Home theaters are all the rage now, and it wouldn't take much to build one in any home. Host Corey Greenberg, a technology expert, shows the hottest gear and latest technology for building a home theater.

Home theaters are dramatically changing the way we watch television these days. Big screens and big sound are becoming the number one choice for most consumers.

When talking about home theater, we mean the marriage of large-screen video and surround-sound audio. A home theater can be as simple as a big-screen television and basic surround sound in a family room, or a dedicated room designed with digital components, a dropdown screen and booming speakers throughout the room for an all-around movie theater experience.

No matter what type of home theater, it's first important to realize that we as a culture are moving into a digital age.

Analog vs. Digital

Analog is what we’ve had for years -- VHS, cassettes, and 8-tracks are all examples of analog, which sends electricity in the form of a continuous wave that reproduces the sound.

Digital formats -- DVDs and CDs -- send pulses of electricity that represent the zeros and ones that computers can understand. Digital has a lot of advantages, including the fact that it can record repeatedly with high quality and the diskettes don't tend to wear out like cassettes can.

Studio-size or megaplex?

For the best view, buy a television that's 27" or larger. Also, decide on a type of screen, and there are lots of choices:

• Plasma -- Plasma displays use more than a million tiny fluorescent picture tubes to make up the image. It gets its name because all fluorescent lights contain plasma. Plasma screens are flat, as small as 3" thick, which is a real advantage if space is a concern. Plasma screens can be pricey, costing from $4,000 to $10,000 depending on the size and quality. Plasma screens are also susceptible to "burn in," which means if a TV is left on a channel that has a static image on it for long periods of time, there is a risk of having the image permanently burned into your screen. For this reason, plasma screens are not recommended for video games.

• LCD -- This is another flat screen that's extremely popular right now. LCD stands for "liquid crystal display" and it uses the same technology as a laptop computer screen. These screens cost anywhere between $700 and $5,000, and they can be as slim as 2". There’s no danger of "burn in," and they have a long lifespan. But when compared to plasma screens, LCD screens do have their limitations. Many experts believe plasma has the better quality picture. It comes in larger sizes (up to 70" or 80" diagonally), while LCD is limited to approximately 50" now. Plasma has truer black levels, so you get better contrast and detail in the black, where LCD is a little grayer. LCD also has what's called a "slow refresh rate," which means if there is a fast moving object, the edges of it will appear blurred as it goes across the screen. In the smaller size screens, LCDs are wonderful sets -- great to put in the bathroom, kitchen or under a counter. The larger sizes are looking better all the time, and for some people they're fine, but a plasma screen would definitely be the ultimate choice.

A rear-projection television set is also an option. It's a classic big-screen TV, and there are three from which to choose:

• CRT -- This is the analog tube set we've had around for some time. This "Cathode Ray Tube" is relatively inexpensive, and the picture is considered the best of the rear-projection models. One major downside is that CRTs take up more space and need periodic maintenance.
  
• DLP -- "Digital Light Processing" screens have a chip with thousands of mirrors in it. The mirrors flip back and forth, reflecting the pixels onto the screen.
  
• LCD -- Discussed earlier, see above.

The next option is the high-end sports car of televisions:

A front-projection system just like what is in a real movie theater. Now there are several popular front-projection televisions on the market, and each uses a different technology to display the image, so the pros and cons vary. Front-projection DLP and LCD both offer superb picture quality, but their prices vary greatly -- from around $1,500 to $30,000 and up.

The high-end front-projection system is a CRT. They are used mainly in custom installations, and they cost anywhere from approximately $5,000 to $50,000 and up. The downside to CRT front-projection systems is that they are costly and require lots of maintenance. If a projector gets misaligned, even slightly, it will really affect the clarity of your image -- and will usually need the help of a professional installer to correct the problem.

No matter what type of projector you use, ambient light will wash out the picture. This means that a dark, dedicated room is needed to ensure the best picture quality. When choosing a screen for a front-projection system, you have two choices:

Non-perforated, which is less expensive.
Perforated, which has tiny holes that let sound pass through. This allows you to put speakers "behind" the screen.

Even after choosing the right TV technology for a home theater, there's still one decision to make. Since the advent of television, screens have had an almost square, 4x3 aspect ratio. But in recent years, widescreens have been introduced with a 16x9 image -- the native aspect ratio needed to best display high-definition television (HDTV). In fact, the colors pop off the screen. They're extremely vivid.

HDTV delivers twice the number of lines or resolution over standard analog TV, giving the picture great color and detail. Nearly all new widescreen televisions are HDTV compatible. Some cable and satellite boxes have HDTV tuners, or a separate outboard tuner can receive HDTV signals.

Although it will be more than five years before all television programming is in high definition, if planning to spend more than $500 on a TV, choose an HDTV-ready widescreen over the old standard screen size.

Finally, don't forget that there are new technologies coming out all the time.