GTA High Performance Two and Four Channel Amplifiers
Specifications Introduction Thank you for choosing Boston Acoustics and congratulations, you’ve made the right choice. You’re now equipped for the open road. Your high performance GTA amplifiers are engineered to perform and built to last. These products represent the pinnacle of performance and innovation that Boston Acoustics is famous for. We hope you enjoy your amplifier and the road ahead.
Connections / Controls Connections and Controls GTA-502 2 1 3 4 5 6 5 6 7 9 10 8 11 GTA-802 3 4 2 1 7 9 8 10 11 GTA-504 u v w x y z { | } ~ 1 2 3 4 6 1 2 3 4 5 7 6 8 9 10 11 Speaker Level Input RCA Input (Left and Right) Gain (250mv to 5.
Installation - General 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.
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.
Tuning The Amplifier - Front and Rear Speakers 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).
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.
Tuning The Amplifier - Subwoofer(s) 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.
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.
Tuning The Amplifier - GTA-504 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.
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.
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 cable
