What is a Car Amplifier?

What does a car amplifier do? Car stereo amplifier is a device that boosts electric signals coming from a CD player, radio, and other sources of sound, to power subwoofers and speakers. Since in-built amplifiers are usually relatively weak, the drivers who need a louder and deeper sound with profound bass install an additional digital car amplifier. High-quality models don’t cause sound distortion, ensure better sensitivity and response.

Types of Car Amplifiers

Typically, amplifiers are divided into four major classes:

  • Class A devices ensure low distortion of sound and a high output, but they are huge and emit much heat because they are always on. It’s a versatile variant, but can be unsuitable for some cars.
  • Class B amplifiers are smaller and produce much less heat (they are automatically switched off when there’s no signal coming), though they can potentially distort signals and have a low audio fidelity. They are perfect for car applications.
  • Class AB is the golden middle of the above-mentioned variants, that’s why they are most commonly used in car audio systems. Although there’s always current going through the device, its power is adjusted accordingly.
  • Class D is often considered to be the best car audio amplifier because they quickly switch current on and off and ensure excellent performance. Although many mono subwoofers use amplifiers of this class, they are also suitable for full-range speakers.

Compare the Best Car Amplifiers




Power Output






Mode of functioning

Skar Audio RP-75.4AB

BUY NOW AMAZON 560 W AB 75 Watts x 4 Channels 7 x 19.5 x 3 inches 2 years 7.3 pounds

Variable sounding: features low pass filters and bass boost

BOSS Audio R110M Riot

BUY NOW AMAZON 1100 W AB 2 Ohm x 1 Channel 10.4 x 9.1 x 2.3 inches 6 years

4.4 pounds

Variable: low pass crossover and bass boost

Rockford Fosgate R500X1D Prime

BUY NOW AMAZON 500 W D 500 Wt x 1 Channel 10.5 x 11.8 x 4.2 inches 1 Year 5.35 pounds Low pass control & punch level control – perfect for low and bass sounding

Planet Audio AC600.2 Anarchy



4 Ohm x 1 Channels  or 2 Ohm x 2 channels

7.5 x 10 x 2.4 inches

6 years 5 pounds Variable low pass crossover, fixed high pass crossover, and bass boost

Alpine MRV-F300 4-Channel Car Amplifier

BUY NOW AMAZON 50 W D 4 Channels x 2 Ohm or 4 Ohm 13 x 9.1 x 4.3 inches Not specified 5 pounds Both low & high sounding

Pioneer GM-D8604 Class

BUY NOW AMAZON 1200 W FD 4 Channels

4.9 x 13.3 x 11 inches

2 years 6.5 pounds Both low & high sounding

Hifonics ZRX2416.1D Zeus

   BUY NOW AMAZON 2400 Wt D 1 Channel x 4-1 Ohms

17.3 x 10 x 2.4 inches

1 Year 10.71 pounds All modes would be perfect for low frequencies

JL Audio JX1000/1D 1000 Watt RMS Monoblock Class D Car Amplifier

  BUY NOW AMAZON  1000 Wt D 2 Channels x 2 Ohms 14 x 9.5 x 4 in 2 years (via authorized retailer only) 4.41 pounds Mostly high sounding

Kenwood KAC-9106D 2000W Monoblock Class D Car Audio Power Amplifier

  BUY NOW AMAZON  1000 Wt D One 1000 watts channel x 2 Ohms, or one 500 watt channel at 4 Ohms 15.3 x 4.8 x 10.2 inches 1 year 7 pounds Variable sounding: features low pass filters and bass boost

BOSS Audio R3400D – Riot 3400 Watt

  BUY NOW AMAZON  3400 Wt D One 1, 2, 4 Ohm Channel x 638/1700/3400 Wt

13.5 x 10.4 x 2.3 in

6 years 7.6 pounds Variable low pass crossover, fixed high pass crossover, and bass boost

What Should Be Considered When You Make a Purchase?

There are a few aspects that matter for the choice of a car amplifier.


