|
Home Theater is like a puzzle. It takes many different pieces that fit together
to create a total presentation. Each piece fits in a different spot, and together
they make a beautiful picture -- and sound in this case.
Understanding each component's role is helpful when making choices on which ones
to buy. And knowing more about component features makes it easier to set up and
use them to their best ability.
Front
Screen vs. Rear Screen Projection
Any television over 41" is a usually a projection television consisting of a separate
projector and screen. Projection televisions have either a front or rear screen
and each has its advantages. FRONT
SCREEN 
Front Screen doesn't require as much construction. When working with a
finished space, front screen projection is usually the better option because it
eliminates the need for tearing out any walls.
Because the projector hangs from the ceiling above the audience, it doesn't take
up floor space like a rear screen. The
downside is that front screens require a totally dark space or the image will
appear washed out. If controlling the light in the viewing room is difficult,
a front screen probably isn't the best choice. REAR
SCREEN 
A Rear Screen on the other hand will tolerate some ambient light. But a
rear screen mounted in a wall requires enough space behind it for the projector
and the projector's throw distance. It is possible to reduce the space somewhat
by bouncing the image off mirrors.
One big advantage to rear screen is that the equipment is hidden from the viewers.
The noise of the cooling fans for the projector is also lessened when behind cabinetry
or walls.
Components Explained
TELEVISION
A home theater needs to have a large screen television. The maximum size
of a tube-type television is 45" and only a few companies make them that big.
Generally, anything larger than 41" is a projection television. SCREEN
Screens are manufactured with different materials. Some are little more
than a matte-finished screen (for front screen) while others are made of
acetate sheets with complex technologies for improving brightness and clarity.
For
our home theater we used a rear projection screen of acetate with a fresnel pattern
molded into the projector side of it for capturing the image and funneling it
towards the viewer, and a lenticular pattern on the viewer side that greatly increased
the angle of view. PROJECTOR
With a projection television, the projector plays the most important role
in image quality. Whether dealing with front or rear screen, the biggest factor
in choosing a projector is finding one capable of projecting a very bright, clear
image.
There are three different grades available in projectors: video, computer,
and graphics. Video has the lowest number of lines of resolution (around
400). Graphics grade can handle about 1280 lines, perfect for high definition
television or movies that have been line doubled or quadrupled. RECEIVER
In most home theater systems, the receiver is the brain of the system.
It is where all the audio comes together and then. Most home theater receivers
have inputs and outputs, a built in tuner, surround sound capabilities, built
in amplifiers, and some even have a built in equalizer. CONTROLLER
High-end
systems will most likely have a controller instead of a receiver. In this
case, the controller is the most important piece in the system. It processes the
audio tracks coming from the source, divides it into the various channels, and
sends them to the separate amplifiers.
The controller also handles both audio and video signals and acts as a switching
device between the different sources. AMPLIFIER
Amplifiers are the power behind the system. Amps should be able to handle
the huge range of frequencies found in movie soundtracks and they should be able
to do it without distortion or clipping.
TUNER
A home theater system utilizing a controller instead of a receiver will need a
separate tuner for radio stations. Most tuners today are digital with multiple
preset buttons and scanning features. CD
PLAYER A
CD player is synonymous with quality audio and is necessary for any home
theater system to listen to your favorite music. Some CD players are separated
into two components: the drive unit for the mechanical portion of spinning
the disc and reading the information on it, and the Digital Audio Processor
(DAP) for all of the electronic processing.
All CD players have these features but they're usually housed in one piece of
equipment. Separating the two allows you to use the DAP to send and receive' signals
from other components through input/output jacks.
The advantage to separate units is that the processor is generally higher
quality than those found in most components and will be able to supply better
audio from other components. You can often improve the audio coming from a laser
disc player, by running its digital signals through a DAP. EQUALIZER
Once a room's acoustics have been physically optimized as much as possible, the
addition of an equalizer will fine tune the room's acoustics and balance
the frequencies.
LASERDISC
PLAYER Currently,
the laserdisc is the best way to watch a movie at home. The image you get from
a laserdisc player is sharper than that from a VCR and the audio is CD
quality.
Moving through the program material is easier too. Movies are divided into chapters
which are listed on the jacket like a CD. If you want to move to a specific part
of the disc, just enter the chapter number and you're there.
Movies released on videotape are generally resized to fit the screen size of a
standard television. But, movies on laserdisc are usually available in letterbox
or widescreen format as well as the resized version.
Depending on how the laserdisc was recorded, it is possible to have a completely
still freeze frame, and multiple speeds of slow motion and fast forward. Many
new laserdiscs are encoded with Dolby AC-3 sound and most laserdisc players also
function as a CD player.
DVD
PLAYER Digital
Versatile Discs (DVDs) are one of the hottest new elements of a home
theater system. DVDs are a cross-media platform for music and computers whose
technology most likely someday will replace the VCR.
