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Columbia ISA Audio Video |
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Home Theater
Home theater is one of the hottest things on the market right now - but what is it? Why would you want it? And what do you really need to buy to enjoy it? Why Home Theater? Anyone who has enjoyed the visuals of the wide-screen movie, and sonics of movie theater sound knows from experience how much more this experience enhances your enjoyment of a movie than watching the same movie at home on your standard CRT TV set with, at best, stereo sound. What if you could have the movie theater experience, but at your home, on your time schedule and under your complete control. What if you could sit in "your" seats and know exactly who your seatmates are and set the air-conditioning to your settings? What if you controlled the volume of sound to your liking and never missed a portion of the movie, because you control the "projector". Well now you can get fairly close to this. With today's wide-screen high-def televisions and multi-channel sound systems, the theater experience "at home" could rival the old movie theaters. The goal is to duplicate, in your own home, the surround sound envelopment and integration of picture, drama, and sound that you experience in a commercial Dolby Surround movie theater, only on a smaller scale. The entertainment is for you, and your friends and family. That may sound ambitious, but surprisingly, even a basic home theater system can deliver remarkably enhanced playback of DVD/Blu-ray movies, rental videotapes, and even TV shows that are recorded and broadcast in Dolby Surround. A basic home theater system consists of a pair of front left and right speakers on either side of the TV, a center-channel speaker on top (or beneath) the TV set to anchor the actors dialog at the TV screen no matter where you sit, a pair of smaller surround speakers to either side of your seat that carry all the effects and ambient sound of a movie or TV show-street noises, planes flying, jungle sounds, the noise of rain, thunder, or crickets, distant explosions or rumbles, and all the myriad of other sounds that make up a movie soundtrack, including, of course, the movie score, the music and songs that underscore the action on screen. Lastly, most home theater systems add a subwoofer, typically a square black box that produces ultra-deep bass sounds-rumbles, storms, deep musical bass and the like. That's a total of six speakers, including the subwoofer, and it comprises "5.1-channel" sound (the .1 is the subwoofer bass channel). But all the speakers needn't be big. Because the subwoofer carries much of the low bass energy, the other "satellite" speakers can be compact and visually unobtrusive, no larger than a hardcover book. To this mix, you must add a Dolby Digital Surround Sound Audio/Video receiver, which contains all the circuitry to "decode" the Blu-ray, DVD, streaming or videotape movie soundtrack and effects, plus five built-in amplifiers for each of the five loudspeaker channels (the subwoofer always has its own dedicated built-in amplifier). And finally, you need a Blu-ray/DVD player. (You can use a Hi-Fi stereo VCR, but it will only deliver analog Dolby Surround, not 5.1-channel Dolby Digital.) Bringing Theater
Home A Basic System Might
Include: More-elaborate Systems Might
Include: Why All the
Speakers? Question: Answer: Recently Dolby and THX developed a new 6.1 channel audio system made
famous with Star Wars The Phantom Menace. The new format added a sixth
channel in the center of the rear. DTS released a similar 6.1 channel
format known as DTS-ES. The new 6.1 formats provide front left, center,
and right channels as well as rear left, center, and right channels along
with the subwoofer bass effects .1 channel. DTS has provided two 6.1 formats, one fully discrete and one
matrixed.
With the discrete format each of the six main channels as well as the
subwoofer channel occupies its own space on the recorded disc. By
contrast, the matrixed format encodes one additional channel into the two
rear channels of a 5.1 sound track. This additional channel is later
decoded by a special decoding chip. It is not discrete because it does not
exist on its own, it is an extra channel coded into two others using a
mathematical algorithm (this is how analog Dolby Pro-Logic provides a
center channel and rear channel from a two channel recording). Discrete
channels are better because there is no channel interaction. Whenever one
channel is derived from others there is the possibility for errors and
decoding artifacts that muddy the sound quality. So how big of an impact is the discrete versus matrixed issue for a
rear center surround channel? In reality, it does not have that big an
impact since this is an effects channel. It is unlikely you will notice
much of a difference if any at all in normal listening. In fact, the
Dolby/THX 6.1 surround format, THX Surround EX, offers only a matrixed
option. Question: Answer: If your TV does not have audio outputs, you can use essentially the same procedure with your VCR. Connect the audio outputs from the VCR or DVD recorder to your receiver then when you watch TV use your VCR as the source using its tuner to change channels, etc. (your TV will simply act as a monitor). Audio/Video receivers do not have TV tuners in them like VCRs, TVs and DVD recorders do. Therefore they also do not have a coax cable TV input connection. If you can connect the video output (for example, composite or S-Video) of a cable box, VCR or DVD recorder to a video input on the A/V receiver, then you can use the receiver as a switch to select your sources. Question: Answer: Another problem you may encounter is your TV itself.
