tech today
The 12-volt tech guru is back to cover the nuts and bolts of how to mount one an amplifier in the roll cage of a 1988 BMW E30 M3 and tricks to mount amps in other difficult locations.
WORDS BY JOEY KNAPP, SIMPLICITY IN SOUND
A
mplifiers are a key component to a great sounding audio system. I believe amplification is even more important in the mobile environment. In a home audio system, there is a very low environmental noise floor. Because of the low noise floor, a marginal amount of power is needed to provide good resolution in the audio playback. In addition, home audio speakers are much more efficient than their mobile counterparts. The automotive environment is very different than the home environment. Even a parked car with the engine turned off is susceptible to much more external noise than a home. Cars don’t have the benefit of dense building materials, heavy insulation, or double-pane windows. Starting the engine in a car will typically raise the noise floor in addition to adding a bit
48 Mobile Electronics January 2016
of tactile distraction. We own cars to be able to drive them. Whether for utilitarian purposes, or for enjoyment, at some point most every car will be moving. That movement brings in a whole other realm of noises to the vehicle cabin. Wind noise and road noise are two of the biggest enemies to a low cabin noise floor. Sometimes soundproofing can help address some of these issues, but they will never disappear completely. So, to have a great sounding audio system in a vehicle, an amplifier is paramount. Amplifiers help increase the signal level to overcome many of the typically present automotive interior noises. Over my many years in car audio, I have installed hundreds of different amplifiers. The amplifiers have ranged in output from a few watts per channel, to thousands of watts. The locations in
which the amplifiers are installed are usually narrowed down to the floor of the vehicle (whether the trunk or under a seat), under a rear deck of a trunk (leaving the trunk space useable), or the side or back panel of a trunk. Recently, though, I had the opportunity to install an amplifier in a place I had never before installed one. The location was the roll cage of a car. The car I worked on was a 1988 BMW E30 M3. The owner of this car is Sam Yang, owner of Southern California surf brand, VAST. Sam’s car is a motoring icon. It was the first generation that BMW offered with the M package. Initially, the E30 M3 was a homologation special. They produced a limited number of the cars so that they could, in turn, be able to race a version of the car. The M series had different body panels, brakes,