How to Build a Car Stereo System

Building a car stereo system can be a challenging project because speakers and components are designed for specific vehicles. Working in tight spaces can also be difficult. You can rebuild the entire system or replace components in stages starting with speakers, the most important part of a good system. This article provides product and installation resources for building a car stereo system.
Car Stereo Speakers
Like home audio, speakers are the most important part of a car audio system. Speaker type, size and shape, mounting location and power requirements are important considerations for a car audio system. First, find out which speakers will fit in your car. Consider front, center and rear speakers for a complete system. With some speakers, an enclosure will be needed.
Next, match the power handling capacity of the speakers with the power output of the amplifiers or head unit. Make sure to include crossovers for midrange speakers and tweeters.
Car Stereo Subwoofers
Subwoofers require more power than other speakers and an enclosure when installed in a car. You can make a custom enclosure or buy an enclosure designed for your model car. There are many types of subwoofer enclosures to consider based on the size of the woofer and the type of vehicle. The most common sizes for a mobile subwoofer are 8″, 10″ or 12″.
Some manufacturers offer amplified subwoofers with enclosures, which can be easily installed in the trunk or behind the seats in a pick-up truck.
Car Stereo Amplifiers
Most head units have built-in amplifiers (typically about 50-watts per channel), but external amps with more power are usually best because you can adjust the level of the bass, midrange and high frequencies separately for a balanced system. Also, a subwoofer requires more power than a midrange or tweeter. You could also consider a separate amp for the subwoofer and use the amps built into the head unit. Using separate amps also requires crossovers between the amps and speakers to distribute the amp’s signal to the correct speakers. Some amps come with crossovers.
Car Stereo Head Units and Receivers
When building a system, you can use your existing in-dash head unit (or receiver) or replace it with a new component. However, the downside is that most factory head units don’t have pre-amp outputs so you cannot use external amps. There is speaker level to line level converters, but these tend to sacrifice some sound quality. If you are replacing the in-dash head unit, the chassis size is important to know. There are standard and oversized head units available. A standard size is known as single DIN; oversized units are known a 1.5 DIN or double DIN. Also, consider if you want a cassette player, CD or DVD player, with or without a video screen.
Car Stereo Installation
Installing a new car stereo system can be tricky, but if you have the tools, a good knowledge of electronics and the patience, go for it! If not, have the system installed by a professional. Consider the affect (if any) on the vehicle’s factory warranty or extended warranty by consulting your car dealer, and think about your time and expertise. There are many companies that provide installation services, or you can consult an online guide to car stereo installation.