As a rule, a car audio amplifier is installed in the trunk, so the choice should depend on how much free space you can dedicate for the device. If the sound system takes a lot of space, you can choose a compact model. Please, note that if an amp is stored in a confined space, it may cause overheating.

Number Of Channels

Usually, most car amplifiers have one channel. However, if you have several subwoofers, you can find a device with two or even four channels: it will make the sound deeper and richer. With several channels, one amplifier can work with several speakers.


The higher the power is, the stronger the sound gets. If you need enormous bass boosting, select models with over 1000 Wt output – they will make sound waves bump your car. If you need to make the sound a bit louder and deeper, a usual 250 Wt car audio amplifier will be enough.


Please, note that the sensitivity and volume control are not one and the same thing! Adjusting input sensitivity you can match the input and output signals to balance them and ensure maximum output potential with minimal sound distortion. An audio system with good sensitivity settings is loud, dynamic, and free from distortion.
It’s recommended to set the source’s output to the potential of 75%: that allows reaching the most optimal sound quality without damaging the device.


All car amplifiers are installed by one scheme, but some have installation instruments included in the kit, and others – don’t. Make sure that the wires and connections are already included because finding suitable accessories will be challenging.

How We Chose Car Amplifiers

To compile this list, we read every car amplifier review thoroughly and found the best 5 channel car amplifier models plus two more worthy models. The devices were connected to car audio systems of different vehicles: we analyzed the quality of sound, consumed power, distortion, impedance, and compatibility with car models. Users’ feedback was also taken into consideration.

Top-10 Car Amplifiers 2018

Find the best amplifier for car: here we review reliable and efficient models from different manufacturers. They are suitable for different car models – your choice should be based on the power of your car audio system, type of music you listen to, and your budget. On our car amplifier brands list, you will surely find something suitable.

Skar 4-channel amplifier

Skar Audio RP-75.4AB Full-Range MOSFET Class A/B 4 Channel Amplifier, 560W

This is a pretty efficient and reliable amplifier that comes with rapid misfit power supply and 4-level protection, even if it performs at its maximum. The model is versatile as it allows adjusting multiple variables (hpf, gain, bass eq, lpf, crossover and other features). Since it’s an AB class car subwoofer amplifier, it’s designed to produce a clean and high-quality sound without much power consumption and distortion. It operates through 4 channels with 4 Ohm impedance outperforming some models of the same price range and would be perfect for listening to music at medium loudness.


  • 4-channel amp;
  • AB class – a trade-off between power consumed and quality of sound.


  • needs efficient fans to prevent overheating;
  • filters aren’t good enough for some users.
BOSS 1100 Wt car amplifier

BOSS Audio R110M Riot 1100 Watt, 2/4 Ohm Stable Class A/B

Boss car amplifier is compact and low-cost, but very productive: maximum output of 1100 W allows getting maximum of your vehicle’s audio set without a hitch. It’s capable of both high and low outputs and produces a wide range of sound frequencies while boosting bass by up to 18db. This best cheap amplifier car also comes with a remote control for better user experience. Thanks to special transistors, a user can easily switch conduction modes and get the optimal level of output. Besides, it also features automatic shut-off protection in case the amp gets too hot. This is a model with a truly superior price/quality ratio.


  • produces a wide range of sound frequencies;
  • non-expensive and compact;
  • has the automatic shut-off for better protection;
  • has a remote control.


  • despite manufacturer’s promises, s prove that it’s better for low output;
  • distorts sound at high output.

Rockford Fosgate R500X1D Prime 1-Channel Class D Amplifier


A top-rated mono amplifier for car, Rockford Fosgate R500X1D is a reliable and powerful model. It comes with protection against short circuit and over-current, can be muted, has a MOSFET power charge, as well as phase switching and the thermal sensor. Besides, there’s a remote control, so if you’ve been searching for a Bluetooth car amplifier, it can be a nice alternative. Using the punch level control, users can adjust bass sounds to enjoy the perfect driving experience. Thanks to phase switching, you can get maximum of the subs and all other speakers reaching professional sounding.

