You can survive with just a regular set of speakers. You don't, strictly speaking, need a sub. But you cannot believe the difference having one will make. It's not just the inevitable boost to the low end that comes from a good quality sub; it's the overall richness of the sound. In this guide, we've evaluated the top subs for this year, no matter what your budget, or the size of your room. And to complete your system, check out our lists of the Best Floorstanding Speakers and Best Home Theater Systems.
Table of Contents
- Our Subwoofer Picks
- Subwoofer Comparison Table
- Subwoofer Buying Advice
Wattage: 220 (RMS)
Driver Size: 12"
What We Like: Clean and powerful bass matched with clever controls.
What We Don't: Lacks the ability to deliver huge, gut-punching bass.
It’s hard not to be wowed by the bass that comes out of the Q Acoustics Q B12. This subwoofer offers a polished sound that feels clean and elegant, while still delivering good levels of power. Despite having less than half the wattage of our former number one, the $800 ELAC Debut 2.0 SUB3030, the more affordable Q B12 sub genuinely impressed us with its outstanding and surprisingly subtle audio quality. We also found it a dream to use thanks to the intelligent rear-mounted controls. There’s even a magnetic metal plate that allows you to hide any connecting wires, while still letting you use the crossover and volume dials.
There’s one note of caution here, and it’s the power. 220 watts is nothing to sniff at, but compared to other subwoofers here, the Q B12 may come across as being a little underpowered. It delivers smooth, confident bass, but it doesn’t have the raw, stomach-pounding energy of subwoofers like $1,100 SVS SB-3000 or the aforementioned ELAC. If that’s your jam, then you may want to check out those models, and steer clear of the Q. It’s also huge: nearly twenty inches wide, and amazingly heavy at almost fifty pounds. That said, in our opinion this is a gem of a sub that offers stupendous sound at an affordable price. Hands down, this is our favorite subwoofer right now.
See the Q Acoustics Q B12
Wattage: 150 (RMS)
Driver Size: 12"
What We Like: Excellent sound quality for the price.
What We Don't: Such boring design they didn't even give it a name.
In the world of audio, there is no company that needs to have a corporate getaway more than Monoprice. There is absolutely nothing wrong with them that a few shared joints and some vigorous sex wouldn't cure. This is a company with such a deficit of imagination that they don't even bother to give some of their product names. This one is called the 9723.
But simply because a company has a boring identity doesn't mean they make boring gear. Monoprice have been massively successful, and one listen to this subwoofer will tell you why. It may not have the raw power of the ELAC Debut 2.0 SUB3030 or even the BIC America F12, but it delivers gorgeous sound quality, with huge, thumping energy but makes it sound a lot bigger than it is. And by stripping away all the design frivolities, Monoprice are able to offer this gem of a subwoofer for an absolutely knockdown price. If you are on a budget, this is the subwoofer you need to buy.
See the Monoprice 9723
Wattage: 800 (RMS)
Driver Size: 13"
What We Like: Builds on everything SVS does well.
What We Don't: Gloss finish picks up fingerprints, app needs some explanation.
The SB-3000 is the newest subwoofer model from the American legends at SVS, and we think it deserves to retain the crown of Best High-End Sub. As good as the previous model, the PB16-Ultra, was, it was also huge, ungainly, and way too much for most people. The SB-3000 dispenses with those issues, taking everything the Ultra did well and housing it in a much more compact, affordable frame. Those with overly large rooms may need two of them to get the best sound, but for 90% of people, one of these will blow the damn walls off.
One aspect we’d like to highlight is the excellent DSP (Digital Signal Processing). It allows a virtually infinite level of tweaking, and means that you can get precise, controlled bass that still manages to ooze power. This sub particularly excels with movies and television, giving gunfire, explosions, and punches real weight in the low-end. It’s another winner for SVS, and right now, the only question is where on earth they go from here...Read our full, in-depth review
See the SVS SB-3000
Wattage: 150 (RMS)
Driver Size: 12”
What We Like: Offers sound that is perfect for tight or small spaces.
What We Don’t: Dull looks.
