Better car audio, Tip #4: Add a signal processor or an equalizer
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Welcome to this article from the Crutchfield archives. Have fun reading it, but be aware that the information may be outdated and links may be broken. 
A car interior presents some serious problems when it comes to sound quality. Glass and plastic surfaces reflect sound like crazy, while carpet, seat covers, and other absorbent materials soak it up. Add poorly-placed speakers to the mix, and you'll find significant peaks in frequency response in most car interiors. These peaks make your music boomy in the bass or shrill in the upper frequencies, causing "ear fatigue."
Most car receivers give you treble, midrange, and bass controls - useful for global fixes but not for zeroing in on problem areas. You'll need a sophisticated equalizer to kill these peaks, whether it's built into your receiver or in a processor that you mount in your dash or near your amplifiers.
An outboard equalizer gives you multiple points for adjusting frequency response, so you can iron out the peaks in your system. A parametric equalizer allows you to vary the centerpoint and width of each EQ band, so you can really zero in on a problem area. Sound processors can help you eliminate frequency response peaks and increase bass response, and some even include a microphone for analyzing your car's acoustics.
This post is excerpted from a recent article in our Learning Center, Jeff's Tips for Getting Maximum Sound Quality in Your Car.
by Crutchfield's
Meet Jim Richardson
Why do we write? So you can find gear that makes you jump and shout.
I edit the home A/V and pro audio articles on Crutchfield.com. It's a cool gig for a guy who's been seriously into audio since way before 1974.
I started buying records, guitars, and gear with the money I made mowing lawns and delivering newspapers. Now the way I earn my money has changed for the better, but where it goes hasn't changed too much.
I was employee #007 when I started at Crutchfield back in 1976. Seriously, I was the seventh person Bill Crutchfield hired. Back then we all did a bit of everything. I spent time answering customer calls, packing boxes for shipment, purchasing merchandise, and writing catalog pages.
I left Crutchfield in 1983 to finish college. Then I worked as a newspaper reporter and editor before returning to Crutchfield in 1993.
I returned just in time to participate in the launch of Crutchfield.com, the first big ecommerce site in consumer electronics. Having a hand in that process was a thrill and an honor. And just look at how much we've grown since then. It blows old 007's mind.
About Jim
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