Our opinion:

Although it’s a 1-channel amplifier, users rave about the quality of sound produced and its energy efficiency. If you don’t want to recharge the battery often, this is an optimal solution.


  • saves energy and automatically switches modes;
  • has a remote control;
  • comes with tools for installation;
  • high level of protection.


  • relatively expensive;
  • 1 channel only.
Planer Audio car amplifier

Planet Audio AC600.2 Anarchy 600 Watt, 2 Channel, 2/4 Ohm Stable Class A/B


Planet Audio car amplifier is another proof that a cheap and small amplifier can produce a heart-trembling bass. This AB-class model can power up a pair of 4 Ohm subwoofers, or two pairs of 2 Ohm subwoofers, which is enough for lovers of loud music. Sound modes can be easily customized: there’s a high pass crossover, bass boost, and low pass crossover. Thanks to bridge channels, it’s even more flexible.

Our opinion:

This is the best budget car amplifier so far because it produces a loud and clear sound while providing total freedom of customization: with the help of switchable input sensitivity control, a driver can achieve the balance between the quality of sound and the power consumed. 


  • 2-channel amp;
  • has a number of features for sound customization;
  • features the automatic shut-off;
  • comes with variable bass boost;
  • cheap.


  • overheats and shuts off quickly during hot weather;
  • some users complain that bass knob doesn’t work properly.
Alpine compact car amplifier

Alpine MRV-F300 4-Channel Car Amplifier, 50 Watts RMS x 4


Let not 50 Watt power outage confuse you – Alpine amplifier is a small device that concentrates power and energy. This is the best car amplifier for bass of D class, which is why users praise its energy efficiency and performance. The amp is enough to power 4 speakers with a higher power output (80-250 Watt). The model is compact and easy in installation thanks to advanced snap-on terminal covers and features 40% smaller chassis.

Our opinion:

Compact and strong, this device is recommended for cars with a small truck.


  • very powerful and efficient;
  • 4-channel;
  • compact;
  • maintains 2 Ohm and 4 Ohm speakers.


  • doesn’t have automatic shut-off, but overheats;
  • expensive.
Pioneer car amplifier

Pioneer GM-D8604 Class FD 4-Channel Bridgeable Amplifier Hifonics ZRX2416.1D


Pioneer car amplifier was created for advanced drivers and audiophiles who are ready to pay for what they want. Being an FD-class amplifier, this model produces both high and low sounds efficiently and clearly. Its versatile design allows for trouble-free installation, and the amp works well with 1-8 Ohm impedance speakers. Maximum 1200 W power outage over four channels is more than enough for filling any vehicle with ground-shaking bass and deep melodic sound.

Our opinion:

Pioneer is the best car amplifier in terms of quality and reliability – thousands of users prove that.


  • high maximum power outage;
  • 4-channel;
  • easy to install.


  • users complain that not all channels work.
Zeus Hifonics 2400 W car amplifier

Zeus Mono Class-D Subwoofer Amplifier, 2400-Watt


Zeus offers the best car stereo amplifier for lovers of aggressive bass and incredibly loud music. This model features a very low harmonic distortion and, being a D-class device, has a very well-thought design. Its sink is created for efficient heat dissipation, and surface-mount design makes it easy in installation. MOSFET power supply guarantees optimal power consumption. Besides, there are diagnostic light indicators, protection against overload and short circuits. All that is topped off by RCA outputs and inputs.

Our opinion:

It’s a must-have for users who value strong, clear sound and are ready to pay for quality.


  • very powerful and efficient;
  • well-thought design and simple installation;
  • protective features.


  • expensive;
  • 1 channel only.
JL Audio JX1000/1D 1000 Watt RMS Monoblock Class D Car Amplifier

JL Audio JX1000/1D 1000 Watt RMS Monoblock Class D Car Amplifier


One of the most top-rated models, JX Series Monoblock Amplifier can run in different modes and has a PWM switching power supply. The bass boost range is 0-12 dB at 45 Hz. The device has a smooth turn-on that prevents clicking when the system is switched on. According to reviews, it doesn’t overheat and is very strong despite its compact sizes.

