Twenty five years ago, only a small percentage of households in the United States had cable television, and VCRs were a brand-new luxury item. Sound systems, for the most part, were limited to the small speaker built into the television, and not many people had a screen larger than 27 inches. There was certainly no mistaking the typical TV room for a home theater -- home theaters were expensive setups with actual film projectors and wide screens.
A custom-installed home theater system
Over the years, the world of home entertainment has changed radically. These days, most U.S. households get at least 50 channels and have a good-sized color television and a VCR. More and more people are adding additional advanced components to their entertainment setup to create home theater systems. The world of home entertainment is changing rapidly, and consumers have a wide range of options.
Now, we'll look at home theater systems to find out what they are, what they can do, and what components you need to set one up. If you're thinking of turning your den into a fully functioning home theater, this article will help you get started.
What is Home Theater?
Home theater is difficult to define -- it's really just a vague term for a particular approach to home entertainment. Generally speaking, a home theater system is a combination of electronic components designed to recreate the experience of watching a movie in a theater. When you watch a movie on a home theater system, you are more immersed in the experience than when you watch one on an ordinary television.
To see how home theaters do this, let's first look at the original model -- the movie theater. People have had VCRs in their homes for years, and in the United States, there are video rental stores everywhere. So why do we keep spending so much money going to the movie theater if we can watch the movie in our own home for so much cheaper? We go because the theater offers us an amazing experience we just don't get at home. There are a few main components that make watching TV and going to the movies very different.
The basic idea of a home theater is to recreate these elements with home equipment. In the next section, we'll look at an overview of what you need to get started.
- One of the biggest differences is the sound experience. When you go to see a movie in a quality movie theater, you'll hear the music, sound effects and dialogue not just from the screen, but all around you. If you've read How Movie Sound Works, you know that a standard movie theater has three speakers behind the screen -- one to the right, one to the left and one in the center -- and several other speakers spread out in the rest of the theater.
In this surround sound system, you hear different parts of the soundtrack coming from different places. When somebody on the left side of the screen says something, you hear it more from the left speaker. And in a movie like "Star Wars", you hear a rumbling swoosh travel from the front of the theater to the rear as a spaceship flies toward the camera and off the screen. You are more involved in the experience of watching a film because the world of the movie is all around you.
- The second chief component of the theater experience is the large size of the movie screen. In a theater, the screen takes up most of your field of view, which makes it very easy to lose yourself in the movie. After all, you're sitting in the dark with only one thing to look at, and everything you're looking at seems much bigger than life.
- We also enjoy going to the movies because we can see everything so well. Film projectors present very large, clear pictures. The detail is much sharper than what we see on an ordinary 19-inch television, and the movement is much more fluid. We may not consciously recognize this, but it does make a significant difference in how we enjoy a movie. When we can see more detail, we are more engrossed in the world of the movie.
What Do You Need?
In the last section, we saw that the major components of a movie-theater experience are a large, clear picture and a surround-sound system. To build a home theater, then, you need to recreate these elements. At the bare minimum, you need:
And, of course, you'll need a room where you can arrange all this stuff.
- A large-screen television (at least 27 inches across, measured diagonally) with a clear picture
- At least four speakers
- Equipment for splitting up the surround-sound signal and sending it to the speakers
- Something that plays or broadcasts movies in surround sound, preferably with a clear picture
There are any number of ways you can meet this criteria. In the end, your home theater system depends on how much money you're willing to spend and how important certain areas of performance are to you.
Photo courtesy Sony
One home theater option is a "home theater in a box" system. This one from Sony consists of a DVD player with built-in surround-sound receiver and a collection of speakers.
If you're not looking to spend much money, and already have a good-sized television and a stereo system, you can upgrade your entertainment system into a fairly crude home theater with a couple of extra speakers and a few other inexpensive components (click here to find out how). If you invest in a basic surround-sound system and a new DVD player, you might spend $500. For a more advanced system, with a larger television and an advanced sound system, you might spend as much as $8,000. For $30,000, you could set up a real theater, with a projection television, built-in speakers and bolted theater seats (and maybe a concession stand).
In the following sections, we'll look at the different options for televisions, surround-sound receivers, speakers, and video sources. We'll find out the advantages and disadvantages of different types of equipment, as well as the price range and long-term benefits. We'll also look at some of the extra components you can add to put the finishing touches on your home theater system.
