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No part of assembling a high-fidelity music system is as important as choosing the loudspeakers. Everything you hear from an audio system comes from the speakers, and normally they are the only components in a system that directly affect the way it sounds (assuming that all the equipment is functioning properly).
Does that mean that everything else in the system is unimportant? Absolutely not all of it is needed to produce sound, and if any component does not perform adequately there will be some degree of audible degradation. But practically speaking, the quality of the sound you hear in a good modem hi-fi system is determined by the program source (nowadays typically a CD) and the combination of loudspeaker and room characteristics, which - interact very strongly. The acoustic treatment of the listening room and the placement in the room of the furnishings and speakers, as well as the listeners, can (and usually do) have a major effect on what you hear.
What we’re concerned with here, however, are the loudspeakers themselves. I wish I could tell each of you which loudspeaker to buy (or not buy). Unfortunately, that is not possible. For one thing, there are hundreds of speaker manufacturers and literally thousands of models to choose from, and the cast of players changes daily. I probably have tested as many speakers as anyone (well over 600), and it is a fact that most of them, while acquitting themselves well, have failed to achieve any sort of universally accepted classic status. Only a handful of exceptions come to mind, such as the Klipschorn, AR-1, and Quad Electrostatic, each of which represented a milestone in the speaker art. But you are facing the problem of choosing from among today’s speakers, not the classics of the past. Where do you start? This is a good time to point out the often over looked fact that loudspeaker selection is as personal and subjective a process as choosing a car, clothing, or the food you eat. Although there certainly are objective criteria for the performance of speakers intended for reproducing music in the home, personal preference plays an enormous role in making the final purchase decision.
As a rule of thumb, I suggest that your investment in speakers should be at least 40 or 50 percent of the total cost of your system. That is a flexible figure, subject to considerable variation according to the complexity of the system and its total cost, but it is a pretty good estimate for a moderately priced basic stereo setup. Just remember that no matter how fine the rest of the components in your system, playing them through $100-a-pair speakers will probably make the whole thing sound like something you picked up at a bargain sale. On the other hand, a good $3,000 speaker will usually sound first-rate even when driven by a receiver selling for a small fraction of that price. Those are extreme examples, of course, but they nonetheless illustrate an almost universal verity.
Disregarding price for the moment, let’s look at your options. The end use is an important factor. A system for a bedroom or another secondary system will probably be perfectly satisfactory with a pair of inexpensive bookshelf speakers. Almost any reputable recognized brand will do the job.
But for a system intended for serious listening, your standards are likely to be more rigorous in almost every respect. Often such a system is in stalled in a family living room, where it may be highly visible (as well as audible). Speakers differ greatly in size, I weight, appearance, and placement requirements, all of which should be evaluated in making a choice.
One of the most common speaker configurations is a simple rectangular box, sometimes small enough and light enough to be placed on a sturdy shelf, but often best suited to floor or stand placement. Especially in the low price range (but by no means limited to that), such speakers are usually two- way systems (woofer and tweeter) in a closed or vented box.
Despite their “bookshelf” format, these speakers often sound their best when placed on a stand a few feet from a wall. That may be inconvenient in small rooms, so take it into consideration when shopping. Try to listen to the speakers placed more or less the way they will be in your home.
An increasingly popular speaker configuration is the “three-piece” sys tem. As the name suggests, it consists of two small “satellite” speakers and a separate bass module (often optimistically referred to as a “subwoofer,” though in fact it is serving the function of the woofers in conventional speakers and rarely delivers deeper bass). A good three-piece system, though not necessarily inexpensive, meets a genuine need in many cases. The format lends itself to inconspicuous installation and can be almost invisible (I use such a system in our TV room, where it does an excellent job). The sound quality of a three-piece speaker sys tem can be surprisingly good, though not always the equal of some comparably priced conventional systems.
Large floor-standing speakers, although often of two-way design, are more likely to be three-way systems, with separate bass, midrange, and treble drivers. That does not, in itself, make a speaker better than a two-way design. In fact, some very expensive (and high-quality) speakers are two- way systems. But it may enable the system to use a larger woofer than would otherwise be practical, increasing the total amount of acoustical energy the speaker can produce.
