Installing Or Replacing A Car Stereo Amplifier
(also known as a "power amp")
(General considerations applying to most installations)

MOST IMPORTANT!!
Read the instructions that came with your amplifier!!!!.
1) Select a location for the amplifier that has good air circulation, such as in the trunk,or under a seat.

2) Use larger diameter RCA cables to connect the low-level output of the radio to the low-level input of the amplifier.

3) If the radio does not have a low-level output, you will need to use the high level, or speaker output. Generally, this is less desirable because of the noticeable increase in distortion and noise in such an arrangement. If your amp is for bass only, this may be a less significant problem.

4) Connect the power lead for the antenna from the back of the radio and connect to the amplifier turn-on input. Now turn on the radio. 12 volts should go to the lead and turn on the amplifier when connected to the main power leads.

Make certain that the power antenna lead stays on while the stereo is on. On many new radios, power may be switched off from the lead when a CD or tape is played, so the power antenna will come down. If this is the case with your radio, it will have a separate lead coming out for the amp turn-on. Test the lead with a VOM, or test light. When the radio is on, in any function, 12 volts should be present at the amp turn on lead until the radio power is turned off.

5) Connect the main power (+) for the amplifier directly to the battery. Use a fuse on the line at the battery and amplifier. Check your owner's manual for the proper rating for the fuse. Fuse your amplifier(s) as close to the battery as possible. Current ratings (amps) usually doubles w/ each amplifier added to the circuit. For example, if you have one amplifier, use a 30amp fuse. Two amplifiers? Use a 60amp fuse.

Ensure that power cables do not run next to RCA signal cables. If the cables are too close, engine noise, which sounds like a high-pitched whine, can get into the system. In addition to having your RCA cables mounted away from power cables, make them as short as possible, as signal strength is lost over distance.

Connect the power cables before the RCA cables to prevent damage. If RCA cables are connected first, the amp may try to ground from these cables, possibly causing damage to other components in the system.

6) Check the owner's manual for the correct gauge (size) of the power and ground cables.

7) Use the same gauge cable for the amplifier ground (-) as you do for the amplifier battery (+). The ground cable should be kept as short as possible. Find a good ground. Clean the area you select for ground and bolt the wire to that location. Many of today's cars have fiberglass bodies. Fiberglass does not make a good ground conductor. Ground your amp to a solid piece of metal frame.

8) Use 16-12 gauge speaker wire and connect the wire from the speakers to the amplifier. Make sure that the wire connected to the positive terminal of the speaker is connected to the positive terminal on the amplifier and the wire connected to the negative terminal of the speaker is connected to the negative on the amplifier. If using multiple speakers, avoid overloading from improper impedance matching.

9) An important indicator of inadequate power for your system is dimming lights whenever heavy bass is output. Two possible solutions are a heavier alternator, and/or the installation of a large power storage capacitor. This last item will store large amounts of power until called for by the amplifier. It is generally less expensive than a replacement alternator.