If you truly love good music, we are pretty sure that you will want to invest in a complete audio system. A subwoofer is a critical component in any audio system specially designed to reproduces the low frequency sounds formally referred to as bass. However, when shopping for a car subwoofer, you might be tasked to make a decision on what to choose between an enclosed and free-air setup for your car.
While enclosed subwoofers always deliver clearest and most resonant bass frequencies, most audiophiles today prefer free-air subwoofers precisely because they do not require a lot of space. Free air subwoofers are technically designed to operate without an enclosure, and they can be installed on door panels, rear deck, in the trunk, or even in a boat. The best free air subwoofer delivers excellent bass response when paired with a good amplifier while keeping the space in your trunk free for other stuff.
When mounting your free air subwoofer, one thing to remember is always to utilize sound deadening material to help improve the bass performance. With that in mind, read on to discover more on free air subwoofer pros and cons, as well as the individual reviews of top-rated free air subwoofers.
A Quick Comparison Table
1. Rockville RockGhost Hidden Powered 8″ Car Subwoofer
Rockville RockGhost is a hidden subwoofer, but it produces some of the cleanest and consistent lows you’ve ever heard. The sub really rocks, and you can control the bass from crisp to low to banging and a bass-thumping addition even in traffic. Furthermore, if your car already lacks space, this model can go inside the spare wheel beneath the cargo compartment, and best yet, the actual purpose of this subwoofer will leave you satisfied than ever.
Other key features and benefits of Rockville RockGhost
- Spare wheel subwoofer: This free air subwoofer fits inside the spare tire seamlessly, but the best way is to leave it on top of the spare wheel so that the spare wheel remains in place. This means that the sub will not take up your trunk space, plus it is a complete package. You can also mount your unit in the trunk or under the seat, but the best place is to mount it in the spare tire.
- Super clean sound: This 8″ powered sub delivers a superb sound that is super clean and one that does not fatigue your ears. The sound is musical and transmits evenly throughout the space without generating vibrations or unwanted sounds. This sub sounds cleaner and better than a regular sub placed in the trunk, and for the price and included wiring and parts, this is one of the best free air subwoofers you’ll find.
- Tunnel air-port design: Another key feature is the air-ported design that takes the sound a step further than other ordinary subwoofers. We also liked the wired 20-foot dash remote that offers adjustable gain, bass boost, phase control, and low pass crossover filter. Again, the sub boasts of a PWM MOSFET power supply and built-in amplifier, meaning it will play efficiently and cleanly even under high temperatures.
- Flexible rubber surrounds: Other than the above features, the Rockville RockGhost comes with flexible rubber surrounds that enables it to withstand its strenuous job of producing bass. Additionally, the rubber surrounds lasts longer, and they do not invert at higher excursion levels. Equally important, it is loud enough to vibrate your windows, and it does a great job of filling in the missing lows that you don’t get from a component setup.
- No additional space is required
- Easy to install and should fit in any vehicle
- It packs more power than expected
- The bass is deep and tight
- Compact sub, great sound
- The sub can get pretty hot when played loud for long
- There are reports of defects being shipped, but this gets resolved without a hitch
Rockville RockGhost is a great sub for the money, and it is an ideal choice for audiophiles who love to have a nice blend of sound. So, if you have a factory stereo or aftermarket stereo and looking for a unit that does not rattle the contents in surrounding vehicles or houses, this is the sub to go for.
2. Skar Audio EVL-12 D4
This subwoofer is made from high-quality materials, and it has impressive sound quality. It can keep up really well with a variety of music, including hip hop, jazz, and other music genres, without any issues. All you need to do is give it tons of power, and you will be amazed. You can pair this beast with a Monoblock amp, and when everything is tuned, this subwoofer really bangs.
Other highlights include;
- High roll foam surround: Skar Audio EVL-12 D4 comes with a high-duty high roll foam surround that enables it to play low tones effortlessly. The construction also includes a high-temperature 3-inch voice coil to ensure that the sub can be pushed at the highest levels for hours on end. The 25 Hz – 250 Hz frequency range ensures that the sub can move some air, and once you get the right amplifier, you will enjoy the bang.
- Powerful and efficient design: The EVL-12 D4 is rated at 2500 watts peak power with an advanced motor structure responsible for the head-turning bass. The lows are more present, and vibrations are reduced significantly. Moreover, Skar subs are unique and in a class of their own, so you will be beyond satisfied with this EVL series.
- Incredible features: Some of the features that make this sub the indisputable choice include the EVL’s signature two-layer red spider that connects to the coil using high-quality lead wires. It also features an advanced air-flow cooling system that keeps the sub operating cool under extreme conditions. Furthermore, the 7.75″ mounting depth ensures ease of installation while allowing you to have multiple mounting positions.
