Loudspeakers have the toughest job in the home entertainment system. While source, processing and amplifier components like players, receivers and amps simply have electrical signals with which to contend, speakers are transducers devices which convert electrical energy (the audio signal supplied by the amp) into mechanical energy (the music and sounds we hear). A good speaker will accurately do this job; reproducing sounds precisely as they were recorded, and efficiently; squeezing the most volume from the least power. What's more, there's no single way to build a fine loudspeaker. Unlike amps, pre-amps, and processors, which all employ the same basic circuits but differ in terms of features and construction quality, the diversity of speaker designs is nearly as limitless as the speaker designer's imagination.
All loudspeakers make sound by moving air. Your amplifier powers the speaker's drivers-woofers for bass, tweeters for treble, and midrange for everything in between-which vibrate at frequencies and volumes to match the original recording. Since they all work the same, why don't all speakers look the same? Because everyone's needs are different. Do you want to make your home theater the focal point of your living room, or do you believe that speakers should be heard and not seen? Are thunderous bass and lifelike volumes important, or is softer better? No matter: there's a perfect speaker for your room, budget and listening taste, once you know how to find it.
In addition to playing music, the left and right main channels of a soundtrack carry most of a motion picture's special effects and orchestral score. In order to excel at these tasks, the stereo pair must encompass wide frequency and broad volume swings (dynamic range), reproduce subtle recorded details, and be able to create a convincing soundstage (the impression of three dimensions). When choosing main channel loudspeakers, play a handful of music and movie selections you know well. Listen to a solo vocalist. Does the image of that performer seem to float at the center of the soundstage (good), or can you trace the singer to the speakers (bad)? Next, try an acoustic guitar, violin or cello. You should hear natural, detailed string tone, as well as the resonance of the instrument?s wooden body. Finish with an action flick. Are the effects-gunshots, explosions, etc-clearly reproduced, or do they become hard, flat and generally unpleasant as the volume increases? A good pair of loudspeakers should never sound fatiguing.
Although listening is the ultimate test of a loudspeaker, there are other clues to quality. Rap your knuckles on the sides of the cabinet: a hollow thud indicates a poorly made enclosure that will probably degrade the sound. The weight of a speaker will give you a clue as to the materials and construction quality. The best speakers offer 5-way binding posts that offer the best possible connection with any type of cable.
Floorstanding or tower loudspeakers are audio's equivalent of a big-block V-8 engine. Thanks to their large enclosures and increased size or number of drivers, floorstanders move enormous quantities of air, enabling them to have greater dynamic range (to play louder and cleaner) and produce deeper bass than other designs.
- Extremely wide frequency response and dynamic range make floorstanders the choice where performance is the primary purchasing criteria. And while they tend to be large, many current models feature slender cabinets with small footprints, minimizing placement difficulties and visual impact. Also, since most of the world's best loudspeakers are towers, their manufacturers often lavish better parts or build quality on these flagship products.
When space is at a premium, such as in a small apartment or smartly decorated room, towers simply might not fit. What's more, the prodigious output capabilities of such speakers means that placement can be more critical floorstanders should be located 2-3 feet from nearby walls for best performance. Finally, beware of bargains: large cabinets are expensive to build. Unusually low pricing is often the result of construction shortcuts.
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With their compact cabinets, bookshelf speakers work where towers won't. Actually, the name bookshell is unfortunate, since most such designs perform best when placed upon rigid stands, rather than tucked inside pieces of furniture. These speakers are not only more placement friendly but, since small enclosures are more rigid, they produce less sonically degrading box resonance than all but the best towers.
- Usually modest in price as well as size, bookshelf speakers fit rooms and budgets that cannot accommodate a pair of towers. The small, solid cabinets are both versatile-able to excel in bookcases, atop shelves or hung on walls-and feature excellent midrange clarity. Caution: Many speakers use air tunnels or ports to improve efficiency and bass output. If you plan to place your speakers against a wall or inside a cabinet, choose a model whose port is located on the front panel, with the drivers. The exceptions to this caution are the Polk RT Series bookshelf models that feature a rear mounted PowerPort. The PowerPort's unique design permits proper operation under these conditions. (Couldn't resist the plug here!)
Reduced cabinet volume and driver surface area limit the dynamic and bass frequency range of bookshelf speakers, and can also compromise power handling and efficiency. Fortunately, the addition of a subwoofer can overcome these problems.
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When even the smallest bookshelf speakers are too visible to fit your lifestyle, a subwoofer/satellite (sub/sat) system is the answer. By combining palm sized satellites with a subwoofer designed specifically to work with them, sub/sat systems have become one of the most popular categories in home audio.
- The big advantages here are size, placement flexibility and cosmetics. The satellites can be placed just about anywhere, on a shelf, on the wall, in a cabinet or on a table. Most are small enough to fit in the palm of your hand and are hard to spot when placed alongside books and bric-a-brac. Some of this genre are very handsomely styled so that even when they are seen, they complement rather than detract from the look of the room. The subwoofer section can be placed out of sight - in a corner, behind furniture, or under a table. Sub/sats also have certain performance advantages over more traditional designs. The slender front baffles cannot interfere with the drivers' dispersion, so imaging is absolutely first rate. The best of the genre produce a wide, deep soundstage that is in some ways superior to larger speakers. The subwoofer cabinet can be placed where bass performance is best (near wall or corner), so bass response is often awe some. Most folks are agog when they hear such loud bass apparently coming from two tiny speakers.
Those little satellites cannot reproduce bass of their own, making it tough to achieve a seamless blend between satellite and sub. There is often a hole or weak response in the lower midrange area (bottom range of a male voice) where the satellite's response leaves off and the subwoofer takes over. When evaluating sub/sat systems listen closely to male voices, if they sound thin the system suffers from this midrange suck-out problem. These systems' small drivers and enclosures compromise dynamic range and power handling. If you have a very large room to fill with sound, a sub/sat system may not be right for you. The other issue is bass response. Some of the so-called subwoofers in these systems are passive (not amplified) and should really be called "woofers" because they don't reproduce the truly deep bass with authority. If the system is to be used for only music, that may not be a problem. But if the primary use is home theater, you may later find the need for an additional powered subwoofer. Many sub/sat systems now come with powered woofers that are worthy of the name subwoofer. As always, listen before you buy and trust your ears.
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For environments where box-type (tower or bookshelf) loudspeakers are unacceptable, in-wall speakers flush-mount in holes cut into the sheetrock of your walls. Most models feature paintable grilles so you can disguise them, enabling them to virtually disappear. Even the area of bass reproduction can be addressed with in-wall, in-floor and in-ceiling subwoofers. A completely invisible, no compromise sound system can be fairly easily obtained with this type of speaker.
- Since they consume no floor or bookshelf space and can be easily concealed, in-walls work when and where other speakers will not. If you plan to expand your system throughout your home, in-walls are a wonderful way to bring sound to additional rooms. They are also useful as rear surround speakers when the room configuration makes it impossible to properly place box speakers.
These days there aren't very many since this speaker catagory has made significant strides in the past few years. They can produce the same level of high performance sound quality as any other type of speaker.
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This article was last modified May 19, 2013