Trunk Mount Amplifier (120-1975/A) Preparation Faxback Doc. # 17492 CHOOSING A MOUNTING LOCATION Choose a mounting location that: Does not interfere with the vehicle's operation. Lets you drill mounting holes without damaging other vehicle components. Allows enough space around the cooling fins for proper airflow and cooling. Is not near a heater vent. WARNING: The amplifier gets very hot while in use. Do not touch the amplifier or place flammable objects near it while it is on. BEFORE YOU MOUNT THE AMPLIFIER IMPORTANT: Please note that the installation might require cutting or modifying your vehicle. To properly install your amplifier, you should be able to answer all of these questions about your vehicle's electrical and existing sound systems. Does my vehicle have a 12-volt negative ground electrical system? Which of the amplifier's wires is the power wire? Which terminal on my vehicle's fuse box is for accessories? How do I connect a wire to the fuse box? Be sure your front speakers can handle 25 watts of power and your rear speakers 50 watts. Each speaker must have an impedance of at least 4 ohms. Your local Radio Shack store carries a full line of speakers. Before you permanently mount your amplifier, temporarily connect the amplifier, stereo, and speakers and test the stereo system. Do not mount the amplifier until you are sure all connections are correct. MAKING THE CONNECTIONS To prevent damage to your sound system while making the connections, disconnect your vehicle battery's negative (-) terminal. NOTE: After you make all the connections and reconnect the battery terminal, you must reset the clock, the radio's digital tuner memories, and other timer/memory devices. Connecting Power Follow these steps to connect power to the amplifier. 1. Connect the supplied black (ground) wire's open end to the amplifier's GND terminal. Then connect the other end to a nearby part of the vehicle's metal frame that is not insulated from the frame by a plastic part. 2. Connect the supplied red (power) wire's open end to the amplifier's +12V terminal. Then connect the other end directly to the vehicle battery's +12-volt power source. Be certain to use a fused power source, or to place a 20 amp "Fast-Blow" fuse at the power source (battery terminal, etc...). Connecting the Remote Power Lead The remote power lead turns the amplifier on and off. 1. If your stereo system has a remote power output lead, connect the supplied dark blue/white wire's male quick-disconnect plug to your stereo's remote power output lead. This lead turns the amplifier on and off when you turn your stereo on and off. If your stereo system does not have a remote power output lead, connect the supplied dark blue/white wire's male quick-disconnect plug to a point in your vehicle's ignition switch that provides 12-volt battery power when the ignition is set to ON or ACC. This lead turns the amplifier on and off when you turn your ignition switch on (or to ACC) and off. 2. Connect the dark/blue/white wire's other end to the amplifier's REM (Remote) terminal. Connecting the Amplifier Inputs Place the amplifier as close as possible to the selected mounting location. Connect your vehicle stereo's output jacks to the amplifier's LOW INPUT or HIGH INPUT jacks as follows: If your vehicle stereo system has low-level phono outputs, you can connect them to the amplifier's LOW INPUT phono jacks. To make the best connections, you need shielded audio cables, such as Cat. No. 42-2368 (not supplied). You might also need shielded Y-adapter cables, such as Cat. No. 42-2435 (not supplied). 1. Connect one end of an audio cable to each of your stereo's phono output terminals using the following guidelines: If your stereo has four phono outputs (front-left, front-right, rear- left, and rear-right), use four cables and connect one end of each cable to each of the stereo's four output jacks. If your stereo has two phono outputs (left and right), use two cables and connect one end of each cable to each of the two output jacks. Then connect the phono jack ends of two Y-adapter cables to the two shielded audio cables. 2. Connect the other ends of the audio cables to the amplifier's LOW INPUT terminals using the following guidelines: If you used four shielded audio cables in Step 1, connect the front- left, front-right, rear-left, and rear-right cables to the corresponding LOW INPUT FRONT-LEFT, FRONT-RIGHT, REAR-LEFT, and REAR-RIGHT phono jacks on the amplifier. If you used two shielded audio cables, each with a Y-adapter cable in Step 1, connect the left Y-adapter cables' two phono plugs to the LOW INPUT LEFT-FRONT and LEFT-REAR terminals on the amplifier. Then connect the ends of the two right Y-adapter cables to the LOW INPUT RIGHT-FRONT and RIGHT-REAR terminals on the amplifier. NOTE: For a cleaner, less noisy signal transfer between your stereo system and the amplifier, the amplifier's LOW INPUT phono jacks are gold-plated. If your stereo system has only speaker outputs, you can connect them to the amplifier's HIGH INPUT socket. Refer to the following illustrations in Faxback Doc. # 17260. 1. If your stereo has four speaker outputs: a. Floating Ground Connection b. Common Ground Connection 2. If your stereo has two speaker outputs: c. Floating Ground Connection d. Common Ground Connection Connecting the Amplifier Outputs With your speakers placed in the approximate locations, measure the distance from each speaker to the amplifier. We recommend you use 16- or 18-gauge color-coded or marked wires to help you correctly connect the speakers to your sound system. Color-coded wires have a stripe running down one of the conductors and marked wires have ridges along one of the conductors. Your local Radio Shack store has a wide selection of speaker wire. CAUTIONS: To prevent the speakers from overloading the amplifier and causing the amplifier to automatically shut down, do not connect speakers with an impedance of less than 4 Ohms. Do not connect any of the speaker wires to chassis ground. Use all the wires to connect the speakers to your amplifier. NOTE: For maximum bass response and the best overall performance, keep your speakers properly phased (connect + to + and - to - ). 1. Separate the speaker wire's two conductors at both ends for a length of about 4 inches. 2. Strip the insulation from the ends of each conductor to expose 1/4 inch of metal wire. 3. Connect one end of a marked speaker wire to the front-left speaker's positive (+) terminal. 4. Connect one end of an unmarked speaker wire to the front-left speaker's negative (-) terminal. 5. Connect the other end of the marked wire to the amplifier's positive (+) FL (front-left) terminal. 6. Connect the other end of the unmarked wire to the amplifier's negative (-) FL (front-left) terminal. 7. Repeat Steps 1-6 to connect the front-right speaker to the amplifier. 8. Repeat Steps 1-7 to connect the rear speakers to the amplifier's RR (Rear Right) and RL (Rear Left) speaker terminals. Testing the Connections Reconnect the vehicle's negative (-) battery terminal, then turn on your vehicle's ignition and verify that everything works properly. If the stereo system does not work properly, IMMEDIATELY TURN OFF YOUR VEHICLE'S IGNITION. Then disconnect your vehicle's battery's negative (-) terminal, and recheck all the connections. If you verify that the stereo system works properly, mark the connections to insure easy identification of each wire, then follow the instructions under "Mounting the Amplifier." MOUNTING THE AMPLIFIER 1. Disconnect your vehicle battery's negative (-) terminal and the stereo system's wiring harnesses. 2. Using the mounting holes on the amplifier as a guide, mark the locations for the mounting holes. 3. Drill 9/64-inch (3.57 mm) holes in the marked locations, taking care not to damage anything behind the mounting surface. 4. Attach the amplifier to the mounting surface using the supplied sheet- metal screws and washers. 5. Reconnect your vehicle battery's negative (-) terminal. 6. Reconnect the stereo system's wiring harnesses. (CS/all-10/23/95)