The main thing that sets a home theater apart from an ordinary television setup is the surround sound. For a proper surround-sound system, you need two to three speakers in front of you and two to three speakers to your sides or behind you. The audio signal is split into multiple channels so that different sound information comes out of the various speakers.
The most prominent sounds come out of the front speakers. When someone or something is making noise on the left side of the screen, you hear it more from a speaker to the left of the screen. When something is happening on the right, you hear it more from a speaker to the right of the screen.
The third speaker sits in the center, just under or above the screen. This center speaker is very important because it anchors the sound coming from the left and right speakers -- it plays all the dialogue and front sound effects so that they seem to be coming from the center of your television screen, rather than from the sides.
The speakers behind you fill in various sorts of background noise in the movie -- dogs barking, rushing water, the sound of a plane overhead. They also work with the speakers in front of you to give the sensation of movement -- a sound starts from the front and then moves behind you.
But how do all these sounds get split up? This is the job of the audio/video receiver, which is the real heart of a home theater. In the next section, we'll see what this component does.
The audio/video receiver and amplifier assembly in a home theater does the same job as the receiver and amplifier assembly in any stereo system: It receives signals from various input devices -- a VCR, DVD player, satellite dish, etc. -- interprets and amplifies those signals and then sends them to output devices -- your television and sound system.
Photo courtesy Sony
A surround-sound stereo receiver from Sony
A home theater audio/video receiver and amplifier assembly actually combines several different components. You can generally assemble a superior home theater system by buying the components separately, but most people buy one unit that does all these jobs because it is more cost effective.
The different components are:
The path of the audio and video is pretty straightforward. The source component (DVD player, VCR, etc.) feeds a signal to the receiver unit. You choose which input component you want to feed to your output unit, and the preamplifier selects this signal and amplifies its line level a little bit.
- Audio/video inputs for video sources (DVD player, VCR)
- Surround-sound decoder (aka signal processor)
- Power amplifiers for each sound channel
- Outputs for speakers and television
The receiver is at the heart of a typical home theater system.
If you've selected, say, a VCR, the receiver sends the video onto your television and sends the audio to the decoder. The decoder sorts out the different sound channels from the VHS signal, and then sends the information to amplifiers for each sound-channel output. These amplifiers are connected to the appropriate speaker or speakers.
Digital decoders and analog decoders handle the job differently. Digital surround sound is quite simple: When a company is producing a Dolby Digital® program, for example, they encode six separate audio channels, specifically balanced for a Dolby Digital speaker setup. A Dolby Digital surround-sound decoder recognizes these different channels and sends them to the appropriate speakers.
Analog surround sound is something else altogether. It turns out that the different analog surround-sound channels are actually extracted from the two standard audio channels that make up any ordinary stereo signal. This is commonly called 4-2-4 processing because the encoder essentially takes the rear and front channels and works them into the ordinary stereo channels, and a surround-sound decoder separates the four channels out again. See How Surround Sound Works for more information.
There are a wide range of audio/video receivers available. These receivers are often sold with all the speakers you need, as a complete home theater system. These systems run as low as $250 and as high as $1,500.
One of the most important differences between audio/video receiver models is what surround-sound formats they support. In the next section, we'll find out what the different formats are and see what they offer.
Which Surround-Sound Format?
In the last section, we saw that audio/video receivers decode the surround sound information encoded in video signals and drive the appropriate speakers. Different audio/video receivers are equipped to decode different formats. Today, there are five home theater surround-sound formats in general use:
- Dolby Surround Sound®/Do It Yourself
The most basic type of surround-sound system splits a standard stereo signal into three separate channels -- left and right front stereo and rear surround sound. Typically, you connect two rear speakers, both playing the same rear channel. To find out how to hook up a basic version of this system using a stereo receiver, check out this page.
- Dolby Pro Logic®
With five speakers and only four channels, Dolby Pro Logic is also a fairly basic format. The system has separate channels powering a central front speaker and left and right front speakers. A Pro Logic system also has two rear speakers, but both play the same channel. Pro Logic gives you rich stereo sound in front and a general sensation of noise behind you. This is the surround-sound format used in all standard cable and broadcast television and VHS video. Many digital satellite broadcasts also use this format, and it is an option on most DVDs.
