What Size Speakers Do I Need for My Room?
I know that it’s fun to have gigantic speakers in your home theater when you want to impress your friends, but what size speakers are really necessary? Do you need really huge speakers, and are they worth it? Yes. Yes they are…at all costs. The bigger the better! Monstrous, gigantic speakers sitting three feet away from your face and pumping out 105dB of ear-bleeding sound is exactly what you need! Just ask your spouse or the person sitting next to you. What? They ran out of the room screaming?
Actually, no, you don’t need Godzilla-sized speakers in every listening room. You also don’t want to be sitting around listening to sound from a small jobsite radio either. There’s a balance to be found. The truth is, I once downsized my speakers when I went from a larger room to a new home where my theater needed to shrink. I know, I know—that’s sacrilege…but, really, it makes a lot of sense. If you want to understand anything about room acoustics, remember this: Loudspeakers always interact with the room in which they are placed. That means that if you place really large speakers in a small room, the room is going to have an effect on the sound produced. Conversely, if your speakers are too small, you’ll end up with a situation where you have to drive them way too hard to fill the space—and you’ll risk distortion as a result.
So how do you size up the speakers to the room? Well, you start with the room.
What Size Room are You Trying to Fill?
Understanding your room is a big deal. While THX acts like its definition of a small, medium and large room is proprietary knowledge that they’d rather drag to the grave rather than divulge, the following definitions are going to get you in the ballpark:
- Small room: Anything under 1,500 ft^3
- Medium room: Anything from 1,500 ft^3 to 3,000 ft^3
- Large room: Anything over 3,000 ft^3
Another way to think of it is that a bedroom-sized listening room is going to be considered “Small”, a larger living space will be considered “Medium” and a room the size of a small banquet room (presumably with tall ceilings) will be in the “Large” category. We’re almost never dealing in Large rooms in the DIY (do-it-yourself) home theater realm. That’s good news because larger tower speakers can do just fine in medium rooms. The next things to look at are the dimensions and the listening position. Both play a part in determining what size speakers you may want to use.
Room Dimensions and the Listening Position
When I downsized my speakers, I did it because the speakers I had required a certain distance to the listening position before they would converge together and form a cohesive image. In essence, what I had was a pair of speakers that were trying to play well for a person sitting behind me, instead of where I was sitting. Since I was unable to move my sitting position, I decided to go for the next size speakers down that were made to work in a shorter room (in this case, one that was 13 feet long).
But that didn’t mean that I had to compromise on sound quality. I’m going to say this once, so pay attention, because it will change the way you think about speakers: Speaker size has little to do with the quality of sound you can expect to get. In Star Wars: Return of the Jedi, Yoda says, “Size matters not.” This principle holds true for speakers as well (with the hopefully-obvious exception of tiny cube speakers, that is!)
I know that likely goes against everything in you. It defies the logic of why larger tower speakers cost more and why they play lower and provide more output than smaller speakers. But consider this: a full spectrum of audio can be achieved through the use of a well-placed and well-calibrated subwoofer. So whether your main speakers can play down to 50Hz or 20Hz shouldn’t really matter. And there are very few tower speakers (though some exist) which can beat a traditional subwoofer at 20-30Hz in terms of tactile bass response that you can really feel.
But what about output? Larger speakers tend to have more output due to more drivers and additional power handling. While true, that’s of little importance if you have a smaller room and the room itself, through the acoustic principles of boundary gain and reflection, gives you enough output to hit the levels you want to listen at. It doesn’t do much good to buy a speaker with greater output and power handling if you are never likely to need or use it.
Quality Over Quantity
When you pick out speakers, check out the specification that gives you the Sensitivity rating of the speaker. This will be a number that indicates how much output it delivers when fed 1 watt of power and measured from 1 meter away. The more sensitivity a speaker has, the less amplifier power it needs to produce volume. That means you will be able to play that speaker louder than a comparable speaker with a lower sensitivity, assuming the amplifier is identical. A loudspeaker with a sensitivity rating of 85dB SPL is going to need a lot more amplifier power than one with a rating of 94 dB SPL. The bottom line is that you will want to take this into account when you pair speakers with your existing gear, or when you are shopping for a new AV receiver as well.
Some tower speakers also try to do too much. In attempting to play low enough to qualify as a “full-range” speaker, some models skimp on the important midrange, allowing those frequencies to get muddied a bit as the speaker dips down low to pick up the bottom end. A nicer pair of bookshelf speakers coupled with a subwoofer avoids this and lets the speaker handle high frequencies through the mid-bass range, which it can do without too much distortion or difficulty. How do you tell which towers are skimping? In general, they look like they’re trying too hard. A tower speaker that makes sweeping claims about how low it plays, while being really inexpensive, might be a good giveaway. You can’t have it all—at least not for a bargain price. I much prefer putting my money into a well-tuned bookshelf speaker that can give me good mids and highs. I’ll add a sub to pick up everything else.
What Size Speakers You Need Involves Lots of Factors
Adding to the above items, there are a few other things we might add to the list when considering speaker size and form factor. Here is a brief list of things you may want to keep in mind when determining what size speakers you need for your room:
- Small children fare better around tower speakers
If you have small toddlers in the home, or even active youngsters in general, keep in mind that a pair of bookshelf speakers on stands may not be the safest thing you can have in the home. I’ve seen a speaker or two fall in my day, and the floor isn’t the only thing that can get damaged. Keep this in mind as you shop.
- Are you primarily into movies or music?
If you’re a movie-buff you almost undoubtedly want to make sure you invest in a great subwoofer. That means it’s even more acceptable to go with a higher quality bookshelf speaker over a tower. If music is your thing, you may want to see if matching 4 speakers all around is something you can pull off. Whether towers or bookshelf speakers, matching 4-5 speakers all-around is definitely the way to go if you’re a die-hard music aficionado. What size speakers you get isn’t as important as making sure you match them where needed.
- What’s your upgrade path?
If you can think far enough into the future, you may want to invest in a pair of bookshelf speakers up front, along with a subwoofer. Then, when you’re ready, you can move those bookshelf speakers to the back and invest in a pair of good-quality tower speakers. The advantage here, of course, is that you may not be able to afford both towers and a subwoofer initially, so this is a way to step into a nicer surround system gradually. Planning your upgrade path is a skill we highly recommend you put some time and energy into—it can save you lots of money in the long-run and net you a much better-sounding system sooner than later. Check out our Upgrading Your Speakers Hassle-free article for even more advice on this topic.
- Cube speakers, contrary to marketing and infomercials, can’t defy the laws of physics
Despite what you may hear on TV or read in a magazine ad, tiny cube speakers cannot produce accurate sound. Here’s why: Cube speakers can’t play much below 150Hz, and the accompanying “bass module” can’t quite reach up high enough to fill in the gap. As a result, you get big frequency response holes that aren’t a problem with a real bookshelf speaker-subwoofer combination. That bass module also can’t deliver serious output below 40Hz, so you get a lot of boomy bass, but very little real tactile response. In summary, if cube speakers impress you in the store demo, its likely because you can’t compare them to a true surround system.
Remember what I said earlier: What size speakers you have does not determine, necessarily, the quality of sound you will get. There are tons of examples of bookshelf speakers sounding better than their tower-sized counterparts. Remember that a subwoofer is your friend—even for music-listening. Pair the speakers for the room and the listening position and don’t overdo it. If you are sitting less than 10 feet away from your speakers, a pair of towers may simply be too large to properly image well. Don’t be worried if your speakers don’t “look” big…you want them to sound big.