Audio Speakers

Even though tweeters and woofers sound like something that should be coming out of a pet shop, they are the essential parts of a speaker. The woofer is the circular cone that emits sound from the mid-range down to the low frequencies, depending on how it is built. The tweeter handles the higher frequencies. It's smaller and usually has a dome shape. Larger speakers will often have more than one woofer to deliver a better range of sound. Subwoofers use large woofers to deliver very low-frequency sounds. Subwoofers are often stand-alone units, but they are sometimes built into tower speakers.

Many speakers will also be ported, where a hole or duct below the woofer is placed, thus opening the speaker enclosure to help the speaker extend bass. Other speakers (such as small satellites or on-walls) have acoustic suspension, meaning the enclosure is completely sealed.

Speaker spec sheets often cite the materials used to create them. What materials are better than others is difficult to say, because there are literally hundreds of material combinations used by different speaker manufacturers and the results are judged subjectively. For the novice buyer, the best thing to do is pick a number of speakers in your price range from different companies and listen to them at a local store. The best way to pick a speaker is to listen to it for yourself.

Subwoofers and Satellites

This is currently one of the most popular ways to buy speakers. Instead of mixing and matching model numbers, loudspeaker companies have created packages of speakers for 5.1 home theater configurations, combining a subwoofer with several satellite speakers. Since satellites are generally small and can't produce as much bass as a larger speaker, they need the subwoofer to fill in lower frequencies. Many satellite speakers feature creative modern designs, but don't go by looks alone. Always get a listen, if possible.

Bookshelf Speakers

Small satellites can be great, but if you really want to improve your listening experience, especially if you listen to a lot of music, you may want to go for a set of J bookshelf-sized speakers.

They can often produce a decent amount of their own bass, though it always helps to have a subwoofer for the most accurate sound. Bookshelf speakers generally have one woofer and a tweeter mounted into a wooden cabinet (usually made of a composite wood mate­rial called MDF) that has a veneered finish. They are also usually ported, which helps produce bass.

The Audio Basics

So you ve decided its time to upgrade from that boom box of yours to a real home audio system. While selecting a good system isnt as difficult as buying a car, there are many things to consider when creating a music and home theater experience thats right for you. Think of this as your step-by-step guide to better audio. The first thing you need to determine is what you want your audio system to do.

Home Theater

Standard home theater surround sound systems usually consist of a DVD player, an A/V receiver, two stereo speakers, one front center speaker, two rear surround speakers and a subwoofer. This is referred to as a 5.1 system (five speakers and one subwoofer). The receiver should be able to handle Dolby Digital encoded movies in order to deliver surround sound to all the speakers.

The main stereo speakers handle most of the action at the front of the room, while the center is used for the dialog. The rear speakers are used mostly for special effects, such as the sound of aireoplanes flying past the audience, while the subwoofer handles all the extreme low Frequency effects (LFE) such as explosions. Subwoofers can bring a lot of life into action and adventure movies.

Stereo

A basic stereo system consists of a source (usually a CD or DVD player, though every DVD player can play CD5), a stereo receiver or pre-amp and amplifier, and two speakers. Stereo systems with small speakers will usually need a subwoofer to handle the low frequencies, while full-range tower speakers can often handle all the audio frequencies by themselves.

Audio elitists prefer turntables and records to CD5, citing the warmth of analog over digital. A system with a turntable requires a special phono pre-amp, which can be purchased separately or built into a stereo receiver.

Audio Formats

Video may be whats on everyones mind when it comes to home theater, but audio shouldnt be forgotten. An A/V receiver that supports the right formats can turn an average home theater experience into a great home theater experience. At the core of this is surround Sound, which comes in several different flavors. Dolby is the de facto standard, while formats from DTS and SRS Labs offer some interesting alternatives. Several of these audio formats deliver the full home cinema experience DVD offers. A few of them even turn two-channel music into surround or create surround sound without the extra speakrs.
 

EX bolsters surround sound by adding a channel, often referred to as the rear or back channel. But the DVD has to be encoded with EX as well to get the full experience. Receivers supporting EX are referred to as 6.1 receivers or even 7.1 receivers because they split the back channel into two speakers,

Pro Logic was the preferred method of achieving surround sound before the advent of Dolby Digital. Pro Logic II is an extension of its father format and is able to take two-channel audio (CDs, MP3s, broadcast TV or VHS tapes) and turn it into 5.1 audio. A further version called Dolby Pro Logic llx does the same thing but turns it into 6.1 or even 7.1 audio. It can also take 5.1 and add a rear channel, though it wont be as complete as a true 6.1-encoded soundtrack.

This technology creates 5.1 where only two speakers are present. This is not true 5.1, but rather, a psychoacoustic method of tricking the ears into thinking sound is coming from all around them, rather than just in front. Sometimes this is called virtual surround sound. A similar version of this technology, called Dolby Headphone, works on headphones.

DTS, method of creating 5.1 surround sound. It claims to offer a higher quality 5.1 soundtrack by correcting what the company sees to be inconsistencies in standard 5.1 decoding. It can be found on many DVD, game and audio titles, as well as A/V components, but it is still considered and optional format.