True Multi-channel Audio in Cars

In-Car Entertainment, or ICE, is big business these days. From the days of the humble radio, car audio systems have now evolved to include enveloping surround sound, bone rattling bass, and video display screens. What does it all require, and is it really worth the time and effort?

Yes, if you ask car audio enthusiasts who love nothing more than having the best sound that they can get from their cars, especially if they spend a good part of the day driving around town or traveling long distances. Regular car fitted stereo systems usually comprise of between two to four speakers and a single head unit. Modern head units play a combination of CDs, MP3, cassette tapes and may feature an optional adapter for portable storage devices like the iPod. The head unit also functions as an amplifier in basic systems. If you bring it up a notch, you can install separate power amplifiers for louder and better sound, as well as separate speaker drivers to accurately reproduce different the spectrums of the audio range. Typically, small dome tweeters are used for treble or high-end, mid-sized cones for the mid-range, and an individual subwoofer is used to reproduce the bass.

The trouble is, conventional stereo recordings have only two channels of audio, a left and right channel. When played through a properly aligned playback system at home, the music reproduces the proper stereo image. Yet cars tend to have multiple speakers mounted throughout the interior, and there is no way to reproduce an accurate soundstage and the audio just seems to be swimming all around you. In a properly imaged home system, you can clearly hear the vocalist centered in a precise point between the left and right speakers. In car audio systems, the vocalist seems to be all around you! Suffice to say was not the representation the original record producers intended. While home theater systems sporting true multi-channel surround sound have been commonplace for years, Multi-channel surround sound for automobiles is still in its infancy, mainly because of the lack of playback material and decoders. Coupled with the fact that true surround sound is often found only on movies, bringing surround into the realm of car audio can be a little tricky.

Now, Pioneer has upped the game by introducing the world’s first front loading 6-DVD changer with a 7 inch touch screen display that also doubles as a video screen. The player features Dolby Digital decoding for true multi channel surround sound while playing DVDs in the car, and is essentially a home theater receiver scaled down for automotive use. Their car A/V series also features the range topping Pioneer AVH-P7850DVD, which has 8 channels to allow full Dolby Digital EX capability in the car, and the motorized LCD screen has the ability to be converted into what they term as ‘Vehicle Dynamics Processor’ screens. This essentially means that you can do away with all the additional performance dials that clutter your A-pillar, as the LCD display will show you digital dials that read out data like G-force, RPM, torque and current horsepower output.

Screening movies in a car is a good way to keep kids occupied during a long road trip, but there are many design factors that make the interior of a car a difficult place to try and convert into your own mini theater. Pioneer claims that with a proper installation, their system recreates DVD soundtracks with a clarity and precision to rival the best movie theaters in town. Yes you can have big sound in the car, but remember that the video screen is less than 7 inches wide! The audio cues will never match the action happening onscreen, and the soundstage will always be wider than the image, but the system can come into perfect sense with used to playback DVD audio discs, of which many are surround enabled.

Is it worth the upgrade? True ICE addicts, gadget-philes and audioheads will no doubt jump at the chance to install a mini cinema with true surround sound capabilities into their cars, but I’m still waiting for the day when someone invents a way to design a video projector that uses the car’s windscreen as a video screen. Then I would be able to drive anywhere and have my very own drive-in cinema in the car.

Credits: Lionel Kong