- Build to play all day long: This unit is a dual 4-ohm subwoofer whose engineering gives a new definition to low-end sound reproduction. The construction and sound quality is simply amazing, and it is designed to play accurate and powerful sound all day long. That’s not all! This sub can take tons of power, and once everything is installed and tuned, this sub really bangs.
- The sound is unbeatable for the price range
- Clean bass
- Great sound at first, even better once broken in
- The sub can handle some power
- Quality sound and construction
- Some audiophiles feel it is not loud enough
- Relatively low sensitivity
This Skar Audio, 12-inch subwoofer, is compact but very powerful. It hits very hard and low as long as you use it with the recommended amplifier. The sub is efficient and delivers sufficient power without draining your car, so if you are having trouble deciding what car subwoofer to buy, look no further.
3. Rockford Fosgate P2D2-12 Punch P2
Rockford Fosgate Punch series of subwoofers never disappoints, and the P2D2-12 is a showcase of their commitment to sonic excellence. This P2 subwoofer is engineered to deliver that powerful low end that you can feel and always stand out in a crowd. It is also very dependable, and you can put it through countless hours of heart-throbbing bass without signs of wearing or anything.
- Impactful bass: Rockford Fosgate engineered the P2D2-12 to produce the kind of powerful bass you always crave during your trips. Its paper cone is reinforced with Kevlar fiber to give a bass impact you can feel and one that is warm and exceptionally hard-hitting. The design of the paper cone also features a high-density poly- foam surround that helps increase the radiating cone area by 25%, enabling it to put out even more bass.
- Made for long woofer life: This P2 sub features the company’s proprietary spider plateau venting construction to offer a cooling effect to the voice coil and to increase the woofer life. Equally important, the extended pole and backplate give more room for the heavy-duty excursion so that sub can hit those deep lows without much distortion. Furthermore, its power handling conforms to CEA-2031 industry standards, and as such, it can handle power under continuous demand.
- Flex fit basket: The sub uses a flex fit basket design, which utilizes slots instead of the ordinary single screw sized holes for mounting the speaker. This means you can always make slight adjustments when it is mounted for a more custom fit. An optional grille is also included, and a diamond cut cast aluminum trim ring to provide more strength while minimizing weight.
- Robust design: This P2 subwoofer is incredibly lightweight yet very rigid thanks to the stitched wire technique that significantly reduce the mass of the tinsel leads. This helps to spread the strain and stress over a wider area. Consequently, this helps to improve the performance and reliability of the subwoofer significantly. Additionally, the tinsel leads are designed to handle extreme duty cycles and fatigue, contributing to the robust design.
- It definitely packs a punch
- Great budget sub
- The sound quality is amazing
- The sub hits good and clean, no distortion
- Awesome look that you’ll want to show off
- Low RMS
- Pretty good sound, but a little more bass could be better
You can never go wrong with a Rockford Fosgate subwoofer. The sub has multiple compliments about how crisp and clear this subwoofer sounds, not forgetting about the punch. Once paired with the right amp, it will leave you way more impressed than you thought, considering it has a low RMS.
4. Kicker CompRT 43CWRT82
Kicker CompRT 43CWRT82outperforms and holds up like no other sub in this category, and it offers a lot of kick for such a small unit. Generally, the results are amazing, and it is one of the best free air subwoofers if you have a small amount of space to work with. The construction feels solid, looks good, and it will, without doubt, sound good.
More about Kicker CompRT 43CWRT82
- All-weather thin subwoofer: CompRT 43CWRT82 comes in a low profile, and the company designed this sub with compact cars, small trucks, and ATV’s needs in mind. It is a small sub but performs like any other full-sized subwoofer but without sacrificing all your trunk space. The mounting depth is less than 3 inches, so you can have multiple installation option.
- Built for booming bass: The sub features a solid Injection-molded polypropylene cone that will not flex or cause distortion even when cranking the volume. Additionally, its Santoprene rubber surround can withstand abuse and will last you through the years. Similarly, its double red stitching forms an exceptional bond between the cone and the surround for great performance even during extreme conditions.
- Compatible with many systems: The CompRT 43CWRT82 handles up to 600 watts peak power and 300 watts RMS, so it can work with many systems as long as you have a solid amplifier. Additionally, the dual voice coils give you multiple wiring options, and it will keep pounding as hard as you want regardless of the type of music.
- Custom SoloKonTM technology: The CompRT series, just like other Kicker’s series, uses their unique SoloKonTM technology to connect the cone to the vented back brace. This helps to cool down the motor and eliminate distortion for a smooth and clean bass. Similarly, its unique interior support system is designed to deliver ‘fat’ bass while keeping the design as thin as possible.