A DVD player makes a great addition to the home theater system for many
reasons including its audio support of Dolby Digital/AC-3 and Dolby Pro Logic.
And the DVDs compact size makes it more easily stored than laserdiscs.
DVDs offer multiple options for specific viewing tastes. Each disc contains multiple
aspect ratios including standard television, widescreen, and letterbox for
your choice of viewing. The small discs are capable of storing eight different
languages for soundtracks and an additional 32 subtitle languages. DVD material
also comes with multiple rating options and some DVD players come with parental
control capability to only play certain ratings off the discs.
Pre-recorded movies are currently being released on DVD with an average price
tag between $18 and $30, comparable to today's videotape releases.
VCR
Still the most common playback source is the VCR. Its biggest advantage is recordability.
Disadvantages of the VCR include tape wear and damage, non-instant access, and
on a large-screen TV, the resolution just doesn't compare with the resolution
achieved with laser disc players. DSS
RECEIVER 
This is not like the satellite dish of yesterday. Besides being a lot smaller
(about the size of a large pizza) Digital Satellite Systems (DSS) are more
technically advanced. They receive digital satellite signals that carry superior
image capabilities similar to a laserdisc player with CD quality sound.
They're
easy to setup and tune in and will be able to accept future television standards
like high definition television and six-channel surround sound. Monthly service
plans cost about the same as standard cable service. LINE
DOUBLER 
The quality of a projected video image on a large screen can be improved in quality
by using a line doubler. A video image is made up of approximately 500
horizonal scan lines, but because of the way it scans, only half the lines are
shown at one time. A line doubler presents all the scan lines at the same time,
thereby increasing its sharpness. At the same time it cleans up imperfections
in the video signal.
A
line quadrupler does the same and adds information between the scan lines
for even higher resolution. INTERPOLATOR
An
alternative to a line doubler or quadrupler is an interpolator. It also
increases the quality of a projected video image on a large screen but in a different
way. An interpolator determines the optimal scan rate for the monitor used. It
then creates and fills in the picture information to precisely fit that monitor
for the best quality image.
An interpolator also changes aspect ratios on the monitor to match the format
of the source signal. An example would be a letterbox image can be made to fill
a screen eliminating the top and bottom banding.
An interpolator mixes video and computer images which electronically are very
different, and until now could not be mixed. This capability may become more essential
in the future as video and computer applications converge.
SPEAKERS
Since
sound attributes to half of the home theater experience, it's a good idea to get
the best speakers you can afford. Like amplifiers, speakers should be able
to reproduce a large frequency range clearly without distortion.
No two speakers sound alike so selecting them is often a matter of personal listening
preference. A home theater should have an array of six speakers or more to properly
create sound. These will include left, right, and center speakers across the front;
a couple of surrounds and a subwoofer or bass unit to create the low, loud, feel-it-in-your-stomach
sounds.
RACK
SYSTEM 
You can see by the list of equipment that a home theater system can take up a
lot of room. A rack system organizes the components and helps to keep pieces
orderly and neat looking.
Some rack systems come with rollers which slide completely out of the cabinetry
making it easier to get at the cables on the back to make changes. Modular rack
systems also make it easy to add components in the future. CABLES
& INTERCONNECTS 
They may seem relatively unimportant compared to the rest of the equipment, but
cables and interconnects can make a difference between a good sounding
system and a great sounding system. This is true on any size system from the low
end to the highest quality. The signals between components and speakers need to
flow unrestricted or the output will suffer.
Cables should be a heavy gauge and the connectors should be gold plated. Some
experts even say to allow as much as 10% of your home theater budget for cable.
REMOTE
CONTROL Most
electronic equipment has a remote control. Imagine a whole rack full of
components each with individual remotes -- you know that the coffee table probably
won't be big enough to handle them all! But you still need to be able to control
all those devices.
If you happen to purchase all your equipment from the same manufacturer, you might
be able to control everything from the receiver remote. But most people don't
buy everything from one manufacturer and that's where a universal remote comes
in.  There
are a number of sophisticated systems out there that will not only do the job
but make things a little simpler.
A high-end touchpad system we installed includes a tabletop device with
a large screen programmed to control each component. There's a screen for each
component with icons that represent different functions. Simply press the symbol
on the screen and it performs that function.
The remote transmits information by radio waves rather than the traditional infrared
waves so you can keep the components behind closed doors and still be able
to operate them. Inside the rack is the remote receiver that takes the information
from the radio waves, processes it and sends a command via infrared through wires
to the component. Connecting
Components Sketching
out a simple connection plan can be helpful for installing a home theater system.
This can help to figure out the general layout of the elements, considering cable
connector lengths, the best location for remote usage, easy setup and maintenance.  Exactly
how home theater components are physically connected varies according to what
equipment is being used. The owner's manuals will be a great help in this department.
If you have a lot of equipment, you might consider hiring a professional to install
the system.
You can see a basic plan of how our components were connected in the high-end
home theater we installed on our recent home theater project. | 