If the BIC America F12 looked and sounded a little better, it would probably be at number one on this list, challenging the Q Acoustics model for top spot. As it is, it loses out to the Q B12 above it in both overall wattage and in sound quality. It has a slight dip in detail, and a lower RMS wattage than other models here.
However, it's still one of our top picks, which means it must have something going for it. That something is its unusual affinity for small rooms. It’s not especially small in and of itself, but we genuinely think it responds well to tight spaces in a way that other similarly priced subwoofers. The sound doesn’t have the same level of raw quality as other, more expensive models, but you still get a deep, extended and powerful bass effect. Although BIC America have a teeth-grindingly dull corporate identity - in common with many sub manufacturers, including Monoprice, below - they make some good stuff.
See the BIC America F12
Driver Size: Unknown
What We Like: Terrific sound quality.
What We Don’t: Requires that you get locked into the Sonos ecosystem.
The biggest black mark against the Sonos Sub is that you can't use it with equipment from other manufacturers. Got an existing home theater setup? You, my friend, are out of luck. The subwoofer only works with other Sonos equipment, and while the company makes a real effort to ensure that the setup process and ease-of-use works well, you might want to steer clear of this if that lock-in is going to be a problem.
The upside is that, if you're okay with using only Sonos gear, you'll be rewarded with some genuinely good sound quality. While the subwoofer is a little light on stats, it hardly matters: there's no need to set the crossover point when it's automatically tuned to all other speakers, guaranteeing you easy, clear, deep bass at all times (see our Buying Advice section, below, for more info on crossovers and how they work). We also really like the design, which allows you to put the subwoofer in just about any position – a boon for small spaces.
See the Sonos Sub
Wattage: 700 (RMS)
Driver Size: 12"
What We Like: Deep, rich bass.
What We Don't: Lacks modern features.
Above $1,000 is where you really start seeing subwoofers amp up the boom. With 700 watts of continuous power, Seaton Sound's amazing JS12 really brings the boom. It goes down to 20Hz – compare that to 28Hz for our leading sub, the Q Acoustics Q B12 – and you can really feel it. The audio has a rich, subsonic presence that will rattle your stomach and shake the walls. It's one hell of a thing to experience. For large rooms (over 250 square feet) this is easily the best option.
However, this is a subwoofer for purists. It offers almost no advanced features – no app control, no room correction. In addition, we think it may be a little bit too expensive for most people. However, if you like raw bass, and want some of the best in the business, then this is an excellent starting point. Seaton are a no-nonsense company from Chicago who've been making subwoofers forever, including the absolutely monstrous F18+, so you're in good hands here.
See the Seaton Sound JS12
Wattage: 1,920 (RMS)
Driver Size: 2 x 18"
What We Like: Huge power, fine-grained control.
What We Don't: Doesn't have the detail of other subwoofers.
With a frequency extension that goes all the way down to 16 Hz, the Power Sound Audio S3612 should be the first choice for anyone looking for the absolute deepest, darkest bass. While we prefer the Seaton Sound JS12 and SVS SB-3000 for detail, this is the subwoofer we'd go for if we wanted raw, unrestrained energy. You get an oddly-specific 1,920 watts of RMS power, making the S3612 the single most powerful subwoofer on this entire list. If you have a big room, and a bit of money to spend, you can tear reality apart.
While the Power Sound Audio S3612 does have a comprehensive set of physical controls, including room size selector, you should look at other models from the likes of SVS if you want high levels of digital control and DSP (Digital Signal Path) adjustments. Additionally, for all its power, the S3612 doesn’t quite have the finesse of other models, such as the ones mentioned above - particularly the SVS SB-3000. The Power Sound Audio S3612 is a sub designed for those who demand the absolute lowest bass. Only the Wilson Audio sub goes lower (10 Hz) and since that costs $25,000, we think your money is better spent with PSA.
See the Power Sound Audio S3612
Wattage: 350 (RMS)
Driver Size: 10”
What We Like: Weighty and realistic sound quality that excels with music.
What We Don’t: Unexciting design.
