I probably don’t need to convince you that HDTV is a spectacular viewing experience, with astonishingly lifelike images. But to enjoy all the benefits of HDTV and DVD, you need a multichannel surround sound system.
Let’s face it — TV speakers are better than they used to be, but most of them still aren’t great. Some video displays don’t even have speakers. To maximize the impact of home theater, you need an audio system that literally surrounds you with great sound — from the most explosive action-movie mayhem to the subtle ambience of a gentle rainfall or rustling leaves.
Equipment Essentials
Aside from source components like a DVD player or an HDTV tuner, you need two es sential things for home theater surround sound: an audio/video or “digital surround” receiver and a multichannel speaker system.
An A/V receiver is your home theater’s control center, providing amplification for the main speakers, volume control, source selection, decoding for Dolby Digital and DTS surround sound, and other features.
Most home theater speaker systems come in a 5.1-channel configuration, with speakers for the left and right front channels, two more for the left and right surround channels, a center-channel speaker, and a powered subwoofer. (The subwoofer channel contains bass frequencies only, hence its “.1” designation.) You’ll also find receivers and speaker packages for 6.1- and 7.1-channel systems, which have one or two back surround channels for speakers centered behind the listening position. But to keep things simple, we’ll stick with the popular 5.1-channel setup.
Hooking It All Up
You’ll be happy to know that — unlike so many other things in both life and home theater — connecting the source components and speakers to a receiver is easy. First we’ll make the basic connections, and then set up the speakers and receiver.
All recent A/V receivers let you connect sources using either digital or analog audio inputs. To get surround sound, you’ll want to use the digital connections. (The standard left and right analog audio connections are stereo only.) To accommodate high-def shows with Dolby Digital 5.1-channel surround sound, HDTV tuners, cable boxes, and satellite receivers, as well as integrated HDTV sets, all have digital audio outputs. Since most DVD movies have multichannel Dolby Digital or DTS soundtracks, you’ll find them on DVD players as well.
You can use either the coaxial (RCA) or optical digital audio jacks. Most recent receivers include multiple digital audio inputs so you can enjoy surround sound from several home-entertainment sources.
Note which components you’ve connected to which digital inputs on your receiver, because you’ll need to use the setup menu to tell the receiver that your program sources are sending it digital audio. DVD-Audio and Super Audio CD players, and “universal” players that play most surround sound formats, are the exceptions to the rule of “digital only” audio connections. These players have a set of six analog audio outputs that connect to corresponding input jacks on the receiver to deliver multichannel sound.
Use speaker cable to connect the left and right front, center, and surround speakers to their speaker terminals on the back of the receiver. Make sure the connections are in phase — that is, connect each speaker’s red (+) terminal to the corresponding red terminal on the receiver, and do the same for the black (–) connections. Otherwise the bass will sound thin and imaging will suffer.
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With a newer receiver, connect the subwoofer output directly to the subwoofer’s line-level (unamplified) Sub or LFE (low-frequency effects) input. (With older receivers, you might need to connect the sub between the receiver and the left and right front speakers using speaker cable.)
You’ve now made all the connections. Double-check them before moving on — you don’t want to find out you got your wires crossed after you’ve moved that heavy equipment cabinet back into place.
Speaker and Receiver Setup
Proper speaker setup makes the difference between a seamless 360° sound field that draws you into the onscreen action and an array of disconnected boxes blaring at you. Symmetry is critical. Speakers won’t “image” properly — that is, place the dialogue, music, and effects within the sound field at the correct distance and direction — unless they’re set up as symmetrically as possible.
The most common home theater setup has the left and right front speakers to the sides of the TV with the center speaker atop the set. The subwoofer is the front corner and the surround speakers are just behind and above the listening position on the side walls.
Almost all front speakers are direct-radiating (above left), while many surround speakers are bipoles or dipoles (above right), with sound radiating equally from the front and back of the cabinet.
Position the left and right front speakers like mirror images of each other, either facing straight out or “toed in” toward the listening position at the same angle. Often, the owner’s manual will recommend which orientation is best. Ideally (you might have to allow for your TV, room, and furniture), the speakers should be about the same distance from each other — far enough apart for a good stereo spread — as they are from the listening position. Divide the wall behind the speakers into thirds and place the left and right speakers at the one-third and two-thirds points, then move them an equal distance out into the room. Experiment with different speaker placements to achieve the smoothest blend between the three front speakers. If you mount the left and right front speakers on stands or on the wall, make sure their tweeters are at or close to ear level when you’re sitting down.
