The Basics: Car Speakers
Upgrading the speakers in your car is perhaps the easiest and most popular mobile entertainment improvement possible. Due to the popularity of this upgrade, you'll find more choices than any of the other categories. Just walk into any car audio specialist and you'll see the vast array of options. The speakers that come in most cars are usually not quite top of the line, although many automobile manufacturers have recognized the importance of good speaker design, so they are using some really good components as an incentive for the entire automobile purchase.
Subwoofers are the most immediately evident improvement one could make to an automobile's sound system. The speakers that most manufacturers install in their cars are too small to properly and accurately produce low bass frequencies. In this case, size does matter. Speaker size does dictate the volume and ranges of frequencies it will be able to produce. However, a driver that is too large might take too long to react to the demands of music--they don't have an accurate transient response.
Subwoofers are available in two forms--raw and enclosed. An enclosed subwoofer consists of a driver mounted in a box, or it can refer to a band-pass box. A raw subwoofer is just the driver--a speaker cone suspended in a "spider," the metal frame that holds the speaker. The motor consists of the voice-coil and magnet. Enclosed subwoofers are typically unpowered, so you'll need a channel of amplification. However, there are some enclosed systems that include an amplifier specifically designed for the subwoofer component, which takes a lot of guesswork out of the equation.
How to Shop
"Drop-ins" are designed to fit exactly in the cutout spaces used by the factory speakers. This eliminates the need to alter the interior of your car in any way (ideal for a leased vehicle) and installers can usually incorporate the existing speaker grilles for a truly stealthy look. This is probably the easiest option for do-it-yourselfers. Simply remove the speaker grille, unscrew and remove the original speaker, disconnect the speaker wires, and connect and attach the new speaker. If you're planning on a more intrusive upgrade, most cars have additional speaker cutouts (for upgraded factory systems) hidden in a variety of locations throughout the interior frame. Any good installer will know where they all are. Many audio manufacturers design speakers in a variety of shapes and sizes to fit a variety of factory cutouts. Some retailers have a detailed listing of what speakers can be placed in what cars using cutouts or to use as drop-ins.
Once you've determined where you want speakers, you'll need to determine what kind to get. Replacement speakers come in two basic designs: coaxial or component. A coaxial speaker has the tweeter suspended over the woofer. A typically more expensive component speaker system consists of a separate woofer and a tweeter that can be positioned for a more accurate high-end response and a wider stereo image. They usually come with the necessary crossover electronics. Although usually considered a separate upgrade, you can also add a subwoofer.
Depending on what other components you are using, you should look at the sensitivity rating of the speakers. This indicates how efficiently the speaker handles the power that is supplied by your amplifier or head unit. Also called an efficiency rating, the higher the number, the louder your speakers can play given the same amount of amplification.
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