We test dozens of subwoofers at The Master Switch, and while it’s rare to find one that doesn’t perform well with music, we think that the RSL Speedwoofer 10S is the best we’ve heard. The punchy, weighty sound quality really lends itself to songs, with clear and realistic bass that brings out the detail in kick drums, toms, and bass guitars. It’s no slouch with movies either, but if that’s where you plan on using your sub woofer the most, we’d suggest going for something like the BIC America F12, which is actually a little less expensive. If, however, you plan on using your sub for tunes, then the RSL is unquestionably the best option. You can even make it wireless with an optional $50 module, making it a worthy competitor to the expensive Sonos Sub.
Outside of the slightly subpar performance with movies, there’s very little we don’t like about the RSL Speedwoofer 10S. We’d argue that the looks aren’t particularly exciting; we don’t have a high bar for subwoofers in this regard, we do like to see a little bit of flair, such as that found on the top-ranked Q Acoustics Q B12. However, look past that, and you’ll find a top rate subwoofer that beats the pants off just about anything else for music.
See the RSL Speedwoofer 10S
Wattage: 500 (RMS)
Driver Size: 12"
What We Like: Value and sound quality are second to none.
What We Don't: Won't satisfy those who like huge volume.
ELAC's super-impressive Debut 2.0 line includes a subwoofer that is easily in our top ten, regardless of room size. At 500 watts RMS and 1,000 peak (full breakdowns of those terms are in our Buying Advice, below), the SUB3030 delivers more than enough grunt, and the bass it puts out is solid and muscular. It satisfies whether you're watching movies, series, or playing games.
There are no physical controls. Instead, an Android and iOS app gives you access to all the functionality you need, including software that lets you fine-tune the sound to your listening environment. The sound isn't quite as deep or powerful as the SB-3000, above, but is more than rich and detailed enough for most people. ELAC have produced a genuinely brilliant product here, and at a very affordable price, although we will say that it's been beaten out by subs like the Q Acoustics Q B12.
See the ELAC Debut 2.0 SUB3030
Wattage: 150 (RMS)
Driver Size: 8”
What We Like: Revels in detail and realism.
What We Don’t: Underpowered, and a little too expensive.
The new PSB Alpha S8 replaces the Klipsch C-308ASWi on this list. It’s not only less expensive, but it offers even better detail and realism. We can think of very few subwoofers in this price range that deliver the kind of pinpoint, scintillating detail found on the Alpha S8, particularly when it comes to complex and nuanced instruments like double bass. It isn’t the most powerful subwoofer here, and that only 35 Hz of extension, the bass isn’t the deepest. But there’s a real sense that the audio has been hand tuned here, with the goal of maximum realism.
Unfortunately, that low-power does become a problem. Compared to similarly priced subwoofers like the Q Acoustics Q B12, the PSB Alpha S8 doesn’t quite measure up (220 watts versus 150). Partly this is to do with the unusually small driver; at eight inches, it doesn’t really have the grunt to compete with the big boys. We do love the attention to detail, but if you like your subwoofers loud and proud, you may want to look at other options like the aforementioned Q Acoustics model.
See the PSB Alpha S8
Wattage: 500 (RMS)
Driver Size: 12"
What We Like: Well-built, stylish, excellent bass.
What We Don't: Unusual driver/radiator design requires careful placement.
The Aperion Audio Bravus II 12D is quite an unusual subwoofer. It has a standard driver, positioned in the down-firing position (underneath the sub), coupled with two sideways-facing passive radiators. The result is effortless, clean, deep bass. The Bravus II 12D goes down to 19Hz, bested only by the Power Sound Audio S3611, which costs significantly more. We also love the looks – ours came in a gorgeous red finish that really stood out. If you like your subwoofer to look as good as it sounds, then the Aperion Audio Bravus II 12D is an easy choice.
However, the unusual driver/radiator design means that the Bravus II 12D needs a lot of effort to position properly. Although you should technically be able to position it as you would any other subwoofer, we found the positioning required a lot of fine tuning to get the best sound. The ELAC Debut 2.0 SUB3030, mentioned above, is not only cheaper, but is significantly easier to use. However, we still loved our Aperion Audio Bravus II 12D and believe it earned a spot on this list.