The most common place for the center speaker is atop the TV, slightly behind the left and right front speakers (if they’re not wall-mounted) and no more than 2 feet above or below their tweeters. Some companies recommend placing the three front speakers in an arc, with all three equidistant from the listening position. With a flat-panel TV, you can mount the center speaker above or below it, tilted up or down toward the listener to achieve the best blend with the left and right front speakers.
Just placing the center speaker atop most TVs would send the sound over your head. Almost all center speakers are designed to allow you to tilt them toward the listening position.
There are two kinds of surround speakers: front-firing, or direct-radiating — the type included with most satellite/subwoofer systems — and dipole or bipole, which radiate equally from the front and back to create a more diffuse sound. Mount direct-radiating surround speakers on the side walls, slightly behind the listening position and above ear level. Aim them into the room, unless the manufacturer recommends otherwise. If you can’t mount them on the side wall, place them along or on the rear wall, aimed toward the front of the room. Mount dipoles or bipoles on the side walls slightly behind the listening position and above ear level, with their driver sides facing forward and backward and the “null” (cabinet) side pointed toward the listener.
Subwoofer placement can be tricky, because all rooms have nodes — areas that weaken or strengthen bass. Place the sub in the front corner, and after working through your receiver’s setup menu (covered below), use the sub’s controls for level and — if it has them — crossover frequency, phase, and equalization to adjust it for a smooth bass-to-treble balance with the five main speakers. (See the owner’s manual for setup advice.) If you can’t get a seamless blend, place the sub on an angle in the corner (if the driver fires from the side of the cabinet) or move it to a back corner.
Setup Menu Selections
You’ll need to set the receiver, using its onscreen or front-panel setup menu, to match your program sources and speakers. As noted, the digital audio outputs from your program sources have to be assigned to the corresponding digital inputs on the receiver. Speaker configuration is done using the speaker-setup (or bass-management) menu.
The menu will ask you to select “large” or “small” for each of the five main speakers. If you have a subwoofer — the most common arrangement — select “small,” and select “on” for the sub. (“Small” and “large” refer to the speakers’ ability to handle bass, not their actual size.) Many receivers have more bass-management capabilities that allow for precise sound tailoring.
You’ll next need to compensate for the speakers’ varying distance from the listening position so that the sounds will arrive there at the same time. This helps to ensure that the sound field is as realistic as possible. Almost all receivers let you enter the distance of each speaker from the listening position and then set the correct time delay automatically.
Next, balance the speaker levels. While a few receivers (like the Yamaha RX-V750 reviewed in the September 2004 issue) fully automate this process, most simply send test tones to each speaker and the sub in turn so you can adjust their volume. If you have to set the levels manually, pick up an inexpensive sound-level meter at RadioShack (if the remote doesn’t have one built in). Stand behind the listening position and hold the meter where the listener’s head would be, with the microphone pointed toward the ceiling. Use the remote to adjust the level settings for each speaker until they’re all at the same volume.
Final Steps
Before you enjoy your system’s splendid surround sound, there are just a few more options to consider. Many DVDs have both Dolby Digital and DTS surround soundtracks, and all newer receivers let you pick which format you prefer. They also offer DSP (digital signal processing) modes that derive 5.1- to 7.1-channel surround sound from two-channel stereo sources and older, four-channel surround formats like Dolby Surround (used for many TV shows). And they have a selection of DSP ambience modes meant to create the illusion that you’re listening in, say, a jazz club or concert hall.
Also, consider your room acoustics. The room has a major effect on the sound of your system, so if it sounds too reverberant and “bright” (treble-heavy), add rugs, tapestries, or drapes to dampen things down. Removing the same items will help if the sound is too dull or “dead.”
With surround sound completing the picture, you’ll be transported down onto the field in a football game or into the battle for Middle-earth — right in your home. To paraphrase the words of Al Jolson: until you’ve heard surround sound at home, you ain’t heard nothing yet!