Materials that improve speaker performance
Many factory speakers lack dedicated high frequency drivers ("tweeters"). With the tweeters in name-brand speakers, though, you'll enjoy superior high frequency sound. Cone tweeters are efficient and economical, while dome designs — the kind you'll find in home speakers — create a wider dispersion pattern for more accurate reproduction. Tweeters made of poly or silk will improve your treble output and sound smoother than paper tweeters.

Woofer cones made of polypropylene and similar materials deliver more consistent, reliable bass notes and withstand the demands of heat, cold, and moisture better than paper woofer cones.

Rubber surrounds are a solid choice for punchy bass and extended speaker life. They also are less prone to split or decay than paper or even foam surrounds.

The right Car Speakers for your system design
If you plan to drive your speakers with a low-powered factory receiver, you need highly-efficient speakers. Check out the speaker sensitivity to find the most efficient speakers for your vehicle. (For instance, a speaker rated 3 dB higher than another will require half as much power to produce the same output.)

You're not confined to speakers with high efficiency ratings, of course. Low efficiency speakers can sound great. Since high sensitivity speakers often achieve their ratings by boosting deeper bass notes, low efficiency speakers might be preferable for listeners who demand highly accurate reproduction.

Also, if you use your factory receiver, get speakers with a minimum RMS power rating of 2-5 watts. A low-powered receiver may not be able to drive less-efficient speakers properly, causing distortion. If you like your music loud, you'll want speakers that can handle a substantial amount of continuous power. When using an amplifier, make sure its RMS wattage is within your speakers' power range (preferably, the upper third of your speaker's recommended power range).
2-Way, 3-Way, and 4-way Car Speakers
Most speakers are 2-ways, or coaxials with a single tweeter mounted above the cone of its woofer.

If you like more detailed vocals and midrange frequencies, a 3-way (a triaxial) adds a midrange driver for improved clarity. A 4-way adds a supertweeter for even more detailed high frequencies. (Some 3-way speakers use a supertweeter instead of a midrange.)

Component Speakers
The separate woofers, tweeters, and crossovers in a component system give you better power handling and performance than most 2- or 3-way speakers. Also, you can improve the stereo imaging in your car depending on where you mount tweeter separates. Installing components usually requires some cutting of metal or other procedures that can be more time-consuming than simply replacing factory speakers with similarly-sized models.

Mounting applications
Be sure to check the speaker's mounting height (for a top-mount application) or tweeter protrusion (for bottom mounts) so that door panels and grilles fit in place after the installation.

Certain speakers do not come with replacement grilles, including most 3-1/2", 4"x6", and 5"x7"/6"x8" speakers. You can retain your factory grilles for these and other speakers as they should be suitable for installation.

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