See the Aperion Audio Bravus II 12D
Wattage: 300 (RMS)
Driver Size: 10"
What We Like: A leap forward for Paradigm subwoofers.
What We Don't: Perhaps a touch expensive, although there are cheaper options available.
Paradigm's new Defiance range of subwoofers comes in several flavors. The X series deliver raw power, while the V series is all about affordability. They are all good, and offer several advancements on basic subwoofer design, but if we had to pick one, it would be this one. In our opinion, it offers the best combination of sound quality, features, and pricing, and will be the best choice for most people. While we still wouldn't pick it over the ELAC Debut 2.0 SUB3030, which we think offers better value for money, it remains a good alternative.
You also get an excellent range of features, including app control of the subwoofer, included Anthem Room Correction, and the ability to make the subwoofer wireless with the purchase of an additional module. The Defiance range is a forward-thinking series, and the X10 is its finest ambassador. Paradigm, by the way, recently came out with a new line of subs, including one that retails for (gulp) $7,500. We've heard it, and it's superb, but that price tag puts it way out of reach of most people.
See the Paradigm Defiance X10
Wattage: 300 (RMS)
Driver Size: 10"
What We Like: Sound has real energy and liveliness, updated input section.
What We Don't: Hideous cabinet design.
REL's new HT/1003 subwoofer marks a departure from the traditions of the company's founder, Richard Edward Lord. Until now, the late designer's subs received input from the stereo amp's speaker terminals. The HT/1003 has been updated to offer standard RCA and LFE inputs, which we seriously approve of. This makes the design more focussed, and more applicable to modern setups, including home theater rigs. This is an area where REL never felt quite at home before, but we think this improvement is a huge step in the right direction. It also helps that the HT/1003 sounds superb, with a great amount of thump and energy, especially while playing music. After tuning it to your room, its 300 watts of RMS power will shine in spectacular fashion.
One thing we didn't like, however, is the looks. This sub may be built like a tank, but compared to other REL subs - like the T-Zero, previously on this list - it just looks dull. A big black box with nothing special to recommend about it. There are a few nice touches, like upside-down labels on the rear end (for when you're bending over the sub to adjust something). But in our opinion, this is a product that looks best when the lights are off. If you're looking for a subtle design with not-so-subtle sound, the HT/1003 could be the subwoofer for you.
See the REL Acoustics HT/1003
Wattage: 500 (RMS)
Driver Size: 10"
What We Like: Excellent price and build quality.
What We Don't: Mid-bass isn’t as impactful as we’d like.
We finally had the chance to test the Monoprice Monolith M10-S subwoofer. It’s not quite as impressive as the REL Acoustics HT/1003, but it definitely deserves to be on this list. We think it provides a terrific amount of power and energy for the price – the 500 watts of RMS power is impressive. It’s also built like a tank, yet with a surprisingly subtle design.
It must be said that the sound quality isn’t quite to our standards. The sub-bass is fantastic, but anything above that feels just a bit weedy and undefined. You may need to spend time setting the crossover to extract the maximum amount of quality from the M10-S. Regardless of this issue, it definitely belongs on this list. If you want more power than the budget Monoprice 9723 can give you, then the bigger M10-S could be a very good option.
See the Monoprice Monolith M10-S
Wattage: 300 (RMS)
Driver Size: 12”
What We Like: Offers decent sound at a good price.
What We Don’t: Overrated.
There are plenty of websites that have talked up the PSW505 as one of the better subs out there, and we have no idea why. It's not that it isn't good. It's fine - delivering clear sound in a decent package. It's just that it's not nearly as impactful or as impressive as it's made out to be. For example, you could pay $20 less for a BIC America F12, and get a much better package, with far better value.
Again, we need to stress that the PSW505 only lacks in comparison. And perhaps, even saying it's lacking is a strong statement. It's just not quite as impressive as other models on this list. You still get a decent sub, with some nifty features (like an adjustable crossover), wrapped up in a moderately attractive housing, for not a large sum of money. If the BIC is a little hard to track down, then this is definitely something you should check out.