- Dolby Digital®
For a richer sound, with more channels, most DVDs and some digital satellite broadcasts use the Dolby Digital format . The main difference between Pro Logic and Dolby Digital is that Dolby Digital has two separate rear speaker channels, as well as a subwoofer channel (the full name of the format is Dolby Digital 5.1, indicating five ordinary channels and one "effects" channel). The two rear speakers are positioned to the right and left of the listener, rather than behind the listener, to give a more precise surround effect. The subwoofer channel carries low-frequency sound to give a bass boost and create a rumbling effect for certain special effects sounds, such as explosions and trains.
Another significant difference between the formats is that Dolby Digital is transmitted as a digital signal, like CDs, rather than an analog signal, like a VHS video track. This makes for a clearer, richer sound, with less unwanted speaker noise. Dolby Digital is in limited broadcast right now, but it is the standard format for HDTV, which means it may be the most popular sound format in the future.
- Dolby Digital EX®
This format is pretty much the same thing as Dolby Digital 5.1, except it includes a sixth sound channel for a speaker positioned right behind the listener. This speaker serves the same function as the front central speaker -- it anchors the left and right speakers. The sixth channel works a little differently than the other five: The EX receiver extracts a signal from the rear left and right channels. At this time, Dolby Digital EX is not used widely, but in the future more DVDs and digital broadcasts will likely take advantage of its expanded surround-sound capabilities
Typically, receivers with Dolby Digital decoders cost more than ones with only Dolby Pro Logic decoders, and Dolby Digital EX units cost a little bit more. Many Dolby Digital units also recognize DTS, but this shouldn't be a big concern because the few movies that are encoded with a DTS track are generally encoded with a Dolby Digital track as well. All Dolby Digital units also recognize Dolby Pro Logic, and all Dolby Digital EX units recognize standard Dolby Digital as well as Pro Logic. Most DVD players have built-in surround sound decoders for multiple formats.
- Digital Theater Sound® (DTS)
Home theater DTS is based on the DTS system you'll find in many movie theaters. The home version, an alternative format that works the same basic way as Dolby Digital, is not in widespread use. This is simply because Dolby Pro Logic and Dolby Digital have been accepted as the standard surround formats, so broadcasts, videos and DVDs are usually encoded in one of these formats rather than DTS. The format is slightly superior to Dolby Digital in that it compresses the signal to a lesser degree, which translates to better sound; but for most people, the difference is negligible. There is also DTS ES, a DTS format that adds an extra rear channel, just like Dolby Digital EX.
The cheapest receiver units will only have Pro Logic capabilities. If you're used to watching television using your television set's speaker, or even in stereo, you may be satisfied with a Pro Logic system. If you want superior surround sound, however, you should go with a Dolby Digital system. This is definitely a good investment, since Dolby Digital is already the standard format for DVDs and will soon be the norm for television broadcasts. If you're looking even further into the future, consider getting a Dolby Digital EX unit for a fuller surround-sound experience.
The sound system is what really makes a home theater experience complete, but the first thing you'll probably notice when you sit down in front of a theater setup is the television. In the next few sections, we'll see how televisions fit into the home theater.
Standard Direct-View Television
The biggest variable in home theater systems is the television. You can go with a large-screen direct-view television and spend as little as $300, or you can spring for a front-projection television, which could cost you $7,000 or more. The main factors that determine television price are size and picture resolution. Another important consideration is digital capacity and signal format.
Direct-view televisions are the sets that we're all familiar with. They have a cathode ray tube (CRT), with a scanning electron gun that paints the picture on a phosphor-coated screen and a tuner that picks up broadcast signals. Good direct-view televisions deliver an excellent picture, but because of the tube technology, they are limited in size. The biggest direct-view television screen you can get these days measures 40 inches across (diagonally).
Photo courtesy Sony
A 32-inch direct-view television from Sony: A direct-view television is certainly adequate for a simpler home theater system.
This is a pretty big picture, of course, and will work well in a basic home theater setup. You might even be content with a 27-inch model. The general rule for television size is that you want a screen that measures about one-third your distance from the screen (if you sit 9 feet from the screen, a 36-inch television screen would be perfect). These are the guidelines for standard televisions, because if your screen is bigger, or you sit closer, the scan lines that make up the picture will seem fairly large, which translates to a lower resolution. This is inherent in the standard television signal -- it has a set number of vertical lines of resolution -- the number of horizontal lines in one screen -- no matter how big your screen is. High-definition television (HDTV) has more vertical lines of resolution, so you'll be able to sit closer and still see a clear picture when watching HDTV-formatted video.
