When searching for your car’s audio capacitor, aspects such as polarity versus the working voltage become important considerations. Due to the audio requirements for your car, the best capacitor aligns to a perfect speaker, which will effectively utilize the voltage produced, for maximum performance.

In the market, you will stumble upon capacitors measuring both below and above 2 Farads – scroll down to see our list that goes all the way to 30 Farads!

Recommended Car Audio Capacitors

ImageCar Audio CapacitorCapacitanceSurge Voltage
Rockville RXC2D 2 Farad...
2 Farad Pick

$38.95 at Amazon
2 Farad24 V
Sound Storm C22 2 Farad Car...
2 Farad Runner

$31.33 at Amazon
2 Farad24 V
Rockville RXC4D 4 Farad...
4 Farad Pick

$44.95 at Amazon
4 Farad24 V
5.0 Farad Digital Power...
5 Farad Pick

$48.69 at Amazon
5 Farad20-24 V
Power Acoustik PCX-30F...
30 Farad Pick

$99.99 at Amazon
30 Farad24 V

Under 2 Farad Capacitors

Our Pick

Rockville RXC2D Car Audio Capacitor

If you need 2 Farad capacitor at a great price and features, Rockville RXC2D is the go-to option. Unlike the Soundquest, you will have an audible alert in the case of reverse polarity, meaning you will have a better monitoring criterion.

Secondly, the LED display provides a visible measure of the available voltage, in such a way that one can detect overloads. With an average ESR of <0.00195, this cap is able to provide a capacitance of 2 Farads which is adequate for any car audio system.

This rates it among the best capacitors when it comes to power surges and RMS that are quite demanding. In addition, the stylish outlook of this capacitor makes it a perfect inclusion for the car interior. However, just like other brands, it requires skillful handling especially for the terminals that are quite fragile.

Other customers have complained of a shorter lifespan, although these are issues you can handle through proper installation and handling.


Sound Storm C22 Audio Capacitor

This Sound Storm capacitor combines a stylish look with reliable performance, thanks to the aluminum casing and the low Equivalent series resistance (ESR).

As a matter of embracing digitalization, the display screen provides a platform to view most of the important processes and detect any malfunctions, reducing the likelihood of accidents or damaging the capacitor. The manufacturer has lowered the ESR to the extent of maximizing the current output that you get at the satin terminals.

On the same note, this cap also provides a 24V worth of power surge. This means that it can support any kind of RMS, without interfering with the quality of the initial sound, at that point when the circulating power from the battery gets down.

Also Great

Rockford RFC1 Audio Capacitor

For those who are in need of a 1-Farad capacitor, due to budget or any other reason, then Rockford RFC1 is a perfect choice.

The brass and platinum casings used makes it a durable yet presentable car accessory, which is further encouraged by the mounting components that come in the package. While other capacitors are vulnerable to stripping, the brass used Rockford eliminates this issue for you.

Even with the 1-Farad capacity, the inclusion of a low ESR ensures that this cap has adequate and reliable power for the sound system. In fact, it is among the few capacitors that filter the sound of the speakers to give a consistent and smooth sound.

However, as expected, the low capacity exhibited by these capacitors reduces the RMS compatibility, in terms of the number of speakers and their watt limits.

Also Great

Power Acoustik PC1.5F

As for this brand, they have focuses on making the user interface easy and reliable for all users. The mounting brackets and the terminals have labels to make it easy for you to install and use the capacitor.

In addition, this cap works in a range of 12-16 Volts, which makes it is suitable for many RMS requirements as well as car batteries. Due to the need of charging efficiency, Power Acoustic prides in a powerful resistor that guarantees the user and gadget safety and lifespan.

The display screen is clear and the details visible, with most of the users rating its display among the best. In terms of the power storage and retention, the ESR and development technologies used have improved its capacitance and retention to higher ranges than most of the above 2 Farads brands.

Of course, if yours is a high demanding audio system, then you might need a higher capacity gadget, to supplement the 1.5 Farad provided by this product.

Also Great

Planet Audio PCBLK2.0 Car Audio Capacitor

This is a hybrid brand that combines most of the technologies, yet it retails at a cheaper price. This product seems to solve the charging and power outflow issues, through the stabilizer and consistent power flow technologies, respectively.

In this case, you will have a more reliable power reserve since the capacitor charges slowly and at a consistent rate. On the other hand, the charging system comprises of copper wires, which have a Surface Flex jacket, before casing with the nickel plate.

These properties promote the power efficiency of this cap, due to the reduction in the tendency of the capacitor losing the stored power through the wires. On matters durability, the nickel and aluminum casing on this capacitor is inert to rust and corrosion, meaning that you can install it near windows.

There is also a 3 Farad capacitor option – Sound Storm C352

However, with all the other technologies in place, the display screen is not as perfect and users have to estimate some of the voltage readings, which brings in its biggest drawback. On the other hand, the low price of this cap makes it a worthy venture for your car audio system.

Over 2 Farad Capacitors

4 Farad Pick

Rockville RXC4D Car Capacitor

The Rockville RXC4D 4-Farad capacitor is a perfect match for a 4000 watts RMS. It has a working voltage in the range of 14-20V, with a surge voltage of 24V.

