In a very basic sense, conventional speakers are simply a number of drivers (materials that vibrate to create sound waves) and a crossover (an electronic circuit that sends frequencies to the drivers) housed in some type of cabinet (generally a box-shaped casing made up of particle board, wood or veneer). The internal components of a speaker vibrate at a high rate of speed and convert electrical energy into physical motion.
Speakers vary wildly in size (from a small cube to a small refrigerator) and specifications. Unless you have some idea of what you want in a speaker, choosing the right one (or set) can be a nightmare. A few fundamentals, however, can assist in your quest for the perfect pair.
The internal components of a speaker include tweeters, midrange drivers, woofers and, in some models, powered subwoofers. Tweeters are small components that stop and start very quickly (moving back and forth over 20,000 times per second) to ensure that the sound being produced is vivid. Midrange drivers don't move as quickly as tweeters, but are responsible for moving larger masses of air. Woofers move even more air than midrange drivers to produce deep bass sounds. Many floor-standing speakers also include powered subwoofers that use a large driver to provide a great deal of power and a clean bass response. A speaker with a separate woofer and tweeter is referred to as a two-way system; one that adds a mid-range is a three-way system. A crossover network takes the audio signal and divides it up into different frequency ranges before it sends it to a tweeter or a woofer.
Types of Speakers
There are a number of different speaker types available on the market. The choices are as diverse as the wants and needs of electronics consumers.
Because of their compact size, bookshelf speakers are a good choice for consumers with a limited amount of space. They are placement friendly, and offer excellent midrange clarity for their rather modest price range. They sound best in smaller areas, but have a limited bass frequency range. The addition of a subwoofer can augment a bookshelf speaker's sound performance.
Sometimes referred to as tower speakers, floor-standing speakers move large amounts of air and offer greater dynamic range and bass performance than bookshelf models. Good floor-standing speakers can reproduce the lowest frequencies a human ear can hear and many models feature cabinet designs that minimize placement difficulties and visual impact. Placement can be more critical with floor-standing speakers. For best performance, it is recommended that they be positioned two to three inches from a wall.
Floor-standing speakers with built-in subwoofers
This is a new and increasingly popular model that offers the utmost in frequency range and response. The consolidated design eliminates the need to purchase separate subwoofers, and while not cheap, these speakers are often less expensive than purchasing separate components of similar quality.
Considered by many to be the best of both worlds, subwoofer/satellite systems combine the advantages of compact size with great sound. The speakers are small enough to be placed just about anywhere while the larger box (subwoofer section) can be placed out of sight. What's more, these systems produce vivid high and mid-range responses, as well as awesome bass results. Note: Some subwoofers used in these systems are woofers (not amplified), and don't reproduce the bass with authority. In this case, if your primary use is home theatre, you may want to consider an additional powered subwoofer.
When it comes to speakers, it can be painfully obvious that you get what you pay for. You can determine a quality speaker by its sound and in general, the better the sound, the higher the price tag. If you are purchasing speakers as part of a component system, evaluate their importance in your sound system. If you consider speakers a vital part of the sound system, it is recommended that you spend approximately 40 percent of your sound system budget on the speakers. Speakers generally range from under $100 to more than $1,000 a pair. (Quality bookshelf speakers can cost approximately $200 to $300 a pair and medium to large floor-standing speakers typically cost about $400 to $500 per pair.)
Consider These Important Features...
There are a number of things to consider (or listen for) when choosing speakers. Sound is of utmost importance, so listen carefully to the way a speaker sounds (two speakers with the same specifications can sound very different). When comparing speakers, bring your own music-you'll be more aware of familiar sounds-and play a few tunes that feature different acoustic sounds (bass, piano, guitar and vocals). Pay special attention to the different characteristics of the sound.
Disregard, for a moment, the specifications and listen to the depths to which the speaker reaches. Bass should sound powerful, but not distorted; it should be smooth and tight.
Most music lies in midrange, so make sure these tones are crisp and clear. This is where you want to compare different acoustics (vocals versus guitar strings, etc.).
Pay attention to the detail of the instruments. The highs should be smooth and warm, not shrill. Highs are also affected by external factors like carpeting, draperies and other furnishings so think about where the speakers will be and the affect your furnishings may have.
As you listen, walk around. Move away from the speakers and see if the quality diminishes. In general, better speakers sound the same from all points in a room. Adjust the volume. Does the clarity decrease as the volume increases? It shouldn't. Also, thump the speaker on the side of the cabinet with your fingers. A hollow sound may indicate poor quality in materials construction. A speaker's weight is also a good indication of materials and construction quality.