RED LED Lit—Speakers, Crossovers, and Cable OK  
Amplifier requires service  
If Service Seems Necessary:  
First, contact the dealer from whom you purchased the product, or contact us via e-mail at:  
USA and Canada: [email protected]  
Asia/Pacific countries: [email protected]  
We will promptly advise you of what action to take.  
Boston Acoustics, Inc. 300 Jubilee Drive, Peabody, MA 01960 USA  
T: 978.538.5000 F: 978.538.5100 W: bostonacoustics.com/car  
Boston, B/A ellipse symbol, Boston Acoustics, and the Boston Acoustics logo are registered trademarks and Q-Tune is a trademark of Boston Acoustics, Inc.  
Specifications are subject to change without notice. © 2009 Boston Acoustics, Inc. All rights reserved. Covered by patents issued and/or pending. 142-003796-0  

Bassworx BSX62 1 User Manual
BenQ LCD Monitor XL2410T User Manual
Blaupunkt Orlando CD70 User Manual
Brunton NOMAD V2 PRO User Manual
Casio SF 4900ER User Manual
Channel Plus H721 User Manual
Clarion DXZ668RMP User Manual
Directed Electronics 250d User Manual
JBL GTO507C User Manual
Jensen MP6610 User Manual