Typically a speaker system in a home theater will contain 1 subwoofer, as that’s what most systems come with. However, there can be some benefits to including 2 or more subwoofers in your home theater system. This is particularly true if you’re upgrading to a more advanced home theater system.
The most notable pros and cons to having 2 or more subwoofers in your home theater are:
- Better bass quality
- Widens listening area
- Greater flexibility in audio output
- More subwoofers means greater headroom
- Greater flexibility with placement
- Harder to find the sweet spot
- Your budget might not stretch
- Incorrect placement can have a big impact
I’ll discuss these in much more detail later in the article, but first it’s worth looking at why you might want 2 or more subwoofers in your home theater, along with how you’d go about fitting them in. Having this information will make the pros and cons easier to comprehend.
Why 2 subwoofers in a home theater
Generally speaking, the reasons why you’d want 2 subwoofers in your home theater are the same as why you’d want 2 of anything: more power and greater flexibility. While I’ll discuss these properly in terms of pros, it’s worth mentioning them briefly here.
2 smaller subwoofers will usually provide more power (and therefore higher decibel output) than a single large subwoofer. While this isn’t always the case, as some large subwoofers are capable of kicking out some serious bass, it holds true for most mid-range, commercially available subwoofers you’d find in a home theater.
The second reason you might want 2 or more subwoofers is that it gives you greater flexibility, particularly in large rooms. A single subwoofer will have a smaller listening area than 2 subwoofers, which will create a larger sound arc, therefore filling a larger room more easily.
The important thing to bear in mind is that adding an extra subwoofer isn’t necessarily about adding more bass to your home theater. An extra subwoofer allows you to manage the audio better, simply because you have more flexibility in volume, speaker placement, and so on.
Without covering too many of the pros in this section, this is basically why you’d want 2 or more subwoofers in your home theater. The number you include in your system will be dependent on many factors, but for most people, 2 subwoofers should be plenty.
How to install 2 subwoofers in your home theater
Before looking at how to install more than 1 subwoofer in your speaker system, it’s worth noting that ideally the subwoofers should be the same brand. This is simply so you can be more certain they’ll produce the same sound quality, and have the same low-frequency tones.
This doesn’t mean, however, that they need to be the same size. More advanced audiophiles might find some benefit in combining a 12-inch sub with an 8-inch sub, or mixing and matching different brands for their different sounds.
However, this is quite advanced sound engineering and should probably be saved for later. If this is something you’re interested in, this forum post is a good place to start.
As most AV receivers will only have 1 subwoofer port (if yours has 2, then skip ahead), you’ll need to buy something like an RCA splitter so you can connect the 2 subwoofers to the same input port.
There are other options available, such as turning your subwoofers into a wireless system, but by far the easiest option is to just buy a cable splitter. This YouTube video is a fairly comprehensive guide of the different installation options for 2 or more subwoofers.
The actual installation process is generally fairly easy, but the more advanced part is calibrating the speakers for best performance. However, we all have to start somewhere, so providing you have the time to do this, adding an additional subwoofer might be a good way to level up your audio tech skills.
Advantages of 2 or more subwoofers
While I’ve touched on some of the more obvious benefits to multiple subwoofers above, it’s worth considering these points in more detail.
Better bass quality
As I mentioned above, adding multiple subwoofers isn’t necessarily about more bass. The main benefit is that it actually improves the quality of the bass you’ll hear in your home theater.
This is because having several subwoofers should drastically reduce, if not completely remove, room resonance. Multiple subwoofers can be positioned properly to take advantage of a room’s acoustics, meaning less reverberation and better quality bass in your listening position.
Almost all rooms have spots that impact listening quality. The benefit of having multiple subwoofers is that you can position them more dynamically to remove these weak areas, simply by having the sound come from more locations.
Widens listening area
All speakers have an optimum listening area, which is why speaker placement is so important. Ideally all speakers should point to your seating area so that you get the best sound possible. However, this isn’t always doable, particularly if you’re limited by something like where you can actually place your subwoofer.
Adding multiple subwoofers to your speaker system means you can widen the listening area, giving you optimum bass in multiple locations. This is particularly useful for large home theater rooms, or even for normal rooms that might have several seating locations.
Sitting at the periphery of a subwoofer’s sound arc can result in poor bass quality. Conversely, sitting in the wrong place can also result in too much bass, which in turn drowns out the treble from your satellite speakers. Therefore you should do everything possible to optimize your home theater’s bass output.
A good analogy would be trying to cool a room with a single standing fan. Directly in front of the fan will be nice and cool, but the effects will barely be noticeable the further away you move.
However, by adding an additional fan you increase how much of the room is cooled. This is effectively the same logic behind having multiple subwoofers because you’re expanding the area of sound output.