Photo courtesy Sony
With a 40-inch screen, the Sony Wega is at the upper limit of direct-view televisions.
When you're shopping for direct-view televisions, pay attention to image contrast. A television with a darker screen will give you a better picture because there will be a stronger contrast between light and dark -- black will actually appear black, rather than gray. You should also look for a television with a flatter screen. If the tube is more curved, the picture will be more distorted and you'll see more glare from other light sources. A perfectly flat screen will usually give you the best picture.
If you need a very large television, you'll probably need a projection television. In the next couple of sections, we'll see what the standard projection technologies have to offer.
If a very large screen size is important to you, look into rear-projection televisions. These sets don't have the same size constraints as direct-view televisions because they don't use the cathode ray tube for the display. Instead, they use a projection screen. Projection televisions actually use three different cathode ray tubes that split up the video signal into three different colors -- red, green and blue. The different combinations of these colors of light can produce the entire visual spectrum. Inside the television, the three CRTs project onto a mirror, which bounces the full-color image up to a screen.
Photo courtesy Sony
A 53-inch widescreen rear-projection television from Sony
The advantage of these televisions is that you can get a very large picture for a relatively low price. For example, you can get a 45-inch screen for less than $1,500. When these sets were first introduced, there were some major drawbacks -- the picture had a fairly low resolution, and it wasn't nearly as bright as a direct-view set. Recent rear-projection models have largely overcome these shortcomings, approaching the picture quality of direct-view televisions.
Some rear-projection sets may have a smaller viewing angle that direct view sets. No matter where you sit in front of a direct-view television, the screen maintains the same picture quality. If you look at a rear-projection screen from an extreme angle, the picture may be much darker and you won't be able to see what's happening in the movie. Newer projection sets use high-quality screens that work well from most angles, but older sets may have a fairly narrow viewing area.
If you're looking to buy a rear-projection television, the main things to compare are cathode-ray-tube size and design and screen quality. Larger CRTs will project a better picture, and glass lenses work better than plastic ones. Even a top-notch picture from the CRTs can look muddy on a bad projection screen, so be sure to pay attention to screen material. Darker screens are better because they present an image with better light-and-dark contrast. You should also look for a screen made of glare-resistant material.
Standard front-projection televisions work in pretty much the same way as rear-projection televisions, but the system is not contained in a television case. They are set up more like a film projector -- the three CRT projectors are combined in one unit, and you center the television image on a separate fabric screen.
Photo courtesy Newstream
A high-end digital front projector from Sharp
The main advantage of a front-projection television is very large screen size. Since the components don't have to be packaged together, screen size is limited mainly by the room space -- what size screen can you fit in the theater, and how much distance can you put between the projector and the screen. Screens as wide as 200 inches are not uncommon. Projectors do vary in capacity -- make sure the projector is powerful enough to project a bright image across the room.
One drawback of front-projection televisions is that they are very difficult to install, and they may require extensive maintenance. You have to mount them to the floor or ceiling at the right distance from the screen. For standard CRT models, you also have to align the different CRTs so that the different color pictures are lined up exactly. Otherwise, the images in your picture will have a color fringe around the edges. Usually, you need a professional to install the unit properly.
Another drawback is they only work properly in a darkened room. Consequently, they are really only suitable for a separate home theater space, rather than a family room or ordinary den. Since they are designed for watching movies, front projectors don't usually have a built-in television tuner: They don't receive television signals themselves, so they must be hooked up to a separate tuner (such as the tuner in a VCR).
In recent years, several new front-projection technologies have hit the market. Liquid crystal display systems have only one projector and lens, so you don't have to bother with configuring the different colors. These units generate the video picture on an LCD screen, and then project this image. This makes it much easier to set up your system.
Another system, the light-valve projector, combines CRTs and LCDs. These projectors use three CRTs and three LCD screens. They project the three LCD pictures on the screen, just like a CRT projector. By combining the two technologies, these units project a clearer picture than either CRT or LCD models. The drawback is that these units are much more expensive -- you can get a CRT or LCD projector for $5,000 to $6,000, but you can expect to pay at least $15,000 for a light-valve model.