This means that it can comfortably suit the place of 1 and 2-farad capacitors, without requiring much of skillful installations. Another remarkable feature is the Voltage display, which comes in a bright red color, to supplement the digital approach of the entire capacitor.

The ERS allows for maintenance of the audio intensity, even when the stock alternator runs to over 1200 watts, with your battery down. Unlike other brands who are victims of losing the initial Farad capacity, customers have termed this brand as a true-3-Farad capacitor, even in the long term.

However, the terminals lack a cover, which increases its vulnerability to damage and loss of the stored energy. In addition, high RMS watts above 3,000 reduce the efficiency of this capacitor.

5 Farad Pick


With a voltage measurement accuracy of +/-0.1VDC, this 5-Farad capacitor is a suitable option, with additional features compared to our runner-up.

For instance, in an effort to help save the reserved energy, this capacitor is synchronized to “sleep” when the volume is low. In addition, the manufacturer has increased the capacitance and reduced the voltage variation, to ensure the power flow is consistent. Due to these advancements, buyers have recognized the smooth quality of sound associated.

The 20-24 volt surge maximizes the power outflow of this capacitance, which gets a further boost from the +/-5% capacitance tolerance ratings. In order to guarantee your safety and that of the capacitor, the audio warning for the low, high, and reverse polarity ensures you have an update on the gadget’s current conditions.

The digital display ensures you determine the voltage levels and make adjustments if need be. The biggest drawback is the loss of capacitance, with time, which could be because of consistent charging and discharging of the capacitor.

10 Farad Pick

Planet Audio PC10F

Well, if your car audio system records 10000W of RMS, then a 10-Farad capacitor should be the minimum installation. Planet Audio is a 10-F capacitor that combines the display technology with ERS, in an effort to promote the convenience of use and reliability based on the intended function.

For a capacitor with such a high Farad capacity, it is suitable for all manner of RMS requirements, making the capacitance and terminal voltage important. Due to the higher capacitance, it supports deep bass even at maximum volume, without interface on the sound quality or even power surges.

The blue LED display provides monitoring and evaluation platform for the cap’s parameters such as voltage and charging levels. However, some customers have complained of voltage drops, which could be resulted by inadequate charging, especially when the battery or the amp has power issues.

The other drawback is poor retention of stored power as well as unreliability especially when the battery suddenly goes down. Fortunately, one can solve these issues by properly charging the new capacitor.

30 Farad Pick

Power Acoustik PCX-30F Car Audio Capacitor

The Power Acoustik 30-Farad capacitor uniquely utilizes carbon foil type of technologies, to enhance the retention and outflow of the power reserves. With a 30-Farad capacity, it means that your car’s RMS should have a maximum of 30,000 watts, a factor that makes it suitable for heavy audio systems.

The Satin and Chrome finishes give you a stylish outlook while the voltage meter presents both the available voltages and the incidences of reverse polarity.

Since it deals with high voltages, it comes with a protection indicator that detects any issues that could be hazardous. The display is an LED accent configuration that promotes visibility and monitoring of the cap’s parameters.

The major con to expect is dimming of your headlights, especially during the initial installations, due to the high power surges required for this capacitor. Otherwise, it presents a perfect match for demanding RMS, due to the low ERS and high capacitance.

Car Audio Capacitor FAQ

What does a capacitor do for a car audio system?

A capacitor is a device that temporarily stores electrical energy, by filtering out any excess circuit voltages. In the case of car audio capacitors, the aim is to act as a reserve to feed your amplifiers and subwoofers, given that the power from the battery serves other purposes such as lighting and ignition.

How many Farads should I get?

Capacitors come in different sizes, depending on the capacitance measurements. On the other hand, different audio systems have varying power requirements, meaning that not all caps will suit your vehicle.

Each 1000W root means square (RMS) requires the 1-Farad unit of capacitance to detect and store the excess power in the circuit. Considering that, the caps act as a reserve, a 2 or 3-Farad capacitance will serve better since it will have stored more energy than the 1-Farad cap.

Will a capacitor drain my battery?

A capacitor won’t drain your battery. When fully charged, it will act as reserve power to your system.

How do I hook up a capacitor?

The first step is to determine the location, which should be closest to the amplifier to reduce the distance that the charge travels before reaching the capacitor.

Secondly, the location should be secure in such a way that the cap will be fastened with no chances of accidentally coming off. After defining this perfect location, the next step is to connect all the peripherals.

Whether you are using a distribution block or the cap’s multi-connectors, the positive terminal connects to the power lead while the negative goes to the chassis ground.

How to charge a car audio capacitor?

All new capacitors are discharged at the time of purchase, and you need to slowly charge it to full capacity. In case the cap you are using lacks the test light, a low resistance resistor will do.

In order to start charging, you just need to connect the resistor or test light to the amp’s fuse holder, then connect the battery’s ground cable.

Depending on the type of cap you are using, it will take a maximum of 30 minutes to fully charge.

You will observe the test light fading or the cooling of the resistor, as an indicator that you need to disconnect the charging resistor.

Image by rockvilleaudio.com

Vincent Talbot

Last update on 2020-09-30 / Affiliate links / Images from Amazon Product Advertising API