Car trunk with subwoofers, speakers and amps.

Definitive Car Subwoofer Buying Guide

Whether you listen to rock, rap, country, or jazz, there’s one stereo component you’ll want in your car’s audio system: a high-quality subwoofer. Why? You’ll have a richer listening experience, as a subwoofer adds definition to your music while complementing the high frequencies of your speakers. 

At Audio Legion, we sell a variety of subwoofers for cars, trucks, SUVs, and pretty much any vehicle you can imagine. To help you find the best one, we’ve created this convenient buying guide. Here, you’ll find everything you need to know about what a subwoofer is, how they work, and how to find the best one for your ride.

What is a subwoofer?

A subwoofer is a loudspeaker that’s used in conjunction with your vehicle’s existing speakers to produce higher-quality sound. They work by increasing low-pitched audio frequencies, which most of us know as bass. As a result, you hear clearer music with enhanced bass lines and drum beats that generic or factory speakers can’t typically produce.

What makes a good car subwoofer?

Not all subwoofers are created equal. Here are several features to consider when it comes to choosing a quality subwoofer.

Power (RMS ratings)

If you’ve researched subwoofers, you’ve likely seen a number with RMS behind it, which stands for root mean square. The RMS of a subwoofer indicates the amount of continuous power the speaker can produce. Some speakers have an RMS as low as 50 while others feature a 3,500 RMS. The higher the RMS, the more powerful the subwoofer. To determine the RMS of a subwoofer, multiply its wattage by 0.707. A 500 watt sub, for example, has 353.5 RMS (500 x 0.707 = 353.5).


Another feature of subwoofers is sensitivity. At a higher rating, the subwoofer doesn’t need as much power to produce sound, whereas a lower sensitivity rating requires more power.

Frequency range (how low a sub can play)

The frequency range indicates how low a subwoofer can play. A good subwoofer ranges anywhere from 20 to 200 Hz, also known as Hertz.

Number of voice coils 

A voice coil is attached to the tip of a subwoofer’s speaker cone. Subwoofers either have a single voice coil (SVC) or a dual voice coil (DVC). The only difference here is that a DVC subwoofer has two coils, meaning there’s an extra wire that provides more connection options to amplifiers.


In simplest terms, impedance is how much of a load the speaker will place on an amplifier. Most subwoofers have an impedance from one to four ohms. The lower the impedance, the harder the amplifier has to work.


The styling of a subwoofer is important, as you want it to match the aesthetics of your vehicle. Good subwoofers should look sharp and blend into your interior. You can even opt for a speaker that has an accent color to complement any bold features inside your car.

What kind of subwoofer do I need for my vehicle?

There are several ways you can approach choosing the best subwoofer for your car.  Here are some questions you can ask yourself to get started:

  • How much bass do you need?
  • How many subwoofers do you want?
  • How much power do you want them to have?
  • What audio system do you currently have?

Once you determine those answers, you can shop for your subwoofer using a few different approaches.

Shop by wattage

Shopping by wattage based on your current sound system is a simple way to shop for the right subwoofer. Here’s a quick guide based on what you have now:

  • If you have a factory radio: 50-200 watts
  • If you have an aftermarket receiver: 200-300 watts
  • If you have amplified speakers with about 50 watts per channel: 250-500 watts
  • If you have a system with 100 watts per channel: at least 1,000 watts

At Audio Legion, we have subwoofers ranging from 400 to 7,000 watts, giving you ample selection based on power.

Shop by enclosure type

Subwoofers must be placed in an enclosure to function correctly. Depending on where you want your speakers in your vehicle, it may be easier to choose the enclosure type first, before selecting the right type and size speaker. 

  • Sealed enclosures: Also called boxes, these are airtight and ideal for faster-paced music with bass, like pop, classical, and jazz music. Sealed boxes usually create more accurate bass reproduction than ported boxes, making them ideal for sound quality applications.
  • Ported box: These are best for hip-hop, heavy metal, or rock music. Ported boxes don’t generally require as much amplifier power as a sealed box. While ported boxes don’t reproduce bass frequencies as accurately as sealed boxes, they are louder, making them ideal for SPL (sound pressure level) applications.
  • Vehicle-specific enclosures: Depending on where you want your subwoofer placed in your car, you may want to browse vehicle-specific enclosures to ensure a proper fit before buying anything.

Shop by diameter

If you determine the type of enclosure you want first, shopping by diameter is the next best move. If you’d rather shop by other features first, here are some things you should determine beforehand: 

  • Number of speakers you want
  • Design of the enclosure
  • Level of sound pressure you want

Whether you want a single subwoofer in a small enclosure or a customized design with multiple speakers, Audio Legion has you covered with subwoofers ranging in size anywhere from 6.5” to 15” in diameter.

What about an amplifier and gauge wire?

If you want to place a subwoofer in your car, you’ll also need an amplifier to enhance the quality of sound. Be sure to choose an amplifier that provides the same amount of power (wattage) as your subwoofer, as you’ll get the most optimized performance if you match them. 

The size of your gauge wire depends on the power of your amplifier, as it needs to be able to handle its electrical current. At Audio Legion, we provide 0- to 16-gauge wires for your subwoofer and will help ensure you select the perfect size for your system.

Where should I place my subwoofer?

Subwoofers are most often installed in the back seat or trunk of a vehicle. Since they may take up a lot of room, though, you may opt for a more subtle approach where the subwoofers are installed into car doors or even the dashboard. But placing your subwoofer isn’t just a set-it-and-forget-it task; you also want to make sure it’s pointed in the right direction. Here’s are some helpful hints based on where you place it:

  • In the rear of your car: Point the subwoofer towards the trunk or hatch of the vehicle.
  • In the front of your car: Point the subwoofer towards the back seat.
  • In the trunk near the hatch: Place the subwoofer facing upward.

How do I install a subwoofer?

You can choose to install your subwoofer on your own or through a professional installer. If you opt for at-home installation, be sure to arm yourself with the right installation accessories beforehand. There are several resources out there, including instructional videos, to walk you through the process. If you’re unfamiliar with audio equipment or even a little unsure of how to install your subwoofer, seek a professional to install it for you.

Breaking in your subwoofer

If you install your subwoofer yourself, recheck your connections before firing it up. Once everything looks good, choose a song with a repetitive rhythm that has deep bass. Play that song on repeat at a moderate volume for about 15 minutes. After that, turn the volume up too high and play it for another two hours. For your final break-in, aim to run the subwoofer for 10 to 12 hours. Road trip, anyone?

Let Audio Legion help find the right sub for your car

For the ultimate and perfect subwoofer for your car, turn to Audio Legion. Our knowledge, expertise, and top-of-the-line subwoofers will provide the best music listening experience in your vehicle. Here’s a look at some of our powerful subwoofers to choose from:


  • S25 series: 6.5”, 8”, 10”, 12”. 15”; 400-1,600 watts
Ready to turn up the bass? Shop our car subwoofers today, or contact us for support. We’re ready to help you have the best music listening experience ever.