|
From YourSITE.com Technical Features Audi’s S-cars are some of the best all-round vehicles anyone could hope to own. With few choices upon ordering, everyone seems to think getting all the options means getting the best. This is especially so when you consider the latest B7 S4 as we did with our 05.5 model year subject of this series and its then-new Audi Navigation+ system paired with satellite radio and the old standby high end Bose speakers. However, when it came ordering this particular B7, those options were purposely left off the check list, not because of the added cost but rather due to our modification priorities. Being ordered by an audio buff, these components were redundant as they’d soon be replaced.
Building the Amp Rack and Sub Enclosure Fortunately for the stereo build, trunk space for the S4 is enormous. Some would suspect this creates a great environment in which to plan a large system. However, the S4 has been a favorite in our minds because it is not only a great mix of sport and luxury, but it’s also a car that can handle a weekend at the track as well as a family of four heading out on a weekend getaway. Maintaining 85-90% of the available trunk space was a high priority. A mark of success would be having someone do a double take and wonder if the system was aftermarket or some special package Audi offered from the factory. The trunk’s carpeted side panels were used as a template for a plywood base on which fiberglass racks would be built. After mocking up the locations and sizes of the components, weeks went into fiberglass formation, body filling, sanding and painting. Panels were finished with the same Sprint Blue pearlescent paint that graces the exterior of the car, finished with a clear coat that is a mix between satin and semi-gloss. This was done to minimize glare and potentially taking away aesthetically from the forms of the panels. This was also done to compliment the machined and satin look of the subwoofer and amplifiers. Completing this part of the project couldn’t have been done without the skill and expertise of this author’s brother Sean, who put in plenty of his own time over his school’s spring break to help create the main focal point of the system. His time and effort were greatly appreciated.
The Audiobahn 10" Pro Compression Piston subwoofer was chosen for its compact size, excellent performance, great build and good looks. Regardless of its compact nature, this unit still needed a full square foot of airspace in order to work properly and that volume of air is hard to find. Making the enclosure for this airspace proved to be the most difficult part of the installation. On the driver’s side of the trunk, right behind the wheel well is the location chosen for this air enclosure. Most people would associate this air space with the prefabricated subwoofer boxes sold at any car audio store. Creating a custom enclosure is difficult and creating one that will fill the freeform space behind the wheel well of an S4 certainly isn’t any easier. Fiberglass was laid into the space to help create a rough formwork from which to build the enclosure. The enclosure was built in a similar fashion to the amp racks but has many more layers of fiberglass because the enclosure physically needs to stand up the high pressure created with every thump of the subwoofer. It was then finished off with mounting points that utilize stock locations in the rear, mounting points originally used for the storage box located in that same position.
This enclosure is easily the most important and most difficult part of the entire system and, at the same time, plenty of effort went into hiding it in otherwise dead space. No one will ever see it again, yet its purpose is served with every note the pumps through the stereo. Wiring and Sound Proofing In order to get the most out of this system, the wiring needed to be upgraded and soundproofing installed. The wiring that was selected was sourced from Monster Cable, whose top of the line 404 XLM Series was chosen for its large gauge and heavy insulation that guarantees the wiring won’t be the weak link of the system. The only problem with this amazing wire is its size. The speaker wire most people are familiar with in car stereo installations is only about 1/16” in diameter, though this Monster Cable is close to 1/2” which makes hiding it that much harder. All wiring (speaker cable, power wire, RCA cables from stereo) were installed down both sides of the car under the carpet near the door sills. Although locating all of the wiring was not an easy task, the main difficulty occurred when trying to get the speaker cable through the door grommets and the power wire through the firewall.
