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Speakers: Where Do I Put Them? By Darryl Wilkinson September, 2007
Several years ago I was just setting up my current home theater room. While it was not scheduled to be equipped with multi-tiered stadium seating, faux art deco design, and a popcorn machine, I did have the luxury of setting it up strictly for movie and music listening. It didn't need to be compromised to serve any other purpose.
Even before started to set up a projector, I began by finding the best place for the speakers. But there was one important limitation: they had to be far enough apart to allow for placement of my 78" wide projection screen. Not at all incidentally, the choice of screen size was at least partially influenced by the spacing required for good two-channel music listening.
Only after the speakers were set up was the projector brought in.
Not all of you will have this luxury, of course. But both the placement of the speakers and the placement of the listener(s) affect the sound you'll hear. While necessity may require that speakers be set up close to walls, they will nearly always sound better if positioned at least a couple of feet away from the wall behind and a similar (but not identical) distance from the side walls (this does not apply to in-wall and on-wall speakers, which we are not addressing here).
A few years back, home theater designer Russ Herschelmann wrote several columns on this subject for the pages of the Stereophile Guide to Home Theater. Without going into the depth of detail that Russ presented there, here are a few suggestions inspired by those articles:
General Placement Tips
The rules of thirds and fifths are often good starting places for determining speaker and listener placement. Locate the speakers away from walls at a distance that's a multiple of thirds or fifths of the room's dimension in that direction. For example, if a room is 20 feet long and 15 feet wide, locate the left and right front speakers 4 feet from the wall behind them and 3 feet out from the left and right side walls. Locate the main listening chair 4 feet from the wall behind the listener (12 feet from the plane of the front speakers) or 8 feet from the wall (8 feet from the front speakers).
Try displacing the center speaker just a bit from the center of the room dimension at its sides. That is, instead of locating it 7.5 feet from each sidewall in the 15-foot wide room above, locate it 7 feet from one wall and 8 feet from the other. Yes, this will slightly disturb the symmetry of the setup, but could result in smoother response from the center speaker.
Avoid, if at all possible, locating the main listening seats hard up against a wall. Due to a well-known room effect (standing waves) low frequencies are emphasized near a wall and this listening position will seriously compromise any attempt at smooth, well-balanced bass.
Front Speakers
Sure, you will have a center channel speaker, but don't use this as an excuse to put the left and right speakers 15 feet apart. To provide the best combination of stereo spread, imaging precision, and coherence with the picture, a good rule of thumb is to position the left and right front speakers so that the distance between the two speakers is equal to or preferably even a little less than the distance from each speaker to the listener. For instance, having the speakers 7 feet apart, and 8-9 feet from each speaker to the listener is excellent. Avoid setting the speakers farther apart than the distance from each speaker to listening position if at all possible.
I also recommend placing the speakers a minimum of 7 feet apart for any listening position that will be 10-12 feet from the screen of a one-piece television, and no more than 10 feet apart if you can help it. For a front projection setup, position them no more than a foot or so to the left and right sides of the screen.
Many people sit too far from their TVs and/or their speakers. For a 7-9 foot speaker spacing, I recommend sitting no more than 8-12 feet from the speakers. Sit too close and the sound from each of the speaker's drivers may not "gel" properly into a coherent whole. Sit too far away and you'll hear too much of the room and, if you're really unlucky, an amorphous blob of sound instead of a well-defined soundstage.
Compact speakers are often referred to as "bookshelf" models. But that designation is misleading, as most serious "bookshelf" speakers are not designed to be used in a bookshelf at all. Instead, they work best when placed upright on good (extra cost) stands and located as described above--a couple of feet or more away from any nearby walls, including the wall behind them.
When possible, set up the speakers so that their drivers are aligned vertically. This will provide the smoothest off-axis response. Horizontal center speakers are an exception to this, but they can involve performance compromises. The horizontal configuration of the drivers in most center speakers is driven by aesthetic and marketing considerations, not the best sonic performance.
