RESOURCE LIBRARY

Since the late ’80s, the car audio industry has experienced incredible levels of growth. New technology and features have expanded our opportunities to increase sound quality and enhance entertainment. What hasn’t changed are the core building blocks of how sound systems are designed.

Every system starts with a source. We call this the head unit, source unit or radio. In more than 99.9% of vehicles, the source unit includes an AM/FM receiver, along with a CD player or USB port to play digital media files like MP3, WMA, AAC and FLAC files. The source unit also typically contains the volume control for the system.

It used to be that a new source unit was the first component that would be upgraded on the path to improving the sound system in a vehicle. From the perspective of a quality improvement, this is becoming less and less common. Read on to find out about the benefits and limitations of replacing the factory radio in your vehicle.

Can I Make the Switch?

Look at a vehicle like a BMW, Audi, Mercedes-Benz or even a Mazda. Their radios are not stand-alone units at all. The Mazda 3 is an excellent example of a modern distributed source unit. There is a screen on the dash, a CD mechanism below the climate controls and a control panel in the center console. None of these components matches any size standard for an aftermarket radio. If you want to upgrade the sound system in this vehicle, you will not be buying a new radio.

Thankfully, this radio has most of the features that people want. CD, MP3, SiriusXM, an auxiliary input and Bluetooth audio streaming are readily available signal sources. The system includes hands-free calling and a built-in GPS-based navigation system.

Sadly, though, the system does not include Apple CarPlay or Android Auto smartphone integration.

Can We Integrate?

If we want to upgrade the sound system, a mobile enhancement retailer can connect an amplifier and new speakers to the signal coming out of the radio. With some fine-tuning and a well-executed speaker installation, the quality of the system will improve. You will also be able to turn your music up louder.

If you want to take things to the next step, then add a digital signal processor (DSP) to give your installer all the tools required to flatten any peaks or dips in the system’s frequency response and adjust for different path lengths between the listening position and your speakers.

The Sound Quality Upgrade Path

Let’s look at another popular compact car: the Subaru Impreza. Subaru manufactures durable, reliable vehicles, but their sound systems are not at the forefront of technology. In fact, several models of the Impreza are begging for sound system upgrades. Luckily, improving the sound systems in these vehicles is easy. Let’s look at what’s lacking and how to fix it.

Add Bass, More Power and New Speakers

The recipe for improving the performance of an audio system does not vary much from vehicle to vehicle. The first step most retailers will recommend is to add an amplifier and a subwoofer. Adding a subwoofer will not only bring more bass to the system to make it sound more lifelike, but alleviates the need for the smaller speakers and factory amplifier to try to reproduce those frequencies. The result: Everything sounds better.

The next step is to add more power to the factory speakers with an amplifier. Many people will combine the addition of a subwoofer with a multichannel amplifier that can power the factory speakers at the same time. Five-channel amplifiers are an excellent choice for a single, easy-to-install upgrade. Multichannel amplifiers have built-in crossovers that will eliminate bass information from the smaller speakers, so they sound better.

The last step in upgrading the sound system is to replace the factory speakers. Now, if you have listened to a factory Subaru stereo, this might be your first step. There is no right or wrong when it comes to the upgrade path you take. Keep reading to find out why we often leave this step to the end.

We often suggest upgrading the speakers last because high-end speakers aren’t typically as efficient as the cheap speakers that come from the factory. New speakers provide smoother frequency response and much less distortion, and can handle a lot more power and play louder. When connected to a factory radio, there isn’t have enough power to experience all of the benefits of the new speakers. A speaker will only play loud when it is driven with adequate power.

Wait – What about the Radio?

You will notice that nowhere in the upgrade path did we suggest replacing the radio. The factory Impreza radio has a reasonable feature set and provides perfectly flat frequency response that we can use to improve your system. When looking at the goal of improving the sound quality of the system, the source unit is the last thing to change (unless you want to add high-resolution audio playback).

I Want More Features!

We touched on Android Auto and Apple CarPlay. These technologies, along with Siri Eyes Free, FLAC file playback, Pandora and much more, are great reasons to upgrade a factory radio. However, these are not specifically performance improvements – they are feature enhancements. We could nit-pick about FLAC files sounding better (in a future article, we will analyze high-resolution audio in great detail.) If you want better sound, all the other upgrades offer a larger increase in performance for your investment than an aftermarket source unit.