Our opinion:

Compact and smart construction coupled with efficiency and reliability make this product worth every cent. It’s the best amplifier for car that boasts long service life and decent quality.


  • agreeable price;
  • compact size;
  • reliable and long-lasting.


  • this isn’t the best choice for bass amplifying.
Kenwood KAC-9106D 2000W Monoblock Class D Car Audio Power Amplifier

Kenwood KAC-9106D 2000W Monoblock Class D Car Audio Power Amplifier


If you want a non-expensive, compact Class D amplifier, pay attention to Kenwood’s KAC-9106D. It has two modes: one 1000 watts channel x 2 Ohms, or one 500 watt channel at 4 Ohms.  The device is great for amplifying bass and drums. Thanks to in-built subsonic filters, you can adjust the signal to get the clearest sound. On the opposite, 18 dB bass boost will flatten up the sound. This model has a signal sensing turn-on, so it can be combined with any kind of system. The aluminum cover will protect the connections and prevent mechanical damage.

Our opinion:

A versatile, non-expensive model for average users who need simple amplifying of sound. According to one car amplifier review, it has a mediocre quality, so professionals will definitely need a more advanced solution.


  • non-expensive;
  • easy in control;
  • compatible with all systems.


  • mediocre quality of amplifying;
  • requires batteries (bought separately).
BOSS Audio R3400D - Riot 3400 Watt

BOSS Audio R3400D – Riot 3400 Watt


One of the most efficient budget models, Boss Audio Riot R3400D is a class D amplifier that boosts bass sound making it bump user’s car. Sound customization is flexible: there are such options as bass boost, subsonic filter, low pass crossover. To top it off, there’s a remote subwoofer control option. There’s a strapping capability: two amplifiers can be used at 2 Ohms to get maximum performance. Variable input control allows for adjusting the sound properly. Automatic shut-off prevents overheating and saves energy.

Our opinion:

This digital car amplifier is recommended for drivers who need a non-expensive bass booster: it has all essential features.


  • cheap;
  • can be used with other amplifiers;
  • boasts a variety of features for maximum sound customization.


  • lasts for several months – many users report replacing it by warranty within 6 months.

Interesting Facts

The scheme of amplifier connection with car’s audio system

  1. To check whether you need an amplifier, turn off the music in your car with windows and doors fully closed. If there are distortion and lack of clarity, you need upgrading.
  2. Oxygen-free copper wires are the best for amplifiers, while Copper Clad Aluminum wires should be used carefully.
  3. Impedance (the resistance to the electrical current) is an important factor: the lower it is, the less distortion you’re likely to face.
  4. It’s crucial to use amplifiers corresponding with specifications of the original audio system. Strong amplifiers connected to low-power systems can easily burn.
  5. The best car amplifiers have THD (total harmonic distortion) up to 1%.

How to Use and Install a Car Amplifier?

In order to install an amplifier, you don’t need to visit a mechanic’s shop and pay huge sums for the service – it can be done manually. Just make sure that you buy an amp with a corresponding amount of supported channels and impedance. Some devices come with detailed instructions showing how to install a car amplifier, but if there’s no manual in your kit, videos and guides will help you.


Before you start, make sure that together with the amplifier, you get all necessary equipment and materials:

  • a gauge kit with different wires;
  • wire cutters or other tools for splitting;
  • suitable screws;
  • switch.

Some amplifiers already come with wires – that will save your time and ensure you have suitable components.

Connect to the battery

How to connect car amplifier? Security is a top priority: to prevent a shortcut, switch off the battery, and connect the positive wire to it. Secure the fuse to the battery leaving some space (up to 10-15 cm).

Wire the amp

After you’ve connected the positive wire, lead it to the amp and connect to the slot that says “+12”. Don’t forget to hide the wiring. Connect the short ground wire to the chassis near amp’s position. Wire’s other end should be connected to the GND amp’s slot. The blue wire is connected between “rem” slot and the car radio (wire colors should match).

