Better in Theory than Reality? Three Home Theater Ideas to Avoid
As the saying goes in life, so it goes in the wondrous worlds of Quality Home Theater and Hi-Fi: “Hindsight is 20/20.” I can’t even begin to list all of the hare-brained things I’ve tried in my quest for better sound and picture quality, only to end up making my system perform worse.
Most of my ideas were driven more by curiosity than anything else. But over the years, I’ve learned there exists a common set of ideas–nay, a universal wellspring full of theoretically genius yet ultimately fruitless “experiments”–that seemingly every home audio tinkerer draws from while attempting to tweak his system beyond all sensible limits. And while some home theater experiments might be a lot of fun, others just don’t cut the mustard in the real world. Here are Three Home Theater Ideas That Are Better in Theory Than Reality.
Building an Army of Front Speakers
This is the single-most common idea people mention when first exploring how to improve their sound: “Well, if having two speakers up front sounds good, I bet having four (or eight, or 12)of ‘em will sound even better!” Unfortunately, reality doesn’t support this theoretically excellent idea: More main channel speakers never equals better sound, only confused sound.
Reason being: High quality speakers feature carefully-designed dispersion patterns that, in large part, determine the sound we hear from them; adding more than one pair of main speakers results in a type of destructive interference that can wreak havoc on this dispersion.
In simplified terms, destructive interference causes the speakers’ multiple waveforms to interfere with each other in unintended ways. One of these ways is to literally cancel out certain ranges of sounds while doubling up on others. This leads to all kinds of bad sonic juju, including making instruments and voices sound unnaturally emphasized or suppressed in certain areas, destroying imaging quality, blurring sonic details, and diminishing overall clarity.
The best way to boost the front channels is to upgrade them to a larger, higher quality pair. With the right upgrade, you’ll experience increased dynamics, broader, more immersive coverage, and fuller, richer sound.
Note however that we’re talking about front main channel speakers only, not height or width speakers. The latter two output distinct sonic information that can enhance the theater experience, especially if your system resides in a large and/or dedicated theater room. If that’s the case, you’d probably want to outfit it with a 7.2 or greater system anyway for more expansive coverage and greater surround dispersion. But whatever you do, avoid the temptation to build an army of main channel front speakers: Your ears with thank you.
Mounting Your TV Above the Fireplace
This is, by a good margin, the most popular placement idea when it comes to the video side of things. Unfortunately, placing your TV this way always puts it much too high for optimum viewing. As a rule, your eyes should be roughly on axis with the center line of the TV screen, plus or minus 15 degrees max, when seated in your favorite spot and looking straight ahead. Too high, and you’ll be craning and straining your neck from tilting it back and looking up the whole time.
What’s more, viewing your television directly on axis means you’ll experience the best picture quality your TV has to offer. All TVs lose at least some brightness, contrast and color accuracy when viewed off-angle, and this can be doubly destructive if your TV’s too high and you’re positioned off at an horizontal angle; best way to avoid this is to properly position your set as centered as possible from the get-go.
Hiding Your Subwoofer Inside a Cabinet
Ever wonder how car audio subwoofers can get so excessively boomy? The answer lies in the standing waves that develop inside the car’s cabin. In simplified terms, standing waves happen when two opposing sound waves interfere with each other; think of a forward launching wave from the sub and a previous, reflected sound wave coming back and you get the basic idea. This causes persistent resonances at some frequencies while cancelling others–pretty much a very specific form of destructive interference. The result is that droning, one-note, booming sound you hear from a bass-heavy car.
Unfortunately, the same rules apply when you place your home audio subwoofer inside a cabinet, closet, or other furniture item–which means you’ll get excessively boomy bass in your pad, too. While at first it may seem like you’re getting more output this way, that’s only true at a few specific frequencies and select spots in the room: It will sound fine in one or two spots, but it will be dreadful everywhere else. Even in the locations where you might get decent bass, much of the clarity, weight and impact will be missing .
If space affords, try optimizing your sub’s placement in the room instead. Use the crawl method and other techniques described here to get smooth, consistent bass. Place acoustic bass traps in strategic parts of the room, and you’ll get bass that goes lower, louder, and cleaner than you ever could by making your sub resonate a cabinet. And yeah, we realize that doing all of this means your sub won’t be stealthily hidden, but following these few simple steps will ensure you’ll experience all of the performance your subwoofer is capable of delivering.
Oliver Amnuayphol is a independent Writer-at-Large with nearly 20 years of audio and home theater industry experience. He currently works as a reviewer for several publications, including The Soundstage! Network and Digital Trends. Find him on Twitter at: (@valvesnvinyl).