Experience Better Sound

When it comes time to upgrade the sound system in your vehicle, visit your local specialty mobile electronics retailer. Let them know what your goals are for the system and work with them to design something that meets your expectations and your budget. Following our suggested upgrade process can yield impressive improvements with a reasonable investment at each step. Each upgrade will produce immediately audible benefits.

Have fun improving your mobile sound system!

This article is written and produced by the team at www.BestCarAudio.com. Reproduction or use of any kind is prohibited without the express written permission of 1sixty8 media.

It may seem as if they should be similar processes, but installing a new source unit, amplifiers and speakers in a car is unlike installing most home audio systems. It is not as simple as plugging things in and hoping they work. Proper integration of your new electronics into modern vehicles and their wiring is getting more and more complicated as complex factory sound systems become more involved. One thing that hasn’t changed, though, is the need to configure the equipment you have selected. Your installer will include this setup time in the cost to install your system. What does system setup and configuration involve? Read on to find out.

Signal-level Adjustments

When it comes to adding an amplifier to your vehicle, the most significant adjustment your installer will make is to adjust the amplifier’s sensitivity or gain control. Amplifiers have these controls so they can be compatible with a variety of different source units with different maximum output voltages.

Amplifiers are relatively simple devices in concept. They take an audio signal from your source unit and increase its voltage so it can drive a speaker. A 100 watt amplifier has to be able to increase a 1 volt signal more than a 4 volt signal to reach the 20 volts required to produce 100 watts into a 4 ohm speaker. The gain or sensitivity control lets us adjust for almost any source unit voltage.

Why Sensitivity Adjustments are Important

If the sensitivity of the amplifier is set too low, you will not be able to get the full power of your amplifier. If it is set too high, then you can drive the amplifier into distortion quite quickly. Too much “gain” can also add noise to the system in the form of hiss. A little extra is OK to allow quiet recordings to be played loudly, but too much is a surefire sign that whoever set up the system did not fully understand gain structure.

System Setup Tools

Different shops use different techniques to set gains on amplifiers. Some use an oscilloscope along with a set of test tones. Others use distortion detection devices like the SMD DD-1 or DD-1+. Finally, some installers are quite adept at setting up systems by ear, but that comes with years and years of experience.

As long as the system plays loudly without significant noise or distortion, the settings can be considered correct. If the system runs out of power at half-volume, then it needs some more adjustments.

Crossover Adjustments

There are two main advantages of adding a subwoofer to an audio system. A subwoofer provides more bass output than a typical set of door speakers could ever hope to produce. The secondary benefit is to relieve the small speakers of their requirement to try to produce bass. This reduction in bass reduces the distance the speaker cones have to move and directly reduces the potential for distortion. Midrange frequencies can be reproduced with improved clarity and at higher levels.

Tying this back to system tuning, how we set the crossovers built into your amplifier is crucial to ensuring that the output of your system blends perfectly between the midrange speakers and the subwoofer. If the crossover points overlap, there can be too much midbass, and the system will sound boomy or “honky.” If the crossover points underlap, the system probably won’t have enough midbass and will sound very dry and flat; the subwoofer can also sound “separated” from the system, reducing the coherence and realism of your music.

Speaker Polarity Adjustments

Because each vehicle is different, sometimes the direction a speaker faces requires that we wire it in reverse polarity for the output to combine properly from an acoustical standpoint. This requirement is very common with subwoofers, since they are often pointed in the opposite direction from the smaller interior speakers. Properly trained and equipped installers know how to measure the frequency response of a system and correct for that. In most cases, an audio analyzer is the best choice for setting up a system. These can be stand-alone units from companies like AudioControl and NTI or software-based solutions that work with a laptop, netbook or tablet.

Left-to-right speaker polarity, and the polarity between midrange drivers and tweeters, depends on placement and crossover slopes. These regions deserve analysis before a car leaves the install bay.

Leave It to the Experts

A properly tuned sound system will play louder, last longer and be much more enjoyable to listen to. As you can see from even from this overview, the tools and training required to maximize the performance of even a simple mobile sound system can be expensive and complicated. The staff at your local mobile enhancement retailer should be familiar with these processes and employ them on each installation they perform. Confirming this is part of your process in selecting a retailer that is qualified to work on your vehicle.

This article is written and produced by the team at www.BestCarAudio.com. Reproduction or use of any kind is prohibited without the express written permission of 1sixty8 media.