Adding a subwoofer to your car audio system will allow you to get that extra bass that will help enhance your listening experience. Often times without one, you could be missing out on a lot of that low-frequency sound in your music. Car subwoofers provide depth to the sound of your music by supplying accurate bass beats to supplement the high-frequency musical tunes. We carry car subs in a variety of shapes and sizes to suit your specific needs.

However, buying a subwoofer is a more complex process than picking one at random, throwing it in your car, and wiring it up. Some research is highly recommended so that you can choose the perfect subwoofer for your system. When choosing car subwoofers, you also need to keep in mind things like the amount of space in your vehicle’s cab or trunk and what kind of music you listen to. Most car audio enthusiasts take particular pride in their woofers.

When buying a subwoofer there are a couple of things you may want to consider before pulling that “Checkout” trigger. Read on!

Choosing The Right Subwoofer Size For Your System


Before you purchase a new subwoofer, it is important to note the physical size of the subwoofer you want. As with everything in car audio, space is not always readily available, and subwoofer sizes can vary from slim fit subs to 18″ behemoths. The size of your subwoofer (the diameter) is important to know for installation processes and if you are planning to purchase or build an enclosure. The most popular subwoofer sizes are 10″ and 12″. Other common subwoofer sizes are 6.5″, 8″, 13″, 15″, and 18″.

It is also critical for you to be aware of the mounting depth space you have to work with and the mounting depth of the subwoofer that you are planning on purchasing. If you buy a subwoofer that has a mounting depth greater than you have to work with, you’ll either have to get a different subwoofer or do some serious modifications.

Knowing What Type of Subwoofer You Need


The next thing you have to consider is whether you want an enclosed subwoofer or a component subwoofer. An enclosed subwoofer contains an internal amp. This makes this option much easier to install. This option also saves space and is easier to install as opposed to component subs. Component subs rely on an external amp to power them. These take up more space and can oftentimes be more costly. However, there is a noticeable difference in overall sound quality. This option is far more customizable to your needs. They are also more tedious to install because you have to build the enclosure and properly wire them.

What Are Voice Coils?

Subwoofer Voice Coils

A voice coil is the coil of wire attached to the cone. Driving a current through the voice coil produces a magnetic field, which in turn moves the cone. The number of voice coils allows for different wiring configurations. The type of voice coil setups includes single, dual, or quad voice coil. Dual voice coil subs have more wiring flexibility than single voice coil subs; however, single voice coil subwoofers provide easier hookup options for wiring multiple subwoofers in parallel or series. You may run a dual voice coil (DVC) sub in parallel, series, or combination. A quad voice coil has four voice coils and is equal to two dual voice coil subwoofers (in terms of wiring capabilities).

What Materials Are Used In A Subwoofer Cone?


Paper cones produce natural-sounding bass, but are the least durable cone material. This is why you commonly see materials such as polypropylene being used for cones. Polypropylene tends to be more durable than paper, but also retains some natural sound. Finally, you’ll find titanium cones and other materials in some premium woofers. This is all used for specific reasons depending on the manufacturer and can provide different-sounding bass.

Do I Need To Purchase An Enclosure?

Dual Subwoofer Enclosure

Component subwoofers should be mounted in an enclosure for optimal performance. You can choose a sealed, ported, bandpass, or truck & shallow-mount box based on your subwoofer specifications and available vehicle space. We also offer premade package deals under Subwoofers with Enclosures. These Enclosed Subwoofer Systems include subwoofers prebuilt into a box.

If space is at a premium, consider installing a powered subwoofer, which is essentially an enclosure loaded with an amplifier and a woofer. We also offer vehicle-specific subs that are specially designed to save space and match the interior of your vehicle.

Is Getting A Big Subwoofer Better?

MTX subwoofers

In the case of car subwoofers, bigger is not necessarily better. The best subwoofers have high sensitivity ratings. These measures how effectively a speaker converts power into sound. Subs with a higher sensitivity rating will play louder, given a set amount of input power.

To demonstrate, consider the following example. If “SUBWOOFER A” has a relatively lower power rating than “SUBWOOFER B”, but “SUBWOOFER A” has a relatively higher sensitivity rating, then “SUBWOOFER A” will play louder (assuming the sensitivity differences are substantial). Therefore, a smaller subwoofer with higher sensitivity ratings can boom louder than a larger subwoofer with lower sensitivity.

Taking Power Into Consideration

Peak vs RMS Power Rating

The RMS power handling rating refers to the amount of power a car subwoofer can handle on a continuous basis. Pairing your amps and subs with incorrect RMS power ratings could cause harm to the amplifier or subwoofer. It is ideal to match the combined total RMS wattage of the subwoofers to the amplifier.

We recommend slightly over-powering your subwoofer based on its recommended RMS power rating. This will help prevent accidentally over-powering or blowing your sub. You should select a subwoofer based on the amount of power output generated by your amplifier, the sub’s impedance, and the voice coil specifications.

For ease and convenience in finding the right amplifier for your subwoofers, check out AmpliFinder: An Amplifier Finder Tool designed and tested by Sonic Electronix. Just select your subwoofer’s manufacturer, model number, and how many subs you’ve got, and wait to discover the best amp that matches your setup. 

Series vs. Parallel Wiring

Assembling subwoofer and amplifier car audio

Another thing you have to consider is series vs parallel wiring. Subwoofers come in SVC (Single Voice Coil) which means it has two wiring terminal posts: one positive and one negative. 

There are two ways of connecting these two terminal posts to the amplifier through Series and Parallel wiring to properly manage the overall impedance load. 

Wiring in Series will double the impedance load and reduces RMS power.

  • Example: If we wire two 4-ohm voice coils together in series the total impedance will now be 8 ohms

Wiring in Parallel cuts the impedance load in half and increases RMS power.

  • Example: Two 4-ohm subs wired in parallel = 4 ohms/ 2 coils = 2-ohm impedance

Subwoofers also come in DVC (Dual Voice Coil), adding another pair to the positive and negative terminals to give more options in wiring the sub. 

The impedance measures the load value (in ohms) that the speakers present to the amplifier, or the amount of resistance to the current flow. Car subwoofer impedance can be rated at a 2 ohm, 4 ohm, or an 8 ohm load. When you are trying to match up a subwoofer’s power rating with an amplifier, be sure the power ratings are estimated at the same ohm load.

To help you in setting up the connection routes for your two audio devices, check out our subwoofer wiring diagrams to show you the proper, exact way of connecting your subs to your amplifier.

At Sonic Electronix, we’ve got the X-factor in providing top-notch car audio products and installation services. Boost your bass with our selection of subwoofers, subwoofer boxes, bass packages, and subwoofer installation accessories. Our customer service and technical support teams are available to you five days a week, and we’re always happy to help!