Many audiophiles
to set up their two-channel stereo systems with the left and right speakers aimed straight ahead, and some (but not all) two-channel setups sound better this way. That's fine for a single listener, but a disaster for several listeners watching a movie. If you're seated in front of the left speaker, it's firing right at you while you'll be so far off axis of the right speaker that you'll rarely be aware of it. Instead, for a more uniformly distributed soundstage try aiming the left and right speakers directly at a centrally located listening seat, or even at a point in space a couple of feet in front of it. You won't achieve perfect performance everywhere, but family and friends will thank you anyway.
If there's deep, big screen TV between the left and right front speakers, try to move the speakers out far enough that their front baffles are further forward than the plane of the TV screen. This shouldn't be difficult if you follow the recommendations above about keeping the speakers away from the walls. Keeping the speakers as far as possible from a TV will minimize acoustic reflections from the screen.
If you are still using a CRT TV, make sure your front speakers are magnetically shielded. For a modern digital television, such shielding is irrelevant.
Surrounds
Do put your surrounds along the side or rear, where they belong. In particular, if you have a small HTiB (home theater in a box) system, don't be tempted to forget the surrounds. The ambience and sense of space that properly positioned surrounds add can be even more impressive in an otherwise modest speaker setup than in a state-of-the-art system.
Dipole surrounds must be placed directly to the sides of the main listening seats for best results. For other types of surrounds, 110-120-degrees back from the front is often recommended as the best location for a 5.1-channel system, but don't be bound by convention here. If your room is fairly narrow, you may find that side or near-side mounting makes the surrounds too prominent. Try moving them further back, or even in the back of the room.
Subwoofers
We could fill an entire book on subwoofer placement and not say everything that can be said. Suffice it to say here that you just can't plunk the subwoofer down anywhere and expect to get the best from it. Experiment. Try different locations, and live with each of them for a while, listening for smooth, uniform response and good low frequency extension without boom or one-note bass. Some rooms will resist a good result more than others, but after a time you should be able to arrive at a satisfactory setup in nearly any room.
Configuring Speakers By Thomas J. Norton
August, 2007
When you get that new speaker set you're going to need to configure and balance your system. The process described below describes AVRs, but both the features and steps you'll take are identical if you're using a "separates" system with a pre-amp/processor and power amp.
Setup really isn't as complicated as many owners' manuals make it seem. All receivers guide you through the operation in their on-screen setup menus (some more successfully than others) by breaking it down into manageable chunks. The process is basically the same from receiver to receiver: source setup and identification, speaker configuration, delays, and speaker levels. And, in a growing number of AVRs, you can add automated setup and room equalization to this list.
Source Setup and Identification
In some receivers, this is a simple operation. You connect your DVD player to the DVD input, your TV audio to the TV input, your satellite input to the SAT input, and so on. There are separate inputs for analog and digital sources and, in most receivers, a way to switch between these analog and digital inputs. If you switch between active inputs and get no sound, the first thing to check is if you are trying to listen to a digital input with an analog input selected, or vice versa!
Some receivers may not label their inputs as DVD, SAT, TV, AUX, etc, but rather Analog 1, Analog 2, . . .Digital 1, Digital 2,. . .Component Video 1, Component Video 2,. . .HDMI. . .etc. These receivers let you assign each of these inputs to a specific setting on the input control and, often, then name the input in a way that makes it more intuitive to use.
Suppose, for example, you have two disc players: an HD DVD player and a Blu-ray player. Connect the HD DVD player to the DVD input and the Blu-ray player to the AUX input. Then as long as you remember what is connected where, you're good to go. But with other receivers, you can connect the HD DVD player to Digital 1 and the Blu-ray player to Digital 2, and then rename those inputs HD DVD and Blu-ray. In the latter situation everyone in the house knows exactly what's connected to each input.
There are also video inputs, of course. Generally, in a receiver that allows the more flexible input setup described above, you'll want to assign the audio and video connections of a given source to the same position on input selection control.
Speaker Configuration
The first thing you'll need to tell the receiver is what your speaker setup is and how you want it to handle the bass for each speaker in the system. In most cases, the options will be Large, Small or None. Often, these choices are limited in some way. For example, you can't select Small for the left front speaker and Large for the right front. You'll also be asked to specify if you have a subwoofer, and if so, the frequency below which you want the subwoofer to operate. Most (though not all) receivers offer a range of such frequencies; when in doubt, 80Hzthe frequency recommended by THXis always a good place to start. It works well with most speakers.
