One of the biggest boons of the movie theater is its ability to make the viewer feel a part of the film. Home theaters have been moving closer and closer to replicating the cinema with larger and higher resolution TVs, but movies are more than simply the visuals. Adding a good surround sound system can take the viewer from simply watching video, to experiencing each film. In this feature, we'll talk about the basics of surround sound so you'll know what to buy, and what all the jargon means.

Audio Channels

One of the most frequent terms home theater buyers will hear are the channels available for a surround sound system. No, we're not talking TV channels, but instead unique channels of audio. Most speaker systems are described as the number of speakers with the number of subwoofers separated by a decimal point. Some of the most common speaker setups are 5.1 and 7.1 surround sound, but often times buyers could hear computer speakers with a subwoofer described as 2.1 speakers.

The designation, 5.1, 7.1, etc., defines how a system can work together, and is a simple way to start putting together a system. A 2.1 system is simply a left speaker, a right speaker and a subwoofer. A 4.1 system would add a front right, front left, rear right and rear left channels into the mix. With a 5.1 system, the setup adds a center channel. Lastly, a 7.1 system adds a center left and center right channel.

5.1 surround sound systems are the most commonly used systems and are the current cross section of best price and performance. More expensive 7.1 systems are becoming common on the high end, though we'd only recommend 7.1 systems to buyers prone to luxury. Instead, save the money from the 7.1 system and get a better TV to go with the amazing audio.

Output power

Output power for surround sound systems is measured in Watts. Depending on the size of the room and the size of the speakers, some home theater setups can get by on extremely low power, while larger rooms will obviously require more output. Small rooms and computer setups can likely get by with only 100 or so watts, though for medium sized rooms, we'd think about spending enough to get around 300-400 watts of sound. Don't purchase an entire system based on watts though. While it's important to keep in mind the range of watts needed, finding the right amount of inputs on a receiver, or a better quality speaker system will matter more than the raw amount of watts available. More watts equals more sound, but we'd always take quality over simple quantity.

Surround encoding

Marketers lay the buzzword sauce thickly on surround sound receivers, trying to confuse consumers about what each unit actually does. The main certification to check for is Dolby Digital support. Dolby Digital encoding, sometimes referred to as AC-3, has 5.1 channels of surround sound. Some HDTV broadcasts can take advantage of AC-3 encoding, pumping out full 5.1 surround sound to your living room. Blu-ray buyers might want to take note of a high end encoder called Dolby TrueHD. TrueHD has eight full range channels (for 7.1 surround) of sound.

THX is another bit of branding that will be attached to some devices. THX isn't an encoding standard, but rather a certification of quality. THX certified devices meet a specific set of criteria that aims to reproduce the highest quality audio. Any part of a home theater component can be THX certified, including speakers, drapes, and especially receivers.

Receiver

While we've gone in depth about which receiver to get in our feature on home theater cabling, we can reiterate some of the same buying guidelines. We recommend buyers find a future proof receiver that'll put out at least enough to power your current set of speakers. If you're like me and putting together your home theater a bit on the cheap, find a receiver that can move with you. In my case, that means I'm going to be looking for a home theater receiver that has five HDMI inputs, two or three analog inputs and has an output power of a few hundred watts. I expect in one to two years to hook all of my home theater equipment over HDMI exclusively, and since my HDTV only has two HDMI inputs, I expect to route most of my HDMI devices through my A/V receiver. I expect to spend around $500 when I finally throw down for my final receiver. Most buyers will be able to find a receiver for $300-$600 that does an adequate job for non-professional needs.

Now you're up to speed on surround sound basics, but do you need to know how to hook it all up? Be sure to check out our feature on hooking up a home theater. Oh, and if you don't yet have a TV, we've got a buying guide for HDTVs as well. Have some questions we didn't cover? Make sure to sound off in the comments.

[Images: William Hook, Jamil3.org]