One of the joys of the road, beyond the travel itself, is the ability to put the journey to music. We often pay more attention to music in our cars than anywhere else, and yet we often wind up listening to that music on the worst stereo in our possession.

A modest investment in good sound will go far towards increasing your driving pleasure, reducing stress on the road, and in general making the journey more pleasant. Music, to paraphrase a famous saying, soothes the savage driver. Properly selected and installed, a good car stereo system will improve the resale value of the car as well. (grimly fiendish points out that this is not always the case, but I have found out from personal experience that it at the very least helps you keep your asking price firm.) The advantages of good car sound are more than worth the initial cost.

Start from scratch, or add-on?

The first basic question to ask when planning your car stereo is whether to add-on to the existing factory stereo, or take it out and start from scratch. There are advantages to both approaches. Adding-on can be less expensive than a new stereo. The question here is what do you want to accomplish. Do you want a clearer, tighter, sound? That can often be achieved simply by replacing the factory speakers with aftermarket speakers. The difference here is that factory speakers tend to be one-way designs, with no midrange or tweeter. A new set of speakers with a two- or three-way design will make your music sound much better. Do you want it to sound louder, as well? There are amplifiers that will attach directly to your factory radio’s speaker wire outputs, to give you the power you need. Be careful though, because if the amplifier is not designed to be hooked up that way, you will destroy it.

Do you just want CD capability? There are add-on CD changers that fit in the trunk that will attach to any radio through the antenna line. The sound quality is better than tape, but not as good as a direct CD connection. For single CD’s, the best way to go is still the old tried-and-true cassette adapter.

Sometimes because of the type of car involved, adding on may be the best or only choice. For example, many new cars have factory custom-fit radios. These cars, like the Ford Taurus, have dashboard holes that just do not fit an aftermarket radio. There are many kinds of dash adapters for these kinds of car to put in a standard-shape deck, but the finished look is nowhere near the same, unless you spend on some custom refitting. So you could say that the choice exists for every car, but then the variables involved definitely steer people into one direction or the other.

A system walk-through

Let’s say you have decided to replace everything, or your car never had anything to begin with. Let’s walk though a full-blown system, and see what goes into it. Any level past the first step (deck & speakers) is icing on the cake, but for those who want to go all the way, the result is worth it.

Let’s start with the radio. The choice in decks has expanded, now that we can choose between CD, MiniDisk, and Cassette. You can even get an in-dash CD changer with a three or four CD changer. The quality of the radio's reception is also important. Fancy features like RDS may not be necessary, but good tuner will make your listening experience better. Other radio features like auto-search pull in the strongest stations and put them in your radio’s memory, and Diversity tuning uses two antennas to improve reception and reduce multipath interference.

Once you have decided on a head unit, you need to think about speakers. Look in your car and find all of the factory speaker spots. The easiest path here is to replace the factory speakers with high-end replacements, as in the simple upgrade mentioned previously. However, many times you will be forced to install extra mid- or mid-bass-range speakers in the doors or back deck to complement the small factory speaker openings, which are usually only large enough to hold tweeters or small midranges. With the main speakers in place, it is often necessary to add a sub-woofer in the trunk to provide the lower frequencies. These speakers also come in a separate enclosure, or as separates. Since bass in omnidirectional (the human ear can’t tell easily where it is coming from) it can be mounted almost anywhere, the default location being the trunk. Many woofer boxes are self-powered, which allows them to be hooked up to most head units, or unpowered units can be driven by an external amplifier.

With speakers dealt with, there remains the question of how to drive them. If you only use four basic speakers, you can usually drive them with the amplifier in the head unit. The power output there is about 10-20 watts continuous (expressed as RMS power.) Many decks will say on their packages that they can put out upwards of 40-45 watts, but these are peak outputs, and are therefore misleading. A good amplifier will make the most of the potential sound your speakers are capable of putting out. As far as matching amp to speakers, it’s easy. Just match the RMS output of the amp in each channel to the RMS power input of the speakers. Speakers also often list peak power, so look on the box for the RMS wattage. If none is given, a rule of thumb is to divide the peak reading in half. One thing to remember is that what the speaker claims as its power output is what it can handle, not the power that comes out of it. You could have speakers claiming 500 watts, and if they are hooked up to a 50-watt amp, they will put out 50 watts.

Take the time to do it right

It has been said that excellence is in the details. The same goes for car stereo. Now that you have all of the gear you wanted, don’t just throw it into the car. If you are going to do it yourself, it is worth the investment to get the right tools to install it properly. The first thing to concern yourself with is the dashboard. Do you have the right frame to make the radio fit properly? Do you have the proper wire harness adapter? When you make the connection, use wire ties to keep the wires from tangling, and if you have to join any wires, use a soldering iron if at all possible. Please make sure that if you are testing the wiring in a car with air bags, use a diode-protected probe or multimeter. If you use a regular test light, you can accidentally trigger the air bag if you probe the wrong wire. When in doubt, run all new power and speaker wiring, or have a pro install it. It may cost a little more, but will be well worth it in the long run.

Don’t forget to use decent cables. The more power you are pulling for the amp, the thicker a power cable you need (ALWAYS PUT A FUSE WHERE THE CABLE CONNECTS TO THE BATTERY). RCA cables for the car should also be double-shielded, to minimize noise. Also, route power cables separately from signal cables, also to minimize signal noise. If you hear some noise, check your ground (it should be direct to the sheet metal) and if necessary, put a filter on each power line. A whine the changes pitch with the engine speed is coming from your alternator. You may need to get a noise-suppression kit for your engine that handles alternator and spark-plug interference.

If you have a rattle in your trunk or doors, use some sound-deadening material. This will be especially evident on those low bass notes, which usually cause the license plate to buzz against the trunk mount (if that is the only problem, a piece of kitchen sponge will fix it.) I always laugh whenever I hear a car go "buzzing" past.

The key is to take the entire job, from selection to installation, step by step. The efforts you put into your car stereo system now will pay off over the long run in increased listening pleasure and trouble-free ownership.

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