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If you have been around the mobile electronics industry for more than a decade, then you may have noticed some significant changes. New technologies make our time behind the wheel safer, more entertaining and more productive. Many products offer better performance and efficiency compared to their originals. Innovations and technological advancements let us do things that simply were not feasible decades ago. This article looks at some of the most significant changes that have taken place in the car audio industry over the past few decades.

The Mighty Head Unit

Let’s see how far you want to go back. Mono FM radio? The 8-track? Perhaps a turntable under the dash of your 1960 Chrysler? Things have come a long way in source units and their features. We saw cassette players, the mini-disc (if only for a year) and even CD players come and go. We introduced digital media with MP3 files, then added WMA, WAV and – most recently – FLAC file playback. Soon, Master Quality Authenticated (MQA) will join the ranks.

The introduction and popularity of the Apple iPod signaled a massive change in the philosophy of music lovers. While this handy device could be considered the “nail in the coffin” for the record store industry, it launched new levels of convenience for music accessibility. The mobile electronics industry embraced the iPod, and now, support for it is standard on all mid- to high-level source units. Similar support for Android-based smartphones has also become almost a standard feature in the last few years.

Miniaturization and the advancement of computer processing have given us full-color touchscreen interfaces with fancy animated graphics. We can watch a DVD or digital media movie while having lunch in the car. Portable navigation systems have replaced paper maps to help us travel safely and more efficiently.

Recently, we have introduced connected technology solutions. Internet connectivity is a feature in many new car radios, most often via your personal smartphone. Access to the Internet allows you to stream music from online resources like Google Play or iTunes Radio. Apple and Android have developed interfaces for their smartphones to enable drivers to send and receive text messages, make phone calls, select navigation destinations, and choose the music they want to listen to by just talking to the radio. CarPlay and Android Auto are the current “big thing” in multimedia source units.

Those Oh-so-fun Subwoofers!

What could you change when it comes to the design of a speaker? Materials for cones, suspensions, surrounds and motors haven’t advanced all that much, and because a subwoofer reproduces only low frequencies, things like cone materials don’t have a dramatic effect on performance. What has changed is our ability to model the behavior of the magnetic field within the speaker. Being able to optimize the geometry of the magnetic field allows designers to create subwoofers that are more efficient and that offer better performance with less distortion at high excursion levels.

The size and location of the subwoofer enclosures we use in our vehicles have become and more important. Back in the “good old days,” if you wanted big bass, you had to give up your trunk. Now, many subwoofers are designed to play nice and low in a very small and shallow enclosure. Using these subwoofers allows your installer to create compact solutions that will fit in a spare-tire well, the corner of your trunk or even in the footwell of some vehicles. We should be clear; there is a trade-off with these subs – they often require more power to produce the same output as a “conventional” subwoofer, but power is inexpensive these days.

Amplifiers, Smaller, More Power

Power is cheap. You can buy a great-quality 1,000 watt subwoofer amplifier for around $500. Decades ago, a 1,000 watt amp was among the biggest amps available, and it cost several thousand dollars. That amp was also the size of a skateboard and consumed a lot of power. Modern amplifiers are much smaller and much more efficient, sound better and consume less power. A lot of people credit the increase in efficiency to Class D designs. While switching to Class D for many applications makes sense, there have been efficiency improvements thanks to being able to use small microcontrollers and high-tolerance components in a Class AB amp.

In the past few years, more and more companies have been offering amplifiers with built-in advanced signal processing. On the most basic of amplifiers, we have crossovers and bass boost circuits. More advanced amplifiers offer both high- and low-pass filters on the same channel for midbass and midrange applications. Some amplifiers even provide low-frequency signal restoration processing. A whole other class of amplifiers on the market has built-in DSP processing. Some are so advanced that they don’t have a single analog adjustment on them.