See the Polk PSW505
And For When You Win The Lottery
Driver Size: 2 x 15”
What We Like: Ridiculous sound quality.
What We Don't: Massive price tag, requires external amp.
When a Utah company, Wilson Audio, decided to create a subwoofer, they didn’t mess around. Their Thor’s Hammer has at least one thing in common with the actual Thor’s Hammer. It might not be able to summon thunder and lightning, and it won’t return to the place it was thrown from (mostly because it would take three men and a specialized catapult to actually throw it), but only those who are worthy may hold it. And by worthy, we mean loaded. This unbelievable subwoofer costs $25,000.
Here at The Master Switch, we don’t usually like talking about frequency ranges. We firmly believe that, when it comes to buying audio gear, they are nearly useless in helping you decide which pieces of equipment to buy. But when it comes to subwoofers, and especially to subwoofers this powerful, that thought goes out the window. You’re dealing with a very specific part of the frequency spectrum. Although human beings can only hear down to around 20Hz, we can actually feel frequencies lower than that. The Thor’s Hammer goes all the way down to 10Hz, which is nothing short of remarkable. Its party trick is that it reproduces the lowest note of a pipe organ with perfect fidelity and clarity at full volume. Since that note occurs at 16Hz, below the range of human hearing, that’s quite something.
See the Wilson Audio Thor’s Hammer
|Q Acoustics Q B12||$599||220||12"||Front-Firing||28-300Hz||17.5" x 15.7" x 15.7"|
|Monoprice 9723||$146||150||12"||Front-Firing||50-250Hz||17.5” x 17.3” x 17”|
|SVS SB-3000||$1,100||800||13"||Front-Firing||18-270Hz||15.7" x 15.6" x 15.2"|
|Sonos Sub||$699||Unknown||Unknown||N/A||Down to 25Hz||15.8” x 15.3” x 6.2”|
|BIC America F12||$210||150||12"||Front-Firing||25-200Hz||17.25” x 17” x 14.75”|
|Seaton Sound JS12||$1,395||700||12"||Front-Firing||20-200Hz||18” x 15” x 14”|
|Power Sound Audio S3612||$2,400||1,920||2 x 18"||Front-Firing||16-100Hz||28” x 24” x 20”|
|RSL Speedwoofer 10S||$399||350||10"||Front-Firing||24-200Hz||16.75" x 16" x 15"|
|ELAC Debut 2.0 SUB3030||$640||500||12"||Front-Firing||25-150Hz||18” x 17” x 17”|
|PSB Alpha S8||$449||150||8"||Front-Firing||35-150Hz||15.75" x 12.5" x 11.5"|
|Aperion Bravus II 12D||$999||500||12"||Down-Firing||19-350Hz||17" x 15.5" x 15.5"|
|Paradigm Defiance X10||$999||300||10"||Front-Firing||30-120Hz||16.5" × 15.75 × 15"|
|REL Acoustics HT/1003||$498||300||10"||Front-Firing||28-150Hz||13.8" x 13.7" x 12.5"|
|Monoprice Monolith M10-S||$523||500||10"||Front-Firing||28-200Hz||16.3" x 15.2" x 12.6"|
|Polk PSW505||$249||300||12"||Front-Firing||28-125Hz||17.5” x 16.5” x 15”|
|Wilson Audio TH||$25,000||N/A||2 x 15"||Front-Firing||10-150Hz||59" x 25.25" x 20"|
*RMS = RMS Wattage
**Freq. = Frequency Range
- Passive vs. Powered Subwoofers
- Front-Firing vs. Down-Firing Subwoofers
- Driver Size Explained
- Wattage Explained
- Ported vs. Sealed Subwoofers
- Wireless vs. Wired Subwoofers
- Subwoofer Placement Explained
- Setting Up Your Subwoofer
- Subwoofer Crossover Explained
- Using More Than One Subwoofer
- Subwoofer DIY Explained
There are two types of subwoofers: passive and powered. The difference between them is very simple. Passive subwoofers require an external amplifier to work, while powered subwoofers have an internal amplifier, and just need to be plugged into the mains. That’s it. We aren’t really going to talk about passive subwoofers here. Firstly, they are far less common than powered subwoofers, especially in the home theater space - although there are some still available, like this Bose PS 28 III. Secondly, going into the process of matching a passive subwoofer with an amplifier is an entire guide by itself.
