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What Does A Car Amplifier Do?

what does a car amplifier do

If you intend to install premium audio equipment into your car, an amplifier will be required. Although many stereos may have built-in amplifiers, they simply aren’t up to the job playing loud music whilst retaining the sound quality.

By installing one of the best rated car amplifiers on the market, you can provide your speakers with a clean source of power. This means you are able to get the most out of your speakers and retain or further improve the sound quality inside of your car.

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What Exactly Do They Do?

A common question asked by many people is “what does a car amplifier do?”. In short, they transform a small/weak audio signal into a more powerful one, which has the result of increasing the power to the speakers. The transformation is often referred to as “amplifying the signal”, which helps to reduce distoration.

Why Install an Amplifier?

The first reason to install an amplifier is that it allows you to play louder music without distortion. There is nothing worse than not being able to blast out music regardless to how good your speakers are. Installation of an amplifier improves the audio signal, which has the result of reducing the irritating distortion.

Installing a powerful car subwoofer is another popular modification that may also require an external subwoofer. The amplifier sends power to the subwoofer, which then provides the desirable deep bass. Depending upon your audio setup, there may already be an amplifier included within the subwoofer design.

The third and final reason to install an amplifier is to get the most out of your speakers. If you have just installed new speakers but are disappointed with the sound quality, the reason may be down to the audio signal that they are receiving. Replacing either the head unit or installing an external amplifier will instantly improve the sound quality.

Built-in Stereo Amplifiers

With an amplifier, you have a clean source of power that can be driven to your speakers without straining any of your equipment. Although some car stereos may have a built-in amplifier, they are mostly limited to 10 watts RMS output per channel.

This limitation prevents the stereo from being able to retain the quality of the music, especially at high volumes.

It is possible to purchase stereos with improved amplifiers but this usually comes with an inflated price tag. A more cost effective solution is to purchase a standalone external amplifier that only focuses upon amplifying the audio signal.


For those that aren’t bothered by small amounts of distortion, an amplifier isn’t essential. Upgrading your head unit or speakers to high quality examples may provide you with virtually distoration-free music. However, if you are someone that wants the ultimate audio setup, an amplifier is a must. Although an amplifier is relatively expensive, once you have experienced the superior sound quality, you won’t want to go back.

procarreviews author

Written By Dan

About the Author

Dan is an automotive journalist and owner of over 10 cars ranging from supercars, tuned cars, classics and your good old beater cars. He always likes to get his hands dirty with nut and bolt restorations or detailing sessions using the best products on the market.

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