Car Audio Equipment Terms

Most consumers specify what caliber of car audio performance they want when choosing an automobile.  But in order to really beef up the audio system of a used car or your new car's stock stereo, you need to familiarize yourself with a growing urban sub-culture fluent in some difficult jargon.

Don't be discouraged, though.  The original car audio system (called "stock") can serve as a template, on which you will may component speakers, amplifiers, and crossovers.  These terms are explained below with a handful of other important information.  It requires some literacy in sound processing, but with careful reading you'll make some educated decisions.  Otherwise, skip it entirely and write a big check to your nearest car audio installation center.

Head Unit This is the interface you use to control the stereo, sometimes just called the deck.  It is the tape deck, or radio or cd player.  Now they are made to accommodate all sorts of technologies like MP3, USB, WMA, and AAC.  Don't call it the stereo or you will be pegged for the greenhorn that you are.  Some specs to consider: 

 

RMS Power Output: This is the amount of power, in watts, that the amp produces.  A higher number means more noise, but not necessarily clear sound.

 

Preamp Outputs:   Refers to the presence of RCA output jacks in the back.  An important feature if you want to buy an external amp.

 

Preamp Voltage:   Power that the preamp is producing.  If you are buying an external amp, get 2 volts or more for the maximum output.

Speakers Or more precisely, component speakers.  Each set of car audio speakers should only produce sounds at their optimum frequency.

 

Tweeters: High frequency speakers that need to be directed at the listener. 

 

Midrange: You can guess what frequency these produce.  They are usually placed in the door panels or by the back windshield.

 

Woofers and Subwoofers:   Strictly reserved for the bass.  Budget for an amplifier, as these speakers require a little more power.

 

Design:  Refers to the number of drivers for your speakers.  One-way has a single driver and two-way will get you drivers for woofers and tweeters.  A four-way design has all three plus a second tweeter or midrange.

Amplifiers Simply enough, amps make electrical signals bigger before sending them to the speaker.  Any self-respecting audiophile will have an external amp in the custom car audio system. 

 

CEA-2006 Certified: Amps are measured in watts, and this agency ensures accurate readings.

 

Channels: Get a four-channel amp for the most options.  But if you only want it for your (sub)woofer, a single-channel amp with a class D design is built for low frequencies and will require less juice.

 

Speaker level inputs: If your stock head unit does not have preamp outputs, you'll need these to avoid buying extra stuff for hooking up speakers.

Crossovers These devices come in two varieties, active and passive.  Both parse out the frequencies to the proper speaker, but the active crossover does it before they reach the amplifier.  Actives are better because they prevent wasting energy that the amp uses in sending frequencies to the wrong speaker.  Of course they cost more and don't install as easily as the passive.

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