The most advanced technologies are digital micro-mirror device and digital light processing projectors. These two designs generate pictures by manipulating a panel of thousands of tiny, sensitive mirrors. The individual mirrors act as pixels for different colors -- the system creates different pictures by turning some mirrors on and some mirrors off. These designs project the clearest, brightest pictures of the bunch. Like light-valve projectors, they are significantly more expensive than CRT and LCD units, starting at about $10,000.
The most recent addition to the world of televisions is plasma flat-screen technology. These televisions don't have CRTs or projector devices, so they have extremely thin designs. The typical plasma screen is less than 6 inches deep. These televisions are also very light, so it's fairly easy to mount one on your wall. If you plan to set up a home theater in a smaller room, this is a definite plus -- you don't have to worry about hauling a giant direct-view or rear-projection model in, and you don't need to figure out where to position a projector.
Photo courtesy Sony
A flat-panel plasma television from Sony
Plasma televisions create pictures with an array of cells that receive a constant flow of low-pressure neon and xenon gas. The cells are arranged in a matrix between sheets of thin glass and are covered with electrodes. When an electrode applies a charge to a particular cell, the voltage ignites the gas, changing it to plasma, which emits ultraviolet (UV) light. The UV light activates colored phosphors on another layer, and the phosphors emit visible colored light (this is the same basic process that occurs in a fluorescent lamp).
Each cell is dedicated to a particular color -- red, green or blue. Each pixel, the individual dots that make up a television image, has three different cells, one for each color.
Plasma displays offer great picture quality, but not always the best. They may take the lead as the preferred future technology, but at this point their performance advantages may not justify the price, which is upwards of $6,000. The real benefit of a flat plasma screen is its compact size, and if you have a small theater space, this may be reason enough to shell out the extra money.
Digital or Analog Television?
In addition to the television technology options, you also have to consider signal format when building your home theater.
For most of the history of television, there was only one kind of video signal -- analog. If you've read How Analog-Digital Recording Works, then you know that analog signals travel as a constant stream of information. In the case of video, the analog signal contains a stream of information telling the television's electron gun how to paint lines on the phosphor screen. The problem with this sort of signal is that it degrades easily -- when you transmit video, you lose some of the picture quality of the original.
Over the past 10 years, digital television has taken its place alongside analog television. Digital video signals consist of bits of data, that is, sets of 1s and 0s. The advantage of sending information this way is that it can't degrade -- each bit has a set "either-or" value, so the signal will be exactly the same after transmission. Because they translate visual information so exactly, digital signals can carry much more detail than analog signals. Digital televisions, therefore, have superior picture quality.
At this time, there are a number of different digital formats, with varying levels of picture quality. A standard-definition television (SDTV) signal uses 480 horizontal scan lines of picture information, the same number as standard television in the United States. These have increased picture quality simply because the signal isn't degraded in transmission. The more impressive digital format is high-definition television (HDTV), which boasts many more scan lines of picture information. There are two different types of HDTV signals -- one uses 720 lines and the other uses 1,080 lines.
Another advantage of some digital signals is that they are progressively scanned. If you've read How Television Works, then you know that a traditional television's electron gun paints only half of the picture lines in every pass. Television was developed this way because of technological constraints -- originally the electron gun couldn't move fast enough to paint the whole screen in one pass. So the standard television signal is actually interlaced: It sends two fields -- the odd picture lines and then the even ones -- for every full frame.
We've long since overcome the technological constraints that made this system necessary, but we've been stuck with this way of displaying a picture because it is actually built into the standard television format. Digital video formats that feature progressive scanning paint the entire frame with one pass, which improves the fluidity of movement in a picture.
HDTV sets, and some SDTV models, also feature an impressive widescreen display. Traditional television has an aspect ratio of 4:3. This simply means that if the screen is four units wide, it's three units high. Another way to say this is that it is four-thirds, or 1.33, times as wide as it is high. HDTV screens have a 16:9, or 1.78:1, aspect ratio, meaning that the screen is 1.78 times as wide as it is high. This shape is closer to the wide aspect ratio of theatrical movies, and so is a definite plus for a home theater system. For more information about the advantages of a wider screen, check out How Video Formatting Works.