Now put the fuse into the fuse holder to secure it. Put the negative power wire in its place: now the amp must be on when the radio is working. Now you need to wire the subwoofers and RCA cables to the amplifier. This way, you need to connect as many channels as the number of the speakers (subs).


Frequently Asked Questions

Q: How To Test A Car Amplifier With A Multimeter?

A: Connect the car stereo amplifier to speakers before the test. Use the voltmeter to set to AC voltage, turn the volume up on the control unit and check how the volt reading is rising. The meter will gauge the amount of power sent to subwoofers. Wait until the volt meter stops at the highest power for a few seconds – this will be the pear voltage measurement.
Once you get the peak voltage rating, type the number into a calculator and multiply the number by itself. Now divide this number by the subwoofer’s ohm load (it’s also called ‘impedance’). For example, if you multiplied 20 by 20, got 400, and have a 2 Ohm subwoofer, it would have 200 Watts of maximum peak power output. The RMS is about half of this number, which means your subwoofer can provide 100 Watts on a continual basis. For optimal performance, you should install subwoofers designed for 100 watts of RMS power.
Formulas are the following:
(AC Voltage x AC Voltage) / Impedance of the Subwoofer = Peak Power produced by the amplifier
Peak Power / 2 = RMS Power produced by the amplifier

Q: How To Bypass Protection Mode On Amp?

A: As a rule, the protection mode switches on without reason when there are technical issues with the amplifier. It can happen due to the following reasons:

  • Overheating;
  • incorrect amp installation;
  • wires get loose;
  • the amp fails internally.

To solve the problem, perform the troubleshooting processor or go to a service center to have the device diagnosed. Make sure that the car subwoofer amplifier is installed correctly, can be ventilated properly, and there are no mechanical and software failures.

Q: How To Wire A Car Amplifier And Subwoofers In Your House?

A: First, figure out the colors of wires that should be connected with your PC. Connect the amp to the power supply source to simulate Head-Unit starting. Use a sound system that has the same output as the subwoofer. As soon as all cables are connected, attach the rest. Now wire the sub to the amp, plug in the power supply in an outlet and switch the system on.

Q: How To Connect Car Amplifier To Speakers?

A: Run wires between the amp and speakers (should be on one side with the RCA cables, but power and speakers wires should be on different sides). Use appropriate connectors to wire speakers to your car audio amplifier (negative – to negative, positive – to positive). The larger terminal is the positive, smaller – the negative. If your speakers were powered by the head unit, you should disconnect them first. You should not connect both head unit and amp to speakers – it will damage the devices.

Q: Difference Between An Amplifier And A Car Stereo?

A: While an amplifier is a versatile device that can be used at home, too, a car stereo is made specifically for cars. Stereo is a device that allows controlling the entire sound system, while amplifier only provides a loud sound.

Q: Can Car Amp Drain Battery?

A: If there are problems with the regular power supply, the car amp will get energy from the battery. It also happens when subwoofers and the amp don’t match by power input and output.

Q: Why Do Car Amplifiers Overheat?

A: It happens when the device is used on 75%+ output mode, so there’s maximum power supply on a constant basis. Besides, it can overheat when being stored in a confined space without ventilation.

Q: Will Car Amp Work Without Fuse?

A: Yes, but fuse protects wiring better and prevents loss of wire connection when a car makes abrupt turns and moves. This is one of the most important parts of car subwoofer amplifier wiring.

Our Recommendations

We’ve tested seven top-rated car audio amplifiers and concluded that there are two models truly worth your attention: a budget BOSS amplifier that can power up four channels and ensure excellent sound without much distortion, and Alpine amplifier that combines efficiency with safety and clarity of deep bass sound.

The choice depends on your own preferences and requirements: some users can go with a low-budget device. Boss Audio Riot R3400D and PlanetAudio AC600.2 are both affordable (cost under $100), and make up for great sound.

If you have an extra $100-150, a D-class amplifier would be worth all spending. That’s the most energy-efficient solution so far and allows for easy customization. Although it’s quite expensive ($170+), Hifonics ZRX2416.1D Zeus is the best amplifier for car that will definitely provide a user with a clear and strong sound.

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