Installing an amp means routing cables for both power and audio signal.

Installation issues

The installation of an amplifier using speaker-level inputs does not differ significantly from one with preamp outputs. Before you do anything, you'll want to disconnect the negative terminal from your battery to protect against a possible short circuit.

Working from your car's passenger compartment, you'll run the red power wire from your amp kit through your vehicle's firewall, route it to your battery, and connect it to the fuse holder. Mount the fuse holder, and secure the connections to the radio and the battery. This will help you get power. You'll also route your red (power) and blue (turn-on) wires under door panels (or under seats) to your amplifier.

In addition to power, you'll need an audio signal. For each speaker, or subwoofer, that you plan to drive with an amp, strip back a small part of your vehicle's color-coded left and right speaker wires, then splice in the wires that lead to your amplifier. (Solder or crimp, and secure the connection for optimum performance.)

If your amp is in your trunk, it's a relatively short path to rear deck speakers or a subwoofer. Driving front seat speakers will require you to run wiring under a door jamb or the floor carpeting to reach the speakers. Likewise, if your amp is under a front seat, the front speakers are more accessible than the rear ones.

Be sure to check out our articles on step-by-step amplifier installation instructions, amplifier installation tips and tricks, and our installation video — it's a great teaching tool whether you're installing your first amp, or your 100th.