Here's another fairly simple way to improve your car audio quality: sound-deadening materials. In most cars, the speakers are mounted in the front doors and behind the rear seats, usually facing up towards the rear window. The vibrations from these speakers can actually shake the car (or parts of the car), which can be noisy and will generally reduce the quality of the sound.
Sound deadening materials like Dynamat -- a cut-to-fit sheet of noise reducing material -- can absorb these vibrations when it's properly installed in your vehicle. Materials like Dynamat create a more stable platform to support the speaker, so the quality of the speaker won't be impaired by its own vibrations.
At the same time, Dynamat, or similar system, will reduce the noise from the road itself. If you have a small car or even a larger car that has thin doors or poor insulation, you know how loud road and wind noise can be at highway speeds. With a sound deadening material in place, you won't need to turn your volume quite as high to compensate for excessive road noise [source: Dynamat].
Up next, we'll look at how car audio accessories like amplifiers and head units can improve your audio quality.