- Perfect fit for small cars
- Nice bass for the money
- It sounds really clean
- Thin mount
- The sound quality and construction is unbeatable
- Considerably low RMS power
- Some feel it would have been a little louder, but for the price, the performance is outstanding
If you’re looking for more bass in a tighter space, this small sub is a great, shallow woofer for both factory and aftermarket audio systems. The bass level rarely out powers your music, and you will be super happy with this purchase.
5. Pyle PLPW8D
If you are looking to add some serious heart-throbbing bass, the Pyle PLPW8D power series subwoofer has your audio solution. This rugged subwoofer adds quality enhancement to your sound system and gives life to your entertainment system. It is a quality product, and all you need is decent equipment and a good tune when you run it. So, whether you’re looking to customize your boat, car, or RV audio system, PLPW8D has everything you need.
- Unmatched performance: The Pyle PLPW8D is equipped with a 40 oz. magnet that enables the sub to produce powerful audio to enhance your car stereo. Also, it has SPL or sensitivity of 89dB to ensure perfect clarity and dual 4-Ohm impedance that you can wire as either 4 or 8 Ohm. Again, this 8-inch subwoofer is rated at 400 watts RMS and 800 watts maximum power for high sound resonance.
- Designed for durability: The PLPW8D comes with a specially treated foam surround for added durability. Moreover, it is entirely made of non-fatiguing suspension to keep other equipment safe. The subwoofer also boasts of black steel basket, non-pressed paper cone, and the 1.5″ 4-layer voice coil that is made to resist corrosion for enhanced life span.
- Shallow mounting depth: With a 3.7″ mounting depth, this sub is easy to install, and it will fit most audio systems for cars as well as most boats. Further, its diameter is 8.2 inches, and it comes with all the necessary cables, user manual, and the installation template. Besides, this subwoofer is equipped with spring loaded push down terminals that helps to maximize sound quality.
- Bumped and vented motor design: This superior motor design helps push your audio to the maximum while helping extend the subwoofer’s life. The sound is very clean, and its extra punch vastly outperforms other subwoofers in this category. However, they might not handle very high volume very well, but they will definitely give you that low-end sound you want.
- The bass is good, especially for its small size
- Greatly exceeds expectations
- SPL is impressive
- Decent overall construction
- Pretty light, good for most vehicle application in general
- Not muddy
- It is an entry-level sub
- It might not handle heavy low punches as expected, but the performance is still impressive
Pyle subwoofers are power horses, and this model is no exception. It is a driving force behind any great sound system, and it will provide you with the sound performance that has been missing in your audio setup.
6. Infinity Kappa 1200W 12″ Subwoofer
If you are looking for a more engaging audio experience when going for a ride, Infinity Kappa 1200 watts is a dependable sub. It excels in a variety of car applications, and it can equally be used at home. The sub handles plenty of power, so you can expect extreme output from this sub. Moreover, it is made using innovative materials and technology to provide accuracy and detail that will exceed your expectations.
- Selectable Smart Impedance (SSI): Most car audio systems are designed to handle either 2 or 4-ohm impedance. However, this Kappa series gives you the freedom to choose and configure your system exactly the way you want. Kappa’s SSI proprietary technology allows you to build a high power system by flipping a switch without complicated wiring. As such, if you are thinking of adding another sub or using more power, this feature will make it easy for you.
- Aero-cooling design: Other than the SSI feature, the sub comes with a unique aero cooling design that keeps its 2-inch voice coils cool. This design also helps to increase power handling capability while improving the reliability of the sub. However, most experts recommend you let the sub break in on low sensitivity for a while, after which you can turn it up; otherwise, you could blow your sub.
- Acoustically damped glass-fiber cone: This Kappa subwoofer has incorporated glass fibers on their cones to eliminate distortion to offer you nothing but pure bass. The glass fiber cones offer exceptional clarity and detail, and they make your music come through loud and clear. The bass is outstanding at all volumes, can hit all the notes, and the best thing is you don’t have to worry about wires.
- Improved performance and flexibility: For any subwoofer to function effectively, it requires power. The terminals on this subwoofer are designed to accommodate up to 8 gauge wire, and this means low-resistance and reduced loss of power to the sub. Besides, Kappa subwoofers are known for their bass performance, and they offer the versatility you need to build a customized system for your different needs.
- Accurate sound reproduction in any application
- The bass is smooth and accurate right out of the box
- Aesthetically pleasing
- Immersive experience; fantastic home theatre sound
- Solidly built
- It is not ideal for those who want chest-pounding bass
Infinity Kappa 1200W is an ideal choice if you are looking for sound quality over booming, not to mention it looks stunning. It definitely needs more power so you’ll need to keep this in mind when pairing with an amplifier. The selectable impedance is a great feature, especially when you decide to get a second sub.
7. JBL Stage810 (STAGE810AM)
First and foremost, the sound is incredible for an 8″ woofer, and it has been engineered to deliver high output and low distortion bass with maximum power handling of up to 800 watts. Additionally, JBL loudspeakers and subwoofers are tuned by some of the best transducer engineers to ensure that you get the best sound possible. In the box, you’ll get the subwoofer, one foam gasket, the owner’s manual, and two color brand stickers.