Fortunately, we do have such a guide to matching speakers and amps, but in this buying advice, we’re going to be talking about powered subwoofers exclusively. The benefit of doing this is that it vastly simplifies the process of connecting your subwoofer to your system: all you have to do is run an RCA cable between them (most receivers have a dedicated subwoofer output), and a power cable from the subwoofer to the wall socket. Boom. Done. Trust us: it’s a good thing that the subwoofer is powered. You’re going to need a lot of power.
So: you’ve decided to buy a subwoofer. Congratulations. You’ve only got about 10,947,084 models to choose from, and that’s just on the first page. Subwoofers are further split into two categories: whether they are front-firing or down-firing. Figuring this out is easy. If the driver (the big, circular element, which is the same in terms of functionality as the ones found on floorstanding speakers) is on the front of the unit, then it’s front-firing. Bottom? Down-firing.
You might reasonably ask what the differences are between the two. There aren’t actually that many – not enough, given the variances between different rooms and different circumstances, to make a major difference. Bass frequencies are nondirectional, which means that it’s not going to matter that much which one you pick.
However: if you’re planning on placing your subwoofer close to your main speakers, or underneath your TV (and we go into placement in more detail below), then it may be worth investing in a front-firer. Away from your speakers? At the side or in the corner of the room? Go for down-firing. But again, this isn’t a decision which makes a major impact, and in this case, consider what we are saying as general guidelines rather than hard rules.
In the case of subwoofers, size really does matter. To produce bass sounds, you've got to be able to produce a lot of energy. The bigger your speaker driver, the more energy you'll be able to put out (although a lot of it has to do with the amplification powering the driver as well). In general, you should be looking to acquire a subwoofer with a driver above 12" in size - that's 12" across, from end to end. Anything smaller will deliver good sound, but don't expect huge low-end power. The PSB Alpha S8, which costs $449, has a driver of 8". We think it's good for small rooms, but you shouldn't expect it to put out huge energy.
That being said: you don't have to push the boat out if you don't want to. A 15" driver Will be perfectly suitable for most people, and only those who have very, very large rooms or need to produce seriously dramatic bass need to stray into the 18" and up range – For example, the Power Sound Audio S3612 which costs $2,400, and has twin 18" woofers. Always take into account the size of your room before you get busy with the one-click-buy!'
Spend any amount of time on this site, and you'll see this term a lot. We're sort of obsessed by it. Broadly speaking, the more watts there are, the louder the sub will go, although it’s a bit more complex than that—you can, after all, turn a sub down. Rather, think of wattage as a range in which you push the sub. The higher the range, the louder you can make it without distorting the sound. Watts can be low (60W) or exceedingly high (4,000W), and as you can imagine, you pay more for higher wattage. Note the difference between RMS (sometimes called continuous) and peak (sometimes called dynamic) wattage. Always, always, always look at RMS, and ignore peak. The former refers to the overall power at a set and usually reasonable volume. The latter refers to the absolute loudest the thing can go. You'll need the first. Don't believe the hype. Anything with up to around 1,000 watts of RMS power should be more than appropriate for most people, although you can go significantly higher if you wish to. For example, the Power Sound Audio S3612 puts out a staggering 1,920 watts, Which is overkill for just about everyone except those with underground bunkers.
Of course, you might reasonably ask: if you have two subwoofers, one with an RMS and peak of 500 and 1,500 watts, and another with an RMS and peak of 2,000 and 3,000 watts, then what’s the difference between them, given that they are both separated by 1,000 watts? The answer is in the nature of bass itself. Unlike higher frequencies, bass needs a lot of energy. The more wattage a subwoofer has, the more it will be able to provide that energy, at any volume. More wattage equals bass that is tighter, clearer, more well-rounded. It means that whether you’re rattling the windows or turning things down late at night, you’ll be able to get better sound. Once again: you control the volume. What you don’t control is the base-level clarity of the sound, and that’s where wattage can be a useful metric.