So HDTV has a lot of advantages, but HDTV sets also have a higher price tag. Right now, you can expect to pay $1,200 to $4,000 for an HDTV direct-view or rear-projection set, and $10,000 to $20,000 for an HDTV front-projection set. If you're on the fence, one thing that might tip the scales in favor of an HDTV set is the future of television. The U.S. government plans for HDTV to be the standard television format at some point in the near future; so, while HDTV is a high-end luxury today, it may eventually be the standard format.
Another option is to get an HDTV-ready television. These sets, which have the standard 4:3 aspect ratio, have the necessary resolution capabilities to display an HDTV picture, but don't have the necessary decoder to interpret the HDTV signal. Out of the box, they function just like traditional televisions. But you can by a separate HDTV decoder that upgrades them to display HDTV broadcasts (either cropped or letterbox to fit the narrow screen size).
These televisions cost a lot less than true HDTV sets, so they are a good option if you don't want a television that will be outdated in ten years but you don't want to spend the extra money for an HDTV set. For more information about HDTV and digital television, check out How HDTV Works.
To put a home theater system to work, you obviously need some way to watch movies or TV shows. To get the most out of your giant television and sophisticated sound equipment, you need a high-quality signal. In the next few sections, we'll look at the various video-source options.
The simplest home theater video source is the VCR. VCRs are amazing machines, and the library of movies available on VHS video tape is overwhelming. The huge popularity of the format is a real testament to its functionality and ability. When they first came on the scene, VCRs completely revolutionized the home-entertainment industry.
These days, however, VCRs are outdone by most other available technologies. VHS picture quality is much lower than DVD -- 240 lines of horizontal resolution vs. 500 lines. Even standard broadcast television signals carry a higher-resolution picture. There's only so much you can record onto 0.5-inch VHS tape.
While your VCR does just fine playing movies on a 19-inch television, its shortcomings are more obvious when you play a movie on a top-of-the-line home theater system. If you don't have a hi-fi stereo VCR, you'll really notice the difference. The cheapest VCRs generally have mono sound, meaning they feed a single audio track along with the video picture. There's no reason to hook this sort of VCR up to a home theater sound system -- you'll only get sound out of one of your front speakers, or the same soundtrack out of multiple speakers.
A hi-fi stereo VCR, which doesn't cost much more than a mono VCR, will vastly improve the way your home theater plays video tapes. You'll still have the low resolution, but if a video is recorded with Dolby Surround Sound (and most feature films made after 1980 are), you'll get the full home theater sound experience.
While a VCR won't give you the best picture quality, it's certainly an important part of a home theater system, if only because there are so many movies available on VHS video. Eventually, VHS will be completely replaced by digital video formats like DVD, but for the immediate future, VCRs are standard home entertainment equipment.
DVD Players and Digital Movie Recorders
DVDs (digital versatile discs) have really taken off in the past five years. They offer excellent picture quality and very clear, rich sound. Most DVDs are formatted for one or more surround-sound formats, and you can find a wide selection of widescreen DVDs, discs that present the movie in its original theatrical shape (see How Video Formatting Works for more details). Additionally, DVDs often have a number of extra features for the movie fan, such as original theatrical trailers, audio commentary tracks and special documentaries
All of these qualities make DVDs an ideal technology for home theater -- they make full use of all that high-end technology. If you've already invested in a surround-sound system and a big-screen TV, you should definitely pick up a DVD player. The players are relatively inexpensive -- you can get a basic model for less than $200 -- and the format is rapidly gaining acceptance, with more and more DVD movies being released every month. DVDs have already taken the place of laser discs, and will eventually take the place of VHS tapes. In the near future, DVD players will probably be as common as VCRs.
At this time, most DVD players do lack one of the most useful capabilities of a VCR -- they can't record video; they can only play it. There are a few DVD recorders on the market, but these run upwards of $1,000.
So, should you go ahead and get a DVD player or wait for DVD recorders to drop in price? As with any home electronics, it's largely a guessing game of when the current DVD players will be outdated. It may take a while for DVD recorders to become standard equipment, and when they do, you can expect them to be much more expensive than ordinary players. So, if you're already putting a home entertainment system together, you would probably do best to go ahead and pick up a standard DVD player.
If you record a lot of programming off television so you can watch it later, you might want to supplement your DVD player with a digital video recorder (DVR). Unlike VCRs, DVRs store video in digital form, on a hard drive.