You need a
television capable of stereo to output a stereo signal (if your TV is not
stereo capable there should be only one RCA audio output - if there is
one). If your TV does not have stereo audio outputs, right and left
(usually red and white), then you will not be able to get stereo sound. To
produce sound from stereo speakers (left and right) you could use a
Y-splitter to split the single RCA cable from your TV into two cables to
feed the same mono signal to both channels of your stereo system. Your other potential problems lie in bad equipment.
It is possible that
one of your RCA cables is bad. Try switching cables and see if the problem
switches channels, if so you probably have a bad cable. You could also
have a problem with the outputs on your TV or the inputs on your stereo
system. Try switching the cables connections to a different set of inputs
on your stereo system to see if the problem persists. Also, be sure your
stereo system and speakers work properly with other components as well (CD player, DVD
player, etc.). If there is a problem using one of these other sources then
your issue may be with a faulty speaker connection.
Question: Answer: Next, connect up your speakers. Be sure that all the speaker wire is
tightly connected and properly routed (left to left, right to right,
etc.).
Turn on your TV and go into the TV menu. Find the section on audio and
turn off the TV''s internal speakers. You will be using your surround
sound system for audio playback instead of the TV speakers. All volume
control will go through your receiver and its remote control whether you
are watching TV or a VHS tape or listening to the radio.
Once your system is properly set up, you should not run into the
problems you mentioned. For future reference, however, it is entirely
possible at times for all sound to come only from the center speaker. You
can force all sound to come through the center by putting your receiver
into mono mode. Assuming it is not set to mono, a mono video tape or TV
show will probably play only through the center channel unless you set the
receiver to stereo mode (Dolby Pro-Logic routes mono sounds to the center
channel).
As far as your problem with volume control after having turned on the
tuner (the tuner is used for listening to the radio), this was probably
simply a problem of using the wrong remote or having an improper set-up.
Remember that you will use your receiver remote control ONLY for volume control, not the TV or VCR remote. You will
control the volume for the TV, VCR, radio, etc. through your receiver,
which powers your speakers and also provides surround sound
functionality. Question: Answer: What do you do, however, if you do not have a receiver or your receiver
does not have video switching capabilities? First, you should consider
purchasing a good surround sound receiver if you do not have one. A
receiver will provide a lot of
flexibility with much better sound quality than your TV can provide (the
difference between TV sound and that provided by a good receiver and good
speakers is night and day). Especially since you have invested in a DVD
player and satellite system and receiver would be an excellent purchase.
Just be sure it has Dolby Digital processing and enough video inputs to
satisfy your needs. You should also look for a receiver with enough
S-video inputs for all your sources for future upgrades if you
purchase a new TV with s-video inputs. With any option you pursue you actually only need three a/v inputs
since your antenna will connect directly to your TV (one each for your DVD
player, VCR, and satellite system). However, a fourth input group is a
good idea for future purchases such as a video game system or a hard drive
video recorder (personal video recorder). If you have a receiver you can
run a pair of stereo RCA audio cables from the audio outputs on your TV to
a pair of audio inputs on your receiver to enjoy television viewing in
surround sound through your home theater system. Question: Answer: If your inputs are correct and you have selected the proper input on
your receiver then the next most likely cause for your problem is an
improper input setting. Your CD output is in PCM format, while your DVD
audio output is most likely in Dolby Digital AC-3 (5.1). You may need to select
Dolby Digital AC-3 (5.1) for your DVD player input when playing a DVD
(although in most cases your receiver/pre-amp should detect the signal and
do this for you). Also, be sure that your DVD is not a DTS DVD, unless your
receiver/pre-amp is capable of decoding DTS signals (most DVDs are
recorded using Dolby Digital AC-3).
When you play a DVD be sure that the DVD is actually playing. If it is
stuck on a menu you may not get any sound. Of course also check that it is
not muted.
If you still are unable to get any sound from your DVDs try using the
analog RCA audio outputs on your DVD player. You should be able to get
sound using the left and right RCA audio outputs from both your CDs and
DVDs played in your DVD player. You will want to use the digital output so
you can enjoy 5.1 surround sound, but you can test that your player and
DVDs are operating properly this way. SWS
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