The most fundamental advantage of a large speaker enclosure is its potential for an extended bass response. If efficiency and woofer size are held constant, increasing the enclosure volume will lower the frequency at which the bass response begins to fall off. In creasing the size of the woofer cone, on the other hand, will tend to raise the low-frequency cutoff unless efficiency is reduced or enclosure size in creased to compensate. By the same token, reducing the size of the woofer will diminish the enclosure volume required to achieve a given efficiency and low-frequency cutoff, at the expense of a lower maximum output level at the bottom end. So if you’re an organ or synthesizer buff seeking extremely deep bass, don’t assume that you will get it just by buying a speaker with a huge woofer. Depending on other design characteristics, that may actually work against you!
The number of drivers and their sizes are not, per se, indicators of quality in a speaker. Some excellent speakers, selling for several thousand dollars, have only a 6-inch cone driver and a small tweeter, for example. All else being equal (which it rarely is), a larger radiating surface will put out a greater quantity of bass, but there is, or should be, more than that to good sound.
A number of speakers now feature bipolar configuration. That involves having two identical sets of drivers, normally facing front and rear, which can produce a distinctive and pleasantly spacious sound quality. These speakers should be placed a few feet in front of a wall to produce the in tended effect, so they may require a larger room for best results. They are available over a wide range of prices from several manufacturers.
At this point, you may well ask "How do I go about making an intelligent selection from this confusing and overwhelming set of possibilities?" A good beginning would be to visit a dealer with a well-equipped demonstration room and present him with your problem. He should be able to make suggestions from any suitable brands that he carries. Have him demonstrate them, using electronic components that are comparable in price range and power ratings to your planned or present components. Take along some recordings, preferably on CD, with which you are thoroughly familiar. The reason for carrying your own recordings is to help you make comparisons of speakers in the store, Don't expect, however, that you can make a good comparison between speakers in the store and the ones you have at home without having them in the same place at the same time. You may be able to get a rough idea, but acoustic memory is surprisingly short. If you find speakers whose sound and price are to your liking, perhaps you can take them home for a trial. Alternatively, you may be able to buy them with an option to return for credit or refund. The ideal way to choose a new speaker (if you already have a functioning music system) is to corn pare it side by side, in your own home, with your older speakers, using your own familiar program material. Re member, the room dimensions, furnishings, and acoustic treatment have a profound effect on the sound.
If any of your possible choices are speakers that we have tested and re viewed in STEREO REVIEW, you can also use the published reports as a guide to making a selection. Almost any one we bother to review will be of at least average quality, and the list includes speakers spanning a wide range of size, price, and performance.
Even if the reviewed model is no longer available, as a general rule speaker manufacturers maintain their own standards carefully and apply the same basic principles of quality and performance across a product line.
Another obvious source of (some times) useful information and advice on speakers is from friends and acquaintances who happen to be audio enthusiasts. For example, if a friend's system sounds great to you, there is a good chance (though no guarantee) that it would do well in your home too. If his speakers are reasonably small and light, perhaps you could borrow them for a couple of hours. A less satisfactory alternative might be to take your CD's to his house and hear them on his equipment. Just bear in mind that the speakers may sound different in your own home.
A related question may arise in this sort of evaluation with regard to the contributions of the other components in the system. Suppose, for example, that your friend's amplifier is considerably more expensive than the one in your more plebeian system. If his sys tem is clearly better-sounding than yours, where does the credit go? To the speaker? To the amplifier? Possibly to the room itself or some other aspect of the system?
Now, I am not saying that there can not be sonic differences between amplifiers (although they are much less common than some would have you believe); the choice of amplifier may affect basic sound quality (that is, at levels below overload) in some rare instances. But the audible effects of the speaker/room portion of the system are so many orders of magnitude greater than those of any properly functioning amplifier that it would be foolish to look first to the amplifier as the source of any differences in sound quality, If space is limited, your choice will most likely have to be one of the many available compact speakers. Although we've all heard of the dyed-in-the wool audiophile who's stuffed a pair of large speakers, plus numerous electronic components, into a 9 x 12-foot room, it bears repeating that the only reason for a large enclosure is to hold the drivers that propagate the lower bass frequencies. If your musical tastes run to lighter fare, a well-dc-signed, well-made small speaker may meet all your needs.