Actually, when you hook up a digital video recorder -- such as a TiVo unit -- all programming is recorded on a hard drive, and then sent onto your television set a few seconds later. This means that you can pause a "live program" -- a program being broadcast at that time -- and start watching it where you left off. These units don't provide the programming -- you have to connect another video source, like a cable outlet or satellite dish. You also have to connect the unit to a phone line -- it makes a daily call to update its programming information.
DVRs are superior to VCRs in some ways and inferior in others. They can record programming with much better picture quality, but there's no way to archive what you've recorded -- eventually, you'll run out of hard-disk space. You can, however, record the video from the DVR to your VCR, and archive your favorite programs that way.
One nice feature of DVRs is that when you record television programs, you only have to enter the program name, not the time that it's on. The service's programming information will also help you find programs you like, skip commercials when you record, and record your favorite shows every week.
For more information on DVD players and DVD technology, check out our comprehensive How DVDs and DVD Players Work.
Television Reception Options
Home theaters aren't just for tapes and DVDs, of course. You'll also want to watch television. These days, you have a number of options to choose from.
In the United States, the most popular options are broadcast television (the signals you can pick up with a rabbit-ear antenna) and cable television. Broadcast and standard cable signals both transmit video with 330 lines of horizontal resolution. This is better than VHS video, but not as good as DVD or digital television. Standard cable and broadcast TV also feature programming with Dolby Pro Logic surround sound, but they cannot carry Dolby Digital.
The main advantage of both broadcast and cable is price -- broadcast is free, and cable is generally less expensive than satellite programming. Additionally, cable and broadcast always carry local stations, while satellite service may not.
If you want to get the maximum use out of your home entertainment system while you're watching television, you should consider getting a direct satellite system, such as DIRECTV or EchoStar. To get satellite programming, you need to buy and install a satellite dish, hook the receiver up to your entertainment system, and then pay the monthly fees, just as with ordinary cable.
Right now, the main advantage of a satellite system is that you get a better, digital picture (near the level of DVD). Most satellite programming still uses Dolby Pro Logic surround sound, but providers will use Dolby Digital more in the future. HDTV broadcasting is also limited at this point, but it is on the rise. When shopping for a satellite system, be sure you get one that can do everything you want. At this time, you need a larger, more expensive satellite dish to pick up HDTV programming, and you may need a special system to pick up local stations.
Another option is digital cable. Digital cable comes into your house via lines, just like standard cable, but it carries a better quality picture (the level of quality varies depending on the provider). To learn more about cable and digital cable, check out How Cable Television Works.
One of the most important components in a home theater system is the speakers. Even with a top-of-the-line DVD player and audio/video receiver, the sound quality will be terrible if you don't have good speakers. In the next section, we'll find out about these essential components.
Speakers vary a great deal in performance, as well as price. The main rule in shopping for speakers, whether for a home theater or your stereo system, is to try the speakers out in the store and decide what sounds good to you. To find out about the different rankings of speakers, check out this page.
Photo courtesy Sony
A Sony micro speaker
For your home theater system, you will need five standard speakers (or six, if you're putting together a Dolby Digital Ex system) and an optional subwoofer speaker for bass sounds. Ideally, you'll want to get five (or six) identical speakers, to insure rich sound from all sides, but this might not be feasible, depending on your theater space and budget. If you're looking to save money, you could even use your television's built-in speaker as the central front unit, but it won't give you the best results. Different speaker models handle sound differently, creating an unbalanced surround effect. To get theater-quality effects, you should get three identical, full-size front speakers.
The main full-size speaker options are floor-standing units, bookshelf units and in-wall units. Floor standing units are the largest, and they generally have the highest performance levels, as well as the highest price tags. Bookshelf units and in-wall units are more compact, which is great if space is limited, and they perform very well. They may lack some bass range, but a good subwoofer should adequately compensate for this.
Photo courtesy Sony
In-wall speakers from Sony
Many home theater systems use more compact, generally less-expensive speakers for the two rear surround channels. This will usually give you fine results, and is often the best solution if you don't have space for full-size speakers in your theater room. Some people even prefer these smaller bipole and dipole speakers because they generate sound in multiple directions, giving a more diffused sound.
Another thing to think about is the speaker technology. You may want to consider electrostatic speakers or planar magnetic speakers instead of the conventional dynamic driver design. See How Speakers Work to learn more about these different technologies.
