First off let's get it out of the way, my definition of great car audio is probably different from yours.
But, as you read the following pages you will understand that you can use the basic principles here to achieve your own definition of Great Car Audio.
What I call GA (Great Audio) is Hi Fidelity accross a wide frequency range with a realistic soundstage.
Sounds complicated doesn't it? Well it can be but I think I can make it a lot simpler for you to acquire.
First let's tackle Hi Fidelity. We need to have a source for our sound, in this and most cases, an in-dash CD player. This is the beginning of our audio chain and must output very, very clean sound.
Without it the whole system will sound like crap. Garbage in/Garbage out. Next this sound must have a way to travel to the next step, either the signal processor or directly to the amplifier. This means having high quality shielded interconnects.
Once through these interconnects, we wind up at our amplifier(s). This is where things get really scarey. Most car amplifiers sound like tin foil on a comb in comparison to the (hopefully) clean power coming out of your home stereo system.
We need to have an amplifier that has enough power to drive our speakers and low enough distortion not to kill them with obnoxious buzzing and popping called distortion. From here we need good quality speaker wire for this now GREATLY amplified signal from the CD player
to our final destination - the speakers. Speakers are the part of the audio system we actually hear (unless you blow up something). They need to have a relatively high sensitivity (90+dB), low distortion(again) and reasonable power handling capability, while all the while producing the
frequency range we need.
Which brings me to the next point, Wide Frequency Range.
In this dream system of ours, we are going to want to cover as much of the human hearing spectrum as possible. The upper and lower limits of this in most cases, is 20Hz on the low end to 20 KHz on the high end. To my knowledge, there has never been a single speaker manufactured
that can cover this range on it's own, so we won't even discuss single speaker per channel systems here. Our system will be comprised of 5 or 6 speakers for the sake of argument and can be expanded as long as you follow the procedures.
Those 5 or 6 speakers are: one or two subwoofers, two midbass/midrange drivers and two tweeters.
(Keep in mind you can have multiples of these drivers as long as you balance the sound correctly. I am just going over the basics)
The subwoofer enclosure will need to have an F3 of around 35Hz or so to be able to have good audible (provided you can hear this low) output to 20Hz. This is not always the case but is a good design goal. We will cover more about subwoofer design in another chapter.
The midbass/midrange drivers will need to cover from the upper limit of our sub enclosure (usually between 80 and 120 Hz) to low cutoff of our tweeters (usually around 1500 to 5000Hz). Our tweeters will pick up from the upper end of our Mids and extend out to our theoretical high end - 20 KHz.
Now that we have covered these design goals, it is time for our final stipulation for having GA: proper soundstaging.
Soundstaging can best be described as being able to close your eyes and picture where in the room or on the stage the musicians were standing when they recorded this CD. We will achieve a realistic soundstage through proper positioning of the individual speakers, phasing and correct crossover points for the speakers we are using.