To get the best performance out of any speakers, soundproofing helps increase the efficiency of the amplifiers by reducing the sound transmission through the doors and trunk. Dynamat Xtreme was used to cover all four doors behind the door panels and was also used behind the subwoofer enclosure in the wheel well of the trunk, as well as under the carpet of the trunk lid. Dynamat is relatively easy to install, as it’s basically a peel and stick, self-adhesive, aluminum backed rubber material that reflects the sound waves back into the car and helps reduce vibration and noise. Dynamat Xtreme can add as much as 12dB and by helping preserve only 3dB doubles the effective power output of your amplifier. In simpler terms, this means that you can get a lot more out of any amplifier you can afford, and helps you run those amplifiers more efficiently. This generous amount of Dynamat does add some considerable weight. It’s for this reason the Xtreme mat was used over their original mat as it weighs 50% less and, as another benefit, is four times more effective at damping sound. A total of roughly 20lbs was added in Dynamat (2.7lbs per door and 9lbs in the trunk). Speakers The sound of the stock stereo system is fine for the average radio listener and the upgraded Bose system is more than enough for those that want a little more than most factory systems offer. However, even the Bose system presents limitations on the stereo and adds further difficulties if you wish to pair it with an upgraded aftermarket head unit or subwoofer. Going for a full system replacement, the speakers chosen for this project were the Infinity Kappa Perfect components with a custom speaker plate for the 6.5” woofer and a little modification to the tweeter plate located in the door panel. The passive crossover which directs the mids and highs coming from the amplifier to the correct speaker fit nicely in the door panel with a little bit of Velcro.
What makes aftermarket speakers like the Kappa Perfect’s so much better than stock is that they’re built of higher-grade materials and can handle much more power. The cones of the speakers are made of aluminum rather than a paper-like material found in more OEM applications like our car’s stock speakers. The stock speakers don’t sound bad until you pump up the volume and leave them at a high level for a long period of time. As the speakers get hot, the sound gets muddy. The Kappa Perfect’s can be left at a high level all day and they’ll still sound crisp and clean. The key to our subtle installation speaker setup was finding a way to utilize the stock speaker locations and mounts. Since these locations aren’t set up for the standard sizes of which aftermarket speakers are designed, special brackets needed to be created to allow for proper mounting. To make these brackets a template of the stock speakers was made and transferred onto 1/4” plywood. On top of this plate, rings of MDF (Medium Density Fiberboard) were created in order to mount the speakers at the proper height. The stock speakers have a rubber gasket between the metal of the door and the speaker itself and between the speaker and the door panel in order to reduce vibration and to direct as much sound as possible into the cabin. The stock rubber gasket was cut off and glued onto the custom speaker bracket and foam bead sealant (typically used to fill cracks too large for caulk) was used around the speaker in order to mimic the seal of the stock speaker to the door panel.
Head unit and Faceplate The Pioneer Avic-N1 was chosen or its multipurpose uses, including not only a navigation system, but also controls for CD changer, XM radio, XM NavTraffic tuner, DVD player and additional auxiliary inputs for things like a video game console. It even has output for video to be sent to headrest or trunk mounted monitors. The advantages of the Avic-N1 extend beyond the features above. First and foremost the system is controlled by a touch screen and can be easily controlled by voice commands. Another cool feature set of the Avic-N1 is that it also measures vehicle dynamics such as acceleration, braking, cornering, slope, direction, as well as a speedometer which is fed by both the car’s speed signal and the GPS signal which makes for an even more accurate speed indication measured to 1/10 of a MPH. The final touch to the head unit install was to make a faceplate for the single din sized stereo head unit to fit the proprietary sized opening of the Audi Symphony unit which had been replaced. A faceplate was moulded out of carbon fiber to match the carbon fiber beltline trim found throughout the car. The aluminum strip from the stock Symphony unit was removed and screwed to the bottom of the faceplate to break up the dark color of the center console, used just as it was originally designed. Conclusion The purpose of this install was to not only improve the stock stereo that came with the B7 S4, but to offer more functionality than the upgraded Bose and Navigation Plus options that also could have been ordered for the car. In the trunk, the goal was to retain as much space as possible in order to retain the functional benefits of the vehicle. As is common with this type of install, the project turned out to be a lot more involved than originally anticipated. However, the end results were also better than originally anticipated. It wasn’t the easiest task in the world to tackle such an ambitious project on such an expensive and refined car like the S4, but there’s no feeling like that of accomplishment when it was completed. The B7 S4 is a great car right off the showroom floor and it’s easy to screw up the overall purpose of the car. However if done right and with a little luck and design sense, you may just be able to create something that compliments the S4 for and improves on one area where stereophile think this German muscle car comes up short.
© Copyright 2004 by YourSITE.com |