Photo courtesy Sony
A digital subwoofer from Sony
To make it easier to assemble a home theater system, many manufacturers have put together home theater speaker packages, putting front and rear speakers together in a set. These packages vary in price and quality, so you should give them a "test drive" before you buy, just as you would with individual speakers.
If price is no object when you're putting together a home theater system, you might want to consider THX certification. In the next section, we'll find out what the THX system is all about.
If you want a top-notch home theater, look into a THX®-certified system. If you've read How THX Works, then you know that THX is Lucasfilm's set of standards for movie-theater equipment and arrangement. Lucasfilm has also come up with certification standards for home theater setup, and if you want the best of the best, this is the way to go. The chief aim of Home THX standards is to ensure the highest-quality re-creation of actual theater sound.
There are currently two THX standards: THX Select, created with a 2,000-cubic-foot (57-cubic-meter) room in mind, and THX Ultra, for spaces with over 3,000 cubic feet (85 cubic meters). THX has worked with electronics manufacturers to create equipment that lives up to the THX standards. THX has certified:
A THX-certified home theater will cost you a good bit more than an ordinary home theater, because THX-certified components are mainly top-of-the-line equipment. If you just want a superior entertainment system in your home, you don't need to worry about THX systems. This sort of system is a luxury purchase, for connoisseurs driven to get the best possible sound out of their systems, or for folks with money to burn.
- Audio/video receivers
- DVD players
- Video screens - rated by their effect on acoustics
To find out more about THX home theater standards, check out the THX Web site.
Putting It All Together
Once you have all the components, it's time to set up the theater space. There are several factors to keep in mind when choosing and arranging the home theater room.
First of all, consider the architecture of the room. A home theater should be something like a movie theater -- you want an enclosed, rectangular room, with a good amount of space and not too much outside light. You need an enclosed space to get the best sound quality -- open rooms don't have ideal acoustics. If you are building a top-of-the-line theater, you may want curtained walls. This soft surface cuts down on disruptive echoes. For the same reason, it is generally better to have a carpeted floor than a wood or linoleum floor.
Once you've decided what room to use, you need to figure out where to put everything. To find the best position for the television, just use common sense. It should be easily visible -- you don't want to crane your neck -- and it shouldn't be in a place that gets a lot of glare from outside. Put the television wherever it seems most logical, and build your system around that.
Getting the sound system in place is a bit more complicated. You should set the three front speakers up so that they are spaced evenly, all at about the same height. Also, make sure they are near the level of the television screen so that the sound seems to be coming from the action and actors you're watching on the TV. The idea is to that you shouldn't be made aware of the speakers when you watch a movie -- your attention should be on the movie.
You have a couple of different options for arranging the rear speakers. Dolby Digital is designed for speakers positioned to either side of the listener, while Dolby Pro Logic systems should have the rear speakers behind the listener. In any case, the rear speakers should be mounted at the same height, spaced an equal distance from the listener. Of course, chances are you'll have more than one listener, so the spacing won't be equal for everybody. You can find the central listening position -- such as the middle of the couch -- and space everything according to that point, while still paying attention to other seats in the room.
It doesn't matter so much where you put your subwoofer. The low frequencies aren't directional like the higher frequencies emitted by the main speakers, so it can really go anywhere in the room. For the best rumbling effect, however, you should put the subwoofer on the floor or against a wall -- this will help the low frequencies carry through the room.
Another thing to consider in your home theater is lighting. It's important that you don't have a lot of bright ambient light in the room, because this may cause glare on the screen or distract from the movie. But you also don't want a completely dark room, because the high contrast of the light from the screen may strain your eyes.
Ideally, a home theater should have soft ambient lighting connected to a dimmer. For the full theater experience, you can get an automatic dimmer and hook it up to the audio/video receiver. When you start up the movie, the lights will go down to a preset level on their own. Or you can control the lights with a remote control. Home theater systems can also be configured with curtains or cabinet doors operated by remote control. (Check out this site for more information on home-theater remote controls.)
As we've seen, the best home theater setup completely depends on your budget and your needs. If you just want a better entertainment system in the family room, a basic "home-theater-in-a-box" set, a DVD player and a good-sized television will be more than satisfactory. But if you want your own movie theater, with a huge screen and fantastic acoustics, you'll probably need to bring in a home theater expert and a contractor. The most important thing is to try everything out ahead of time to make sure your movies will look and sound great.
For lots more information on home theaters, including reviews of specific components, check out the links on the next page.
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