I'm doing some research on how surround technology works. I'm not just
talking about speaker placement, but the package as a whole. I want to
know how a disc is encoded, how the player deocodes the information
and sends it to the receiver. Then how the receiver transmits only
certain frequnecies to certain speakers. And finally how we interpret
these sounds in our ears.

Thanks

To sum up:
How Surround Sound works
How (DVD) discs are encoded
How the receiver decodes and transmits certain frequencies to each speaker
How the ear perceives transmitted sound

What I have found:
http://www.dolby.com/tech/Multichannel_Music_Mixing.pdf

Terms you can use:
Psycho-acoustics
Acoustic design encoding
Audio Theory
Sound Interpretation
Occupational hearing conservation

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Request for Question Clarification by andrewxmp-ga on 30 May 2004 09:49 PDT

Hi,

Will the comment from 1anton1 suffice?  I could certainly find many
more resources on this as an answer, at whatever technical level would
be most useful.  I have plenty of resources for aspects that he did
not touch on, such as how sound is encoded, as well as how the human
ear percieves these sounds and interprets them as particular sound
sources.  Please let me know if you would like one of us researchers
to go ahead with this, as well as any further specifics about your
question.  Thanks.

-Andrewxmp

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Clarification of Question by digital_goonie-ga on 31 May 2004 05:57 PDT

Andrewxmp,
Anton's comment was suffice to a point, but there is information
needed.  Please feel free to research a more detailed solution to the
question.  As far as complexity is concerned, you can get pretty
detailed.  Engineer level detailed.

One thing that shouldn't be forgotten about is how the receiver
decodes and transmits certain frequencies to each speaker.  You hit
the nail on the head by saying what information you have, because it's
exactly what I was looking for.

Digital_Goonie

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Request for Question Clarification by techtor-ga on 07 Jun 2004 08:41 PDT

Hello Digital_goonie,
I noticed that your question hadn't been touched a while, and you've
consequently raised the price, but it touched off my interest a bit.
I've seen a PDF pamphlet by a DVD manufacturer on the actual CD/DVD
making process, though it does not cover much of sound encoding and
decoding. I also found a basic explanation of surround sound workings
on Howstuffworks.com, but it may not have the engineer-level treatment
you require. So far the engineer-level explanation has not been found,
since such detailed documents seem to be not that easy to find on the
Net, but I or probably another researcher, including Andrewxmp, am
researching further on the topic.

You haven't mentioned if you are looking for information about dolby
surround (prologic) or dolby 5.1

Surround:
This is encoded in a stereo signal.  It is a very simple (but elegant) idea.
Any sound common to the left and right channel is removed, and then
sent to the centre channel.  Any sound exactly 90 degrees out of phase
between the left and right channels is removed and sent to both rear
speakers.  The remaining sound is played from either the left or right
speakers (front).

That is why some stereo CD's (not recorded with surround in mind) do
actually have a surround effect (this is not the best way to listen to
the CD).

Dolby 5.1:

This is a different beast altogether.  Each of the 5 main channels are
recorded seperately.  That essentially means that you could have 5
completely different songs playing (one from each speaker).  the .1
bit is for the subwoofer, this does not need anywhere near as much
information (frequency is severeley limited) as the other channels. 
This is recorded seperately too.

The information is all sent from the DVD player to the amp via an
opticle cable.  I have no idea how that works, but the amp decodes it
at the other end.  Not all systems use this method.  Some use a G9
type cable - 6 channels out from the DVD player to the amp.  Requires
6 phono leads.

I know I haven't fully answered your question, but hopefully have
given you a little more info than you had.  I have been using surround
and 5.1 for a few years now.

General:

Originally ppl reckoned that stereo playback from the rear channels
would go unnoticed.  This proved not to be the case.  There is a
massive difference.  Sometimes when I'm watching a movie on my system
I have great difficulty determining whether a sound (a bang or the
like) was from the movie, or someone knocking on my door.  I never got
that from a typical prologic setup.  The difference between the 2 is
massive.

HTH

Thank you for your help, I didn't know there was that much of a
difference between the two.  Surround (prologic) is what I am looking
for.