
Surround Sound Setup
The PC is becoming much more than just a home
computer. Its becoming the basis for the entire home entertainment system.
The PC has the capability for you to do work play games, connect to the
world, listen to music and watch DVD's. The idea that the PC could be the
center of entertainment in your would would suggest that its worth
spending a bit on your sound system. The first step her is obviously to
purchase a quality sound card. The second part of your sound system it
what we will be focusing on in this article. With the introduction of
DVD's to the PC system came the need for a proper surround sound. Dolby
digital 5.1 was taken on board and many sound cards had the facility to
distribute sound over 5.1 channel. Anyone with a 5.1 speaker setup could
get cinema quality sound around the room with the correct setup. Since
then the experience of sound has moved on even more to 6.1 and 7.1
channels.
Sound Channels
In a surround sound setup you will find that different speakers will
produce different sounds. There are four types of channel for the surround
setup. The center, front, the surround and the LFE (Low Frequency
Effects). The center speaker is used for the dialogue of the film etc. you
will soon know if your center speaker isn't working properly as you will
only hear noises and no words. do note though that when a stereo audio
source is used the center speaker will not produce anything at all. The
center speaker only works with a true 5.1 source.
The Front speakers produce the action noises and create the effect
of what sounds are coming from the right and the left. Anything that isn't
dialogue will come out of the front speakers. It is usual to have the
front speakers louder than the surround speakers.
The surround
speakers are used to give the true cinematic experience by adding depth to
the sound. with 5.1 surround sound you can hear things going past you and
you can tell the direction of the movement. The surround speakers are
generally quieter than the main front ones and are normally a little
further away from you.
The final part of your surround system is the subwoofer. You will notice that
with most mid range hi-fi's the speakers have two parts to them known as the
tweeter and the woofer. The tweeter produces the higher pitch noises and the
woofer the lower pitch. Satellite speakers for the PC usually come with only one
speaker cone. To create the best overall sound you also have a sub-woofer. This
piece of equipment can only produce LFE (Low Frequency effects). These LFE's
don't seem to have a direction when you are listening to them so only one is
required for a full effect. The subwoofer is very important to give the sound
some feel. Try turning the subwoofer off or down to minimum and see the
difference in your sound.
5.1 Channel Setup
This was the first true surround sound setup. There was a four point
surround system but the lack of centre channel prevented the true
cinematic sound experience. The 5.1 setup had 5 satellite speakers and a
subwoofer (the subwoofer is the .1 as it doesn't provide anything more
than the bass). The 5 satellite speakers were setup up as follows.
Centre speaker
Front left
Front right
Surround left
Surround right
To set up a 5.1 speaker system you should position them as above. The
centre speaker should be position either on top or underneath the screen
if your screen is on a stand. The front left and right should be set up on
either side of the screen or mounted on the wall behind the screen on
either side. The surround speakers should be setup approximately level
with your seating position. Do not neglect the position of the surround
speakers. Effectively these speakers set the 5.1 system aside from
standard stereo formats. The surround speakers produce the ambient effects
and special effects that cause the sound to fill the room. For example the
5.1 system allows you to hear a bullet whistle past you and cars roar
along side you. The setup is crucial if you are to achieve this.
Surround Sound Formats
Surround sound comes in many formats, each with its own system of
producing realist surround sound effects. Some specifically for the
home and others started life in the Cinema. You will find many
pieces of audio equipment will state all the types of surround sound
they are capable of decoding. Here are the most popular ones.
Dolby Surround - One of the
first systems to enter the home sound system market. Dolby surround
allows broadcasters to merge 4 channels (left, right, center and
mono) and encode them into 2 channels of audio. Two channels can be
used by a stereo system but a system with Dolby Pro Logic could
decode the signal and produce the 4 channel audio once again. Dolby
Surround is an analog system.
Dolby Digital - The first
digital surround channel audio format and the first to offer the 5.1
format (left, right, center, left surround, right surround and the
LFE or Low Frequency Effects channel). This is the primary format
for surround sound stored on DVD's
Dolby Digital EX - Designed
for the cinema, Dolby Digital EX carries an extra center channel
produced by one or two speakers, while it was designed for cinema
use it found its way to the DVD for films that were made with this
format.
Dolby TrueHD - As media types moved on to Blu-Ray and HD-DVD more information was
able to be stored on each disc. To this end Dolby TrueHD was
developed offering 100% lossless technology, 18Mbps bit rate and
24-bit/96Khz audio quality. Dolby TrueHD also has support for up to
8 sound channels. TrueHD is also supported by the High Definition
Media Interface (HDMI).
DTS - DTS stands for
Digital Theatre Sound. DTS was developed by a company of the same
name and is a rival technology to Dolby. It offers the same multi
channel sound experience but is incompatible with Dolby sound
tracks. You will find most decent Audio hardware can decode both DTS
and Dolby sound tracks.
DTS-ES - Digital Theatre
Sound - Extended Surround. DTS-ES is a 6.1 channel format. This
system adds an extra channel for a rear surround channel. Audio
encoded with 6.1 sound could allow for the experience of objects
appearing to come from behind you.
TruSurround XT - Not a real
surround sound format but a extension of the SRS TruSurround format.
TruSurround XT is capable of taking multi channel audio 5.1 / 6.1
formats and can translate them in to a 2 channel format with virtual
surround effects. Useful for systems with simple stereo speakers or
headphones.
Compare 5.1 Surround Sound Speakers
Next - 6.1 and 7.1
speaker setups