We agonized over this section. It is so, so easy to get lost in mathematical formulas and tables of figures when calculating exactly how wattage relates to decibel levels (read: volume). Ultimately, we decided that we’d keep things simple. If you have one takeaway here, it’s this: buy a subwoofer with a nice, wide gap between peak and RMS, and get one with as many watts as you can afford.
Sealed subwoofers have a cabinet that is entirely enclosed, with no openings into its interior. Ported subwoofers have one or more openings, to allow the free-flowing movement of air. Put very simply: sealed subwoofers sacrifice a little overall volume and presence for a tighter, more controlled sound, while ported ones can pump out huge volume at the expense of a little clarity. Generally speaking, larger and more expensive subs tend to be ported, while smaller, cheaper ones do not.
If you’ve got a smaller room, and don’t need to blow the windows off, then it may be worth looking at a sealed subwoofer. If you aren’t going to be pumping things to huge volumes anyway, then it makes sense to invest in a little bit more clarity and depth to the sound, rather than plumping for huge volume. But if you have a bigger space, consider ported models. You may also come across things known as passive radiators. Think of these as unpowered speaker drivers which are there to simply react to the air the main driver is moving. A subwoofer could have one or more of these in addition to the main driver, and they help with the articulation and expression of the sound. Passive radiators are almost always a good idea.
There’s an easy dichotomy here. Most home theater or hifi subwoofers have wired connections, while many that come with soundbars are entirely wireless. Wireless subwoofers have the advantage of needing absolutely no setup. They will already be slaved to the central unit, and all you need to do, in most cases, is plug them in. The crossover point (see below) is already set, so they take the difficulty out of initial setup, although you will of course need to work out where to put them, and they will need to be plugged into a mains socket.
The downside is that in almost all cases, they don’t sound quite as good as wired subwoofers. This isn’t a universal rule, and the private wireless network they run on is certainly capable of transmitting some good low end, but we almost always prefer wired models. This isn’t a decision we can make for you. The only thing we can say is that if you intend on having a 5.1 or 7.1 sound system, then we strongly recommend a fully-wired subwoofer - although there are always exceptions, like the excellent Sonos Sub.
There are some people who will tell you that it doesn't matter where you put a sub, as long as you're not using it as a table next to the couch. Don't believe these people. They're talking out their backsides. Placement is important, and you need to spend a little bit of time getting it right. This isn’t as easy as you might think. Oh sure, you could stick it in the corner of the room, or under your TV set, and you’ll get a reasonable amount of bass. What you won’t be getting is the timbre of the bass, its characteristics and color. It's like paying a lot for an expensive meal, and tasting nothing but salt.
Subwoofers are tricky in this respect. Bass waves move in all directions, and as soon as they hit a flat surface (like a wall) they reflect all over the place. Fortunately, there’s a neat trick you can use to simplify things. Put the unit in the place you would normally sit, then start playing some bass-heavy music through it–something like Skrillex or Diplo would be ideal. Now you need to crawl around on the floor (yes, we know) and find a spot where the bass sounds richest. You may have one or two spots to choose from at the end, but those are the spots where you should conceivably place your sub.
There are also plenty of outlets that offer dedicated online system builders, which will let you plug in the size of your room and help you fine tune placement. SVS has a very good one.
Usually subs are simple to set up. Plug an RCA cable (make sure you have one long enough) into the line-in port in the back of the sub, and to the subwoofer out on your receiver or amplifier. All that’s left to do then is connect the power cable. OK: sometimes it’s a little more complicated than that, a factor which largely depends on the rear panel of your subwoofer. The more expensive model is, the more likely it will come with a variety of switches and controls that let you adjust things at source.
