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.