Install your woofer in your door or in your kickpanel (shown here in a QLogic kickpanel pod).

Woofer placement

The dash, doors, and kick panels serve as the most common homes for woofers. In many cases, you'll be able to mount the woofers in the factory speaker locations with little to no adjustments — the "easy fit" option. At most, you'll have to drill extra screw holes, cut a small area of metal or pressboard, or file the door panel. "Modify fit" speakers require a greater degree of cutting and drilling. Before you begin, you must be sure that modifications will not interfere with any car mechanisms, and that the speakers will fit securely. Though you can relocate any speaker, whether it be "easy" or "modify" fit, be aware that the process can be complicated and time-consuming, especially for first-time installers.

Place your tweeters in the door, the sail panel, even the dash (not pictured).

Tweeter placement

Many people choose to install their tweeters on the doors, the sail or kick panels, or the dash. Tweeter installations require some panel modifications, as very few vehicles come with factory tweeter mounts. The degree of modification depends on the mounting method. Just as it sounds, surface-mounting places the tweeter on top of a surface, with little to no modifications necessary. Of course, this method will leave you with a more noticeable installation. A flush-mount, on the other hand, gives a smooth, customized look. It requires cutting a hole into the door panel for the tweeter so it sits level with the interior panel. Whichever method you choose, most manufacturers recommend that you mount your tweeters within 12" of the woofers. Otherwise, the high and low frequencies may reach your ears at different times, resulting in a sonic wave cancellation or "phase interference."

Crossover placement is just as important as speaker placement.

Crossover placement

Though crossovers usually require little in the way of car adaptation, finding the right place to house them can be tricky. The crossovers need to be kept in a place where they won't interfere with any of the car's moving parts, and where they won't get wet or vibrate. While some people choose to permanently mount them under the seats or on display, it's often just as easy to find a convenient spot for them behind the mounting panel near the speakers. The closer the crossover is to the speakers, the better, as the proximity will cut down on noise. The doors and behind the kick panels serve as two good options for housing crossovers.

Add-ons

The following installation instructions will also apply if you are adding a set of speakers (midranges, tweeters) to your current aftermarket system.