Car Audio 101: The Difference in Car Amplifier Classes

Nothing compares to the thrill of cruising in a vehicle while blasting your favorite songs. This experience is far better when you invest in the right equipment like high-end subwoofers, speakers and amplifiers.
Getting the most out of your car’s audio system can be a bit of a challenge, though. This is especially tricky when you’re unaware of what exactly goes into powering your setup. With confusing technical specs such as watts, frequencies, and low-pass crossover to contend with, it’s easy to get discouraged.
One specific area you can benefit from learning about? The many different amplifier classes. Keep reading to find out what these classes are and why they are so important when it comes to shopping for the right car stereo subwoofers and amps.

What Are the Amplifier Classes? How Are They Different?

Car audio amplifiers come in four classes: A, B, AB, and D. Each class has its own benefits and drawbacks based on how they are hooked up and how much power they use.
If you have no idea how these classes function, you’re far from alone. But don’t be discouraged because they’re not as complicated as they seem. Let’s take a look at how each class works, as well as the ensuing impact on sound quality and energy efficiency.

Class A

Think of Class A amplifiers as “always on.” Even when there is no input signal, a class A amplifier runs at full power. It sounds wasteful, but unfortunately, that waste is what gives it the best possible sound.
Since there is no process in which the amplifier is turned on and then off, there is no chance for distortion. The waste associated with Class A amps is mostly dispersed as heat. As a byproduct of this, Class A amps are large in size to accommodate the airflow needed to keep them relatively cool.

Class B

Producing less heat at a smaller size, Class B amps operate in a slightly different way than their Class A counterparts. Class B amps use two transistors instead of one. It makes them more efficient but also more prone to noise distortion, as the two transistors can be switched off when no input signal is needed.
There’s definitely a need for compromise with Class B amps. However, some consumers don’t mind the loss of audio fidelity if it means making the most of a smaller, more efficient amp.

Class AB

A solid compromise between power and efficiency, Class AB amps are commonly used in car audio systems. They nearly match Class A sound fidelity while providing a clearer listening experience than Class B components.
Class AB amps are an estimated 60 percent more efficient than Class A, allowing them to be outfitted in smaller enclosures. Along with Class D amps, these are the most common amps available for purchase through the usual retail channels.

Class D

Completely different from the three classes highlighted above, Class D amps have become the popular new standard in the audio world. Designed with onboard circuitry that creates high-frequency pulses, Class D amps are incredibly efficient.
Nearly all of today’s most popular amplifiers and powered subwoofers are Class D in specification. While they may feature some distortion at higher sound frequencies, Class D amps are more than worth the very slight compromise thanks to their much more compact size and energy efficiency.

How Do I Choose the Right Amplifier Type?

No one type of amp is ideal in every situation. As you make this key decision, you’ll need to think about your budget, your preferences for sound quality, and your preferred level of energy efficiency.
Many people prefer class D amps due to their many benefits and limited downsides. While there are definitely some solid AB choices available, the market is quickly shying away from these in favor of Class D. As such, if you wait long enough to buy, you may not have a choice in the matter.
No matter which type of amplifier you choose, you’ll want to protect it with a car audio extended warranty. Upsie provides options that cut out the middle man, giving you both tremendous savings and peace of mind. The right warranty will safeguard you against a variety of common problems that strike even the best amplifiers and subwoofers.
You can look at several solutions to get your amplifier fixed if it suffers damage, including convenient, local repairs. You’ll enjoy driving in your beloved vehicle a lot more when you know that your high-end sound equipment is properly protected with an extended warranty.

Learn More About Car Audio:

Return to all posts

* This article is over 6 months old and may or may not be updated.