Selecting Large for a speaker allows them to operate full range. Small re-directs that speaker's bass below the specified crossover. If you have a subwoofer, the bass for the speakers designated as Small is redirected to the subwoofer; if not, it's redirected to the speakers that you've designated as Large. Some receivers complicate this by offering the option to redirect bass to both the subwoofer and the Large speakersan option we do not recommend as it leads to overblown bass.
In fact, just because some of your speakers are full range, with very good bass response, doesn't necessarily mean that you must designate them as Large, or even that this will be the best choice, if you have a subwoofer. You can select Small for them also, and let the subwoofer handle all the deep bassa setup I generally prefer. Even speakers offering more than sufficient bass for music can be overloaded with the bass from action soundtracks played back at high levels.
Speaker Delays
This part of the setup operation simply tells the receiver how far away from each speaker the main seating position is. Measure the distance from your favorite seat to each speaker and enter this value into the menu. Generally you will be offered the option to use meters or feet. Some early receivers specified the delay in milliseconds, but this is now rare. You might also find receivers that ask you to input the difference in distance between the main L/R speakers and each of the others. Thankfully, these are also uncommon.
Speaker Levels
All receivers provide a manual test signal that moves from channel to channel, along with the means to match the levels of each channel. Automatic level operation moves the calibration signal from one channel to the next in sequence, pausing at each step for a few seconds. With Manual operation you choose when to move on to the next channel. Manual is far easier to work with.
You can either level match by ear or by means of a sound pressure level (SPL) meter. Setup by ear is a quick and dirty alternative that can work satisfactorily, but an SPL meter is far more accurate. Radio Shack's analog SPL meter ($45) is a fixture in most home theater enthusiasts' tool kits. There's also a more expensive digital version; it offers more features, but the analog version is easier to use and is all you really need.
Equalization
A surprising number of receivers now offer some form of automated, onboard equalization performed using a microphone that's included with the receiver. The effectiveness of this feature will vary from receiver to receiver, particularly in the low frequencies where room compensation is most needed. While manual settings are often provided too, the automatic setup is far more preferable.
Unless you know what you are doing and have the right test tools, setting equalization by ear is a recipe for failure. These auto systems are a step in the right direction. There's no guarantee that you'll
the results, but if the receiver you buy has this feature, you'll want to at least try it out. The actual setup will vary from receiver to receiver, but the procedure is (usually) clearly described in the owner's manual and easily defeatable if you don't
the result.
Automatic Setup
The discussion of auto-equalization brings us directly to a feature that is now almost universal in receivers with any pretensions to high-end performance: auto setup. Using a microphone (included) positioned at the main listening seat, you merely engage the auto setup feature and go make yourself a sandwich while the receiver generates a set of test tones that determine all of the important speaker calibration settings: configuration, delays, levels, and equalization (when included). When you're done, you're ready to fire up the system.
Well, nearly. Often these automatic systems will make odd choices for the size of the individual speakers in the system. It might classify a L/R speaker pair capable of response down to 40Hz as Large, but has no way of knowing that these speakers overload easily with a high level, 30Hz signal. It might do the same with the center channel, or the surrounds. While that auto setup function can be a blessing, it's no miracle. A little intelligent oversight is your best bet. If you want to drive all of your main speakers as Small, just go into the menus after the auto calibration is finished and change the settings you see fit. The same applies if, for example, you want the surrounds levels a little higher, or the subwoofer level a little lower.
There's More?
There are a wide variety of additional features available on some receivers. Just a few of the features becoming common on AVRs are the ability to choose different crossovers for each channel, cross-converting all video sources to a single HDMI or component output, built-in video scaling, different setups for multichannel and two-channel operation, different ways of treating the LFE channel (the ".1" channel in a 5.1- or 7.1-channel system), and multiple zones of operation.
These features vary significantly from one design to another, but are rarely crucial to the basic setup described above. They sometimes clutter up the setup menus, but you can usually ignore them until you become familiar with you're receiver's basic operation. When you're ready, feel free to experiment with one or more of these advanced features, knowing that you can always go back to your simpler, trusty first setup at any time.