Signal Processing Moves To Digital

Years ago, signal processing meant you had an EQ and a crossover in your car. These in-dash processors were made popular by the 1/2-DIN equalizer – a 1×7-inch EQ that would mount in the dash above or below your radio. These little EQs offered as many as 11 bands of graphic equalization to let you “tune” your system. Some had subwoofer level controls and crossovers built in.

The next step in processing was the stand-alone processor – usually either an equalizer or a crossover, sometimes both. These were the size of a medium-sized hardcover book and gave installers much more precise control over system tuning. The drawback was their physical size. They took up a lot of room.

Almost all of these are gone now, replaced by stand-alone DSP processors. These seemingly magic black boxes replace those old stand-alone equalizers and crossovers, and include options like signal delay and the ability to switch between different settings at the flick of a switch.

Modern signal processing has allowed installers to use signal delays to optimize seemingly unconventional mounting locations for speakers to produce an amazingly accurate soundstage.

Speaker Placement Becomes Less Critical

In the past, if you wanted a great soundstage in your car, then you had to work with placement to equalize the difference in path lengths between the front speakers. Autosound competitors would go to great lengths to move seats as far back into the vehicle as possible, and some even built vehicles with a single seat located in the center. It was all somewhat silly because that effort never translated into value or performance for the consumer. All consumers could get were kick-panel–mounted speakers or a compression horn under the dash to aid in equalizing distances.

With the assistance of modern signal processing, installers can use factory locations, then delay the signal going to the closest speakers to put you in the center of them.

Another speaker location that has become popular is the A-pillar speaker pod. A nice midrange and tweeter up high and far forward in the vehicle can help create a deep and wide soundstage. The drawback with this approach is that it only works for one seat. If it is set up for the driver’s seat, the soundstage for the passenger seat is compressed into the right-side speaker location.

Very soon, the newest of processors will offer provisions to make every seat in the car sound great using an up-mixer and a center channel, just like the one in your home theater. Now, both front seats and even passengers in the rear can experience an even and focused soundstage across the dash of the vehicle.

Modern Speakers Refined

Like subwoofers, speakers haven’t changed dramatically since the first fixed-magnet, moving-coil speaker was created in 1925. Speakers have improved in efficiency and accuracy thanks to better materials for surrounds, better adhesives and dramatically better processes that help speaker manufacturers build more-consistent products. The real performance upgrades have come in the optimization of a speaker’s motor assembly with respect to the interaction between the voice coil and the magnetic field.

As a speaker cone moves in and out, the magnetic field strength varies. This causes distortion. The same goes for the suspension system: Being able to model the behavior of different surrounds and spiders allows designers to produce transducers that are more linear and, thus, create less distortion.

The Incredible Car Audio Evolution

Overall, the latest innovations and technologies have moved the mobile electronics industry to a point where the modern in-vehicle infotainment system performs at a level that could not be conceived of even a decade ago. If you want to find out about the latest technologies or products, drop into your local mobile electronics specialist. They would be happy to show you the latest and greatest offerings for 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.

When it comes to bang-for-the-buck upgrades to any audio system, none can beat the dramatic difference of adding a subwoofer. Factory audio systems are getting pretty good at producing a soundstage in front of the listener, and they are EQed well enough not to be painful to enjoy – but one thing they all have in common is anemic, wimpy, thin and muddy bass response. Adding a quality subwoofer system can fix that.

What are optimal subwoofer system enclosure locations? If you think of the stereotypical car audio system, the subwoofer enclosure was usually something that took up most of the trunk or hatch area of the vehicle. You’d pop the trunk, and there would be just enough room for a knapsack or maybe a duffle bag. Did these systems sound great? Absolutely! Did they leave room for golf clubs, luggage or a keg of beer? Not a chance!

Subwoofers for Compact Enclosures

Looking through recent photos of custom car audio installations will reveal that subwoofer enclosures no longer take up space they once did. Why is this? Companies that design and manufacture subwoofers are conscious of the need to provide amazing performance without taking up a lot of space. There are now dozens of subwoofers designed specifically to fit into very shallow locations – like behind or under the seat of a pickup truck. These same subwoofers are also designed to produce deep bass from minimal enclosure volume requirements.