- High-grade materials: The polypropylene woofer cone and hi-roll rubber surround are designed to offer you a high-efficiency design regardless of your application. Further, JBL believes that quality should not always be expensive. This sub is quite affordable, but the materials used for construction are way worth more than the stated price. It is a good subwoofer, and you can be sure that everything was made right and that your investment is worthwhile.
- Super reliability: BL Stage 810, just like other JBL speakers, has been subjected to a rigid testing process that would otherwise break up lesser speakers. This subwoofer has undergone the Harman standard reliability testing that involves different procedures such as freezing, blasting with ultraviolet radiation, as well as driving them at full power for days to prove its reliability.
- Quality output: This JBL subwoofer offers exceptional output, and it adds value to your listening experience by making you love your music even more. Though it is not made to be loud, it has a clear note enhancer with zero distortion and disturbance. What’s more, clarity is enhanced, and every song you listen will feel like magic to your ears.
- High performance 800 watts subwoofer: Bass boost is enhanced in this subwoofer by its ability to utilize up to 800 watts in short bursts. This amount of power is sufficient in most cars and even in average rooms, so whether you are looking to replace your factory unit for your car, truck, or for home theatre, this is a perfect choice for you. Besides, the frequency response is up to 200 Hz, which is just right for all types of audio.
- Solid bass: no waffling, no distortion
- The sound quality is crisp and deep
- Easy to install
- Small yet powerful subwoofer
- Very reasonable price
- Good punch
- Not a boomer sub, but it sounds just good
- It might not fit some car modes; small adjustments may be required
The JBL Stage810 is of great quality, and you wouldn’t expect any less from JBL. It sounds great for its size, and it does not overpower stereo speakers. It is one of the best free air subwoofers for most applications, and it takes it like a champ and does what it is supposed to do.
Free air subwoofer vs. enclosed
Ideally, the choice between a free air and an enclosed one will be guided by many factors, which include but, not limited to the space available, your budget, type of car, among others. Also, your music preference is a key factor, and it will determine the type of subwoofer that is suitable for you. For instance, if your trunk space is usable, then an enclosed is a wrong choice. On the other hand, free air setups work best in applications with limited space like small cars or cars that don’t have a lot of space. Read more on differences between free air and enclosed subwoofers.
Can a regular subwoofer be used as a free-air sub?
You can use a regular subwoofer as a free air mount but it will not deliver the kind of bass performance you get when you use the same sub in an enclosure. When you decide to run a sub free air, both its efficiency and power handling goes down significantly.
This is because regular subs are designed to use air pressure inside the box to damp the motion of the cone. On the other hand, free air subs get their damping from suspension, and as such, most free air subs have a stiff suspension to maximize their efficiency.
Regular subs don’t have this design, so using them in free air setups put them at risk of over-excursion. For this reason, it is recommended to go with a subwoofer that is specifically designed for free air mounting.
Free air subwoofer installation tips
The idea of a free air subwoofer is to eliminate the complexity of enclosed setups by creating a great sounding bass without the added work of sealing the enclosure. The ease of installation and minimum modifications are an added advantage for the free air subwoofer users. However, most setups require you to put in place baffles to seal the trunk, even when using a free air sub.
It is important to note that a free air subwoofer does not require as much sound wave isolation as an enclosed subwoofer. Also, free air subs are less susceptible to distorted sounds, such as when you have things in the storage space that might interrupt the sound waves. However, you will still need to isolate the sound waves from interfering with your sound response.
If you decide to mount your sub on the rear deck, consider incorporating sound and vibration absorption materials to help reduce vibrations and rattles. Remember, a more rigid surface will help improve the subwoofer response.
Your setup can also greatly benefit from using a baffle board. The sealed surround will produce a better sounding system, especially when you plan to mount your sub at the back of your rear seats.
Undoubtedly, the best way to get full-sounding bass in your car is by adding a car subwoofer. The best part is that there plenty of good subwoofers that are specially designed for free air mounting. Installing the best free air subwoofer will deliver an excellent bass response provided that you power it with a sensible amplifier and insulate the car properly. While most free air subwoofers offer plenty of bass without sacrificing a lot of space, they do not deliver booming or tight bass like enclosed subs. So, if you have space and the budget, you may be better off considering using bigger subwoofers for superior sound quality.
Michael Evanchuk is a San Francisco-based sound engineer with 20 years’ experience installing, troubleshooting, and repairing commercial, automotive, and household sound equipment. Evanchuk owns an auto stereo center, where he offers highly competitive car audio installation and repair services. He has written dozens of articles on different sound engineering topics, all of which have been published in leading journals, blogs, and websites.