Greater flexibility in audio output
As I mentioned earlier, having several subwoofers of different sizes is more advanced, but will give you much greater flexibility over the quality of sound in your system.
For example, if you have a main large subwoofer that produces most of the sound, adding a smaller one can help to cancel out some of the larger subwoofer’s resonances, while also increasing the overall volume and reducing distortion at high volumes.
The thing to remember here is that there isn’t a single setup that’ll be right for everyone. Home theaters are quite a personal thing, as they depend on your space and needs, so it’s definitely worth doing a bit of research and deciding what will work best in your home.
More subwoofers means greater headroom
Headroom is one of those audio terms that’s thrown around in the home theater world without too much meaning. Simply put, headroom is defined as the ratio between the maximum audio signal a system can handle compared to the standard level it was designed for before distortion happens.
But what does this mean? If your system is designed for a standard output of 10 decibels, but is capable of putting out 30 decibels before distortion, then it has a headroom rating of 20 decibels. This article explains it in much greater detail, including both analog and digital sound.
What this means for subwoofers in a home theater is that, by including several, you can work the speaker drives harder with less chance of distortion, which is exactly what you want for those hard-hitting action films with plenty of explosions.
Greater flexibility with placement
Aside from the flexibility 2 subwoofers affords in terms of listening area, having several also provides greater flexibility in their physical placement. Simply put, 2 small subwoofers can often fit where 1 big one can’t.
This is particularly useful in smaller home theaters that still want impressive bass output. While it’s not necessarily a functional benefit, having more options for placement is definitely an aesthetic one. GIK Acoustics has written a helpful article about the options for multiple subwoofer placement.
Disadvantages of 2 or more subwoofers
Harder to find the sweet spot
Finding the sweet spot for speakers in a room is a process of trial and error, and is something that many home theater fans loathe. Luckily, it doesn’t have to be done that often, as it can be a time-consuming process.
This is particularly true when you introduce multiple subwoofers, and is even harder if they happen to be different sizes. Correct subwoofer placement should result in bass that fills the room and sounds like it’s coming from the satellite speakers, as opposed to the subwoofer itself.
When you try to do this with multiple subwoofers then you might be in for an impossible task. Because most speaker systems are designed for one subwoofer (often the one they come with), adding another one can tip it off balance, resulting in overly heavy bass.
However, if you play around with your speaker settings, and have the patience to optimize your subwoofers, the results are pretty impressive. This point shouldn’t be enough to put you off, but is definitely worth considering before you start.
Your budget might not stretch
A good quality subwoofer can run into the thousands of dollars, although most people are content with one in the hundreds. It almost doesn’t need saying that the likelihood of 2 subwoofers being more expensive than one is quite high.
However, there are a couple of ways around this potential problem. The first is to go lower down the list in terms of quality and power output, although I wouldn’t recommend this. If you find this is the only option available to you then it might be sensible to stick with one higher quality subwoofer.
On that note, the second option is to buy one subwoofer now with the intention of adding a second when you can afford it. If you decide to do this, make sure you buy the same subwoofer at a later date to ensure the best audio quality for your system.
In most situations 2 subwoofers will be better than 1, but overall audio quality should be your top priority. If budget is your main constraint, then work with it and stick with a single subwoofer for now.
Incorrect placement can have a big impact
When using 2 or more subwoofers in your home theater it’s impossible to understate the importance of correct placement. You need to find the right balance between subwoofer placement and your listening area.
One effect of improper placement is for one subwoofer to suck out bass from the other. This isn’t a proper industry term, but simply refers to the way in which one subwoofer’s room resonance will override the other, resulting in holes or dropouts in the range of low frequencies.
As stated, this is much harder to manage properly with several subwoofers. Several badly placed subwoofers will have a much greater impact on overall sound quality than a single badly placed one.
In short, if you decide to install a second subwoofer, be sure to do plenty of research about placement options, and consider having a second person handy to be your listener.
Some final thoughts
Overall, adding a second subwoofer to your home theater is a good idea. It’ll make a noticeable improvement to the audio quality and will mean you can pump the bass much louder than before.
However, bear in mind that finding the sweet spot is harder, but is possible with enough trial and error. As always, make sure you research your options and decide on which will be the best subwoofers for your home theater. Just remember, they don’t have to match, but this will likely provide the best audio.
Thanks for reading! Check out my top picks for subwoofers
Jason is a home theater expert with over 10 years of experience in setting up home cinema rooms and systems. What started out as a hobby soon transformed him into an authority in the audio-visual field. He is passionate about providing readers with accurate and up-to-date information on the latest audiovisual technologies and their applications for home theaters. Read more about Jason.