Finally, keep in mind that nothing in life is perfect, and some compromise is always necessary. If your room is odd-shaped, and the speakers have to go in unorthodox places, don't be afraid to experiment. You might be pleasantly surprised with the results!
STEPPING UP TO SURROUND SOUND
One of the things anyone putting together a home theater system has to come to grips with is the need for quite a few speakers - at least four and preferably five, plus, possibly, a subwoofer Not only is there the question of how to fit them all in a room with out making it look like a hi-fi showroom, but also of making sure that they all work together well sonically. Here are some of the things you need to think about when selecting speakers for home theater.
PLACEMENT. Have a clear idea at the outset of where speakers must or can go. That will be dictated in large part by TV placement, since you will need left and right front speakers flanking it as symmetrically as possible and, ideally, a center speaker directly above or below it. Choosing speakers that won't fit that plan will cause problems.
Placement of the two surround speakers is somewhat more flexible, but they do need to be to the sides or rear of the listening position. The best location is often on the side walls some what above ear level, but that's by no means the only option.
Just remember that you want the surround speakers to disappear sonically as much as possible They should create a diffuse, enveloping sound field and not stand out as distinct, localizable sound sources. Usually that means you don t want them aiming directly at the listening position
MATCHING. Just as in two-channel stereo, the best results will be achieved if all the speakers in the system sound as much alike as possible. One way to achieve that is to use identical speakers all around. That's not always practical, however, and not necessarily desirable.
For example, you may need relatively large front left and right speakers to get adequate low-frequency extension and bass output but a relatively small center speaker to fit on top of the TV set And you probably will find it beneficial to have surround speakers with relatively diffuse radiation patterns, regardless of the front speakers Fortunately, manufacturers are making the choices easier by recognizing these potentially conflicting requirements and designing families of speakers to cope with them So if you don t go with identical speakers for all channels, narrow your shopping list to models from companies that design speakers of different sizes and configurations with the same "voicing' or tonal balance. The left and right front speakers should be the same, just as in a conventional stereo system.
Similarly the surrounds should be a pair of identical speakers not necessarily the same as the main front pair but having a similar tonal balance, especially through the midrange and treble (extended low frequency response is not necessary for the surrounds). Finally, the center speaker should match the tonal balance of the front left and right speakers as closely as possible down to at least 100 Hz. You want the sound across the front three speakers, especially, to be seamless.
And in most cases you will want the center speaker to be magnetically shielded to prevent color distortion when it is placed near a direct-view TV set BASS. Movie soundtracks often con tam substantially more energy in the bottom octave, between 20 and 40 Hz, than is commonly found in music (most music, in fact, doesn't go below about 50 Hz). That means that you may want more extended bass response in a home theater system than you would demand in one intended solely for music reproduction, and you will almost certainly have to be more concerned about low-frequency power-handling capacity. If you have front left and right speakers with good low-frequency Capability you can simply direct the bass for all channels to them. A more elegant and effective solution, however, is to add a subwoofer to the system and send all the deep bass to it in stead. Just be sure that you get a true subwoofer, capable of flat response down to at least 25 or 30 Hz. Not only will you get better bass performance, but you will also be free to use relatively compact main, center, and surround speakers.
MUSIC VS. MOVIES
People of ten assume that speakers that work well for home theater will not be suitable for music listening, or at least will not per form as well in that function as normal speakers Nothing could be further from the truth. The final acid test for any speakers you consider should be how they sound playing high quality music recordings. If they don't sound good on music, you can be sure that you could do better for soundtracks as well. The fundamental requirements -- smooth, extended response, even dispersion over the listening area, and low distortion -- are the same for both.
Source: Stereo Review (09-1995) - Michael Riggs