Installing an Amplifier

In This Chapter :

•     Picking the best spot to mount an amplifier
•     Wiring an amplifier
•     Putting safety first with fusing and a good ground

    You can think of an amplifier as the heart of a car audio system. All of the wires that tie together a system lead to and from the power amplifiers. And just like your ticker, you have to take good care of your amp — or, in the case of your amp, ensure that it’s installed correctly — to keep it pumping out juice. When something goes wrong with your heart, it affects not only your circulatory system, but your entire body, too. Likewise, if something goes wrong with your amplifier, particularly if it’s not installed correctly, it can have dire consequences for not only the amp and other car audio components, but also your car.

In this chapter, I cover the most important aspects of installing an amplifier and whether you should do the installation yourself or seek professional help from an installer. I also direct you to Internet resources that can help you if you do decide to go the DIY route. 1 also explain how an amplifier affects a vehicle’s charging system so that both your car and your amplifiers don’t run out of juice

see more Keeping It Quiet for Reproducing Great Audio

In addition, I detail the best places to mount an amplifier, where not to mount one, and why some locations are better than others. I also discuss the role wiring plays in installing an amplifier and the importance of proper fusing. Finally, you find out why keeping an amplifier grounded is so important.

Gathering the Facts Before you Amp Up

Amplifiers are the most daunting car audio components to install correctly. First, you have to decide where to mount your amps. Some components have really obvious locations. For example, head units have a stock slot in the dash that they fit into, and speakers typically mount in predetermined factory provisions. Although many stock premium car audio systems come with separate amplifiers, they are usually small, nondescript silver boxes designed to fit inconspicuously in a vehicle.

But you’ll probably want show your amps off, and they’ll need to be some¬what accessible in case you need to make adjustments to the amps’ controls. There are also other, more important considerations when you’re deciding where to place an amplifier in a vehicle. Proper ventilation and routing of wires are crucial factors to consider.

Amplifiers are the most complex car audio components to successfully and safely integrate into a vehicle. While most speaker installations are pretty straightforward and many head units can be installed by do-it-yourselfers, amplifiers present a unique set of install challenges, and the job may be best left to a professional.

If you botch a speaker or head unit installation, you may damage those components or an adjacent part of your car. But with a faulty amp install, you can end up shorting out your electrical system or even setting your car on fire.

If you’re determined to take on the amp installation challenge, make sure you have two things: lots of patience and a good grasp of the way your vehicle’s charging system works. I can explain a bit about the charging system, but you’re on your own with the patience.

also see Protecting Your System and Yourself : Securing and Insuring Your System

Here are the things you need to consider before undertaking the installation of an amplifier:

The complexity of the system: If you are comfortable working on cars and you’re installing, say, only one simple two-channel amplifier; the task may not prove too difficult. But if you plan to have multiple amplifiers running a barrage of speakers, you may be better off paying a professional to do the job.

The complexity of the can If you’re installing an amp or two in, say, a 1984 VW Rabbit, the installation should be pretty straightforward. But if you plan to pimp out your new S Class Mercedes with the mother of all car audio systems, complete with a rack of amps, you’ll need to tread i very lightly and know exactly what you’re doing.

Knowing watts what: Before installing an amplifier, you should have a good grasp of how a car’s charging system works. If you don’t know a grommet from a ground cable, for example, it’s probably best to find a good professional car audio installer or at least an experienced DIYer. But if you comprehend the complexities of your car’s electrical system, know the difference between voltage and resistance, and can handle running wires and taking your car apart and putting it back together again, you can consider going the DIY route.

Just remember that many car audio amplifier manufacturers offer a longer warranty — two to three years instead of one — if their products are installed by an authorized dealer.

Getting Comfortable with your Car’s Charging System

To your car’s battery, a car audio amplifier is just another current-consuming device, just like your windshield wipers or power-window motors. Auto manufacturers design a vehicle’s electrical system to handle the total load that all of the car’s electrical device can place on it, and then some.

Not only do they engineer in a margin of error for those days when you may be, say, running your air conditioner at full blast, operating the windshield wipers on high, shining the high beams, and blowing your horn all at the same time, but they also know people will likely add aftermarket accessories, such as car audio systems.

But at what point does your car’s electrical system say enough is enough? That depends on how much you demand of it. Fortunately, music is transient in nature, meaning there are lulls that don’t require a lot of extra power and there are crescendos, as well as peaks — or in the car audio sense, ground- pounding bass notes — that do. It’s during these transient peaks that a car’s electrical system can be taxed to the max.

 

The amount of current drawn from the electrical system depends on the amplifier. But say you have a typical stereo amp that’s rated at 100 watts x 2 channels. Such an amp would draw between 15 and 30 amperes of peak current. No big problem there, but say you install four of these bad boys. Then you’re asking your charging system to supply on average between 60 and 120 amperes of peak current. That’s when things start to get tricky.

As long as you’re listening to talk radio at moderate volume, it may not be a problem. But if you’re bumping the latest bass-heavy CD, you’re amplifiers may not receive enough current and begin to clip the audio signal. This causes distortion that can blow the speakers, in some cases, you even find your headlights dimming to the beat. Although you may think that this is kind of cool, your car won’t, and your alternator may wear out much faster under these conditions.