How to Install an Amp Without RCA Jacks

By Joseph Eitel

Speaker level inputs on an amplifier

Installing an amplifier in your car's audio system can seem overwhelming, but installing one without RCA jacks can be downright intimidating.Older systems usually lack RCA jacks, but just because you have an older system does not mean you cannot add an amp for additional power to push your speakers or subwoofers. Before you begin the installation process, it's imperative that you make sure the amp you've chosen is capable of accepting speaker or line-level connections. You'll also want to confirm that the RMS power of the amp is less than or equal to the RMS power of your speakers. Once you've double-checked these things, you're ready to start.

How to Install an Amp without RCA Jacks

Determine an ideal location for your amp inside the cabin or trunk of your vehicle. You can mount it on the back of a seat, on the sidewall, on the back of your subwoofer box or on the floor of the trunk away from any loose items that may damage the amp by shifting when the car moves.

Disconnect the negative terminal of your car's battery for safety purposes.

Open the amp wiring kit, which contains all the wiring you'll need to hook-up your amp. You will need to connect the lengthy, red wire to the positive terminal of the battery. This red power wire should be thicker than your speaker wire--typically 8-gauge works fine.

Run the positive wire back towards the cabin of the car, avoiding sources of heat and areas that are likely to be splashed by water when driving in inclement weather.

Run the remaining cable through the fire wall, using a rubber grommet if it seems likely the insulated wiring may encounter sharp metal.

Run all of the cables below the carpeting to where your amp is located.

Hook up both the positive and negative cables to the amp and find a grounding point within range of the negative cable. You can connect the ground wire to any secure metal piece on the frame of the car that does not have paint on it. Often times, you can find a nut/bolt behind your trunk's carpeting that will work perfectly.

Run speaker wire from the outputs, located on the back of the head unit, to the amp, being sure the sound wires run on the opposite side of the car from the power wires. Otherwise you may hear static interference through your speakers.

Run speaker wire from the speaker outputs on the amp to each speaker or subwoofer you wish to be powered by the amp.

Connect the speakers to the speaker wires using electrical tape or wire nuts.