Let’s tackle a few of these. If you see a volume knob on the back of your subwoofer – something that is rare but not unheard of – set it at about halfway. You can adjust it later, but you’ll be calibrating your sub to get the best sound, and the twelve o’clock position is where you want to keep it for now. You might also see a switch or setting labelled phase. The simplest explanation for this particular setting is that multiple speakers sound better together when their drivers are moving “in phase” – as in, in sync with one another. The kicker is that it’s often quite difficult to figure out if you’ve set the phase correctly (phase is almost always available in two settings, 0° or 180°). You need to spend some time sitting in your listening position, listening to something with a lot of bass content, then flipping settings and listening to the same thing. Without putting too fine a point on it, one should sound “right”. If you can’t hear a difference, or both sound okay, then our advice is: don’t stress. Pick one setting, and leave it there. You can always change it back later. You may also have various other ports on the back of your subwoofer, such as speaker outputs. For these, we are going to recommend that you consult your subwoofer’s manual. Every sub is different, and we don’t want to give specific guidelines here.
Welcome to the single most important thing you can do to make your subwoofer sound better. As you've probably figured out by now, a subwoofer is designed to handle the low frequencies. But as well-designed as your speaker system is, it’s not actually sentient. It doesn’t know where those low frequencies begin. There’s a huge range where they occur, and until you tell it differently, your speaker system may be diverting some of the low-frequency information in your sound to your surround or front speakers - information that would be far better handled by your sub. Adjusting that point - the frequency below which all sound is sent to your sub - is called adjusting the crossover point.
Usually, the crossover is set using the on-screen setup for your AV receiver. It should allow you to pick a particular frequency without too much trouble. To find the best frequency, what you need to do is go and look at the specs for the other speakers in your system. Every speaker has a frequency range it can comfortably reproduce. While they are completely useless when making a buying decision (something we’ve explained in detail here) they are very helpful for determining the crossover - which is why we've included them in our comparison table, above.
Let’s say you’ve got a set of speakers with a frequency range of 100Hz - 20kHz. That means your crossover point is 100Hz – that’s the point at which the speakers will stop being able to produce sound, which is where you need to bring your subwoofer thundering in the fill the gaps. Once you’ve set the crossover (and run your receiver’s room calibration software, if it has any), there’s one last thing you need to do. Start playing a song with a lot of bass content, at a reasonable volume, through your system. Lower the subwoofer volume until you can just barely hear the bass. Then, very slowly, start to turn it up until the bass is at a comfortable but not overpowering level. Congratulations, you’ve effectively matched your subwoofer with your speaker system, and no matter how loud you turn up the overall volume, the bass will not overpower the other speakers. Remember: wall-shaking bass is all well and good, but the key here is synergy. You want an overall sound that is rich, powerful, and deep, without being uncomfortable. Setting the crossover and the volume is the best way to achieve that.
If you think the bass is good with one unit, then wouldn't it be better with two? Or four? The answer is yes, of course it would, but you also run the risk of distortion, or simply overwhelming the other sounds in the mix. If you do want to try this, and have got the cash to throw around, then a unit in each corner of the room (although not up against the walls, please) will blow your mind.
But it certainly isn't essential, and if you make the right pick, you'll have something you'll love. Frankly, we'll take that over spending a huge amount of money on multiple variations of the same thing, just to produce endless bass. Unless you really, really want to annoy your neighbours. Or you live in the middle of nowhere.
One of the most common enquiries we get is whether we'll ever feature DIY subwoofers on The Master Switch. The builders of these subs contend – possibly with some merit – that their creations will easily outdo those made by some of the companies on our list. Our response is that it's very difficult for us to review a DIY sub – while it makes a fun read, and we love hearing them, it's not very useful for a reader who then decides to buy it!
However, we do recognize that DIY subwoofers are a huge market, and those who build their own spend a staggering amount of time getting it right. There are thousands of forums, subreddits, and other sites where builders post their work, and you'll often see DIY builders at audio shows. Hell, Dayton Audio even offer a basic starter cabinet, for those just getting into it.
Unlike many other speakers, subwoofer is comparatively easy, and it makes a great project if you're just getting started in the world of DIY audio. The components can be sourced from relatively little outlay, and you don't need a huge amount of electrical knowledge in order to build something you'll be proud of. While we will say that we aren't really the right site to find information on this, there's a wealth of information out there. If you get started, and you're not a giant ass-hat, you'll quickly find yourself making friends in the community.