When a company designs a speaker, they have to balance three basic performance criteria – low-frequency extension, efficiency and enclosure volume requirements. In general terms, you get to pick two, and the third will suffer. For a small enclosure driver, it’s often efficiency that takes a small hit. Regaining some of this reduction in output is credited to careful and thoughtful computer modeling and the use of stronger magnets and tighter tolerances withing the motor assembly of the subwoofer. Efficiency isn’t as important as it used to be – we have many high-power amplifiers that don’t cost an arm and a leg.

Conventional Enclosure Locations

If you drive a hatchback or SUV, a subwoofer sitting behind the rear seat is still very common. This location works quite well because the output of the subwoofer system is in the same listening environment as it would be in a sedan. Your installer may choose to face the subwoofer in almost any direction – rearward, forward, up or down. Firing the subwoofers down into the floor can act as a bit of a filter for high-frequency energy, so your midbass speakers have to be up to the challenge.

If you drive a sedan, your subwoofer system is probably at the back of the trunk against the rear seats – much like in hatchbacks or SUVs. Again, the direction in which the speaker points varies based on the system design and cosmetic layout. Firing the subwoofers forward provides room to mount amplifiers and processors on the rear of the enclosure.

Another popular application for sedans is to fire the subwoofers through the rear deck or ski pass-through between the seats. These techniques dramatically improve the midbass response from the subwoofer and ease the requirement for large midbass drivers in the front of the vehicle.

A Little Custom, A Little Fun

Working with unique locations can offer a dramatic increase in the available storage area in the vehicle. There are two classic locations for a custom subwoofer enclosure: in the spare tire well or the corner of the trunk or storage area.

The spare tire well of many vehicles can offer an amazing amount of space for subwoofers. In many cases, a skilled installer can include your amplifiers and processors in that same space. Some thoughtful design and careful planning can leave you with your entire trunk available for cargo. You do need a plan for not having your spare tire with you – but the local auto service is always a phone call away.

Building an enclosure in the corner of your trunk can offer excellent performance without a dramatic effect on available cargo space. Installers love to get creative with these enclosure designs. Classically, these enclosures have been molded to the vehicle with layers of fiberglass. Layered fiberglass construction offers excellent use of space, sometimes allowing for a larger subwoofer to be used with the same low-frequency performance, or even for a vented enclosure design. The drawback to fiberglass can be the time it takes for construction, and the smell. Fiberglass resin has a strong odor. It won’t last long, but that aspect is worth keeping in mind.

Another construction technique that is becoming more and more popular is stack-fab. The stack-fab process uses multiple layers of wood. Each is cut to fit the contour of the vehicle, then glued one on top of another until your installer has built up to the top of the desired space. Stack-fab construction can be quite efficient in terms of time. The enclosure is ready to go right away. There is no waiting for layers of fiberglass and resin to dry. Stack-fab isn’t as efficient on internal air space, but produces a very rigid and well-damped result.

Unique Applications and Solutions

What if your vehicle is a little more challenging than most? Say you have a small two-seater like a Miata or an NSX, but want great sound? There is no room behind the seat for anything. What’s an auto sound enthusiast to do? The passenger side footwell can be a great location for a subwoofer. A skilled installer can get a good-quality 8- or 10-inch subwoofer in there while leaving more than enough room for the passenger to sit comfortably in the vehicle.

Wherever you and your installer decide to place your subwoofer enclosure, the addition of good, solid low-frequency musical information will dramatically improve the overall performance of your mobile audio system. Search the Internet and join one of the many car audio groups on Facebook to gather ideas. Once you have a few thoughts, talk with the product specialist and installer at your local mobile electronics specialist retailer. No doubt, the result will be amazing!

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.