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Surround Sound Decoding Question

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Anonymous
June 29, 2004 2:58:19 AM

Archived from groups: rec.audio.high-end (More info?)

Hello.

I recently upgraded from two-channel to 5.1-channel, and I have a
respectable audio system (Adcom separates, Denon DVD-2900 universal
disk player, B&W 700-series speaker system). I like to think I know
what I'm doing, but I'm new to surround sound, so . . .

I have some DVDs that include a "Dolby Surround" mix, that is, the
older matrixed implementation that requires decoding by Dolby Pro
Logic. But my preamp, like all newer preamps and receivers, includes
DPLII, which can derive a pretty-good 5.1 presentation out of just
about *anything*.

So my question is: What does it matter if a disk is encoded in "Dolby
Surround"? I mean, with DPLII, does a Dolby Surround-encoded disk
yield better results than an unencoded stereo mix?

By the way -- just so there's no confusion -- I'm not referring to
discrete Dolby Digital or DTS soundtracks, only to good ol' Dolby
Surround.

Thanx.
Anonymous
June 30, 2004 2:38:58 AM

Archived from groups: rec.audio.high-end (More info?)

Colonel Tomb <colonel_tomb@yahoo.com> wrote:
> Hello.

> I recently upgraded from two-channel to 5.1-channel, and I have a
> respectable audio system (Adcom separates, Denon DVD-2900 universal
> disk player, B&W 700-series speaker system). I like to think I know
> what I'm doing, but I'm new to surround sound, so . . .

> I have some DVDs that include a "Dolby Surround" mix, that is, the
> older matrixed implementation that requires decoding by Dolby Pro
> Logic. But my preamp, like all newer preamps and receivers, includes
> DPLII, which can derive a pretty-good 5.1 presentation out of just
> about *anything*.

> So my question is: What does it matter if a disk is encoded in "Dolby
> Surround"? I mean, with DPLII, does a Dolby Surround-encoded disk
> yield better results than an unencoded stereo mix?

> By the way -- just so there's no confusion -- I'm not referring to
> discrete Dolby Digital or DTS soundtracks, only to good ol' Dolby
> Surround.

> Thanx.


A Dolby Surround track (Dolby Pro Logic) was *mixed* with 4-channel
DPL decoding in mind (front left/center, right, and mono rear).
In other words, sound placement was dictated by the Dolby mixing
engineer who mixed the track.

For a normal stereo track played through DPL II, on the other
hand, sound placement is dictated by the interaction of
the DPL II algorithm and the phase/volume information on the track.

A DPL I track played through DPL II will have its rear channel
reconfigured into stereo. Some receivers also allow you to
run DPL II in 'emulation' mode, which essentially allows
DPL-I encoded tracks to be played back as originally encoded
(four channel) -- if you needed to do that for some reason.

As far as ;better; results, all one can say is that each
way will sound *different*.



--

-S.
Why don't you just admit that you hate music and leave people alone. --
spiffy <thatsright@excite.co>
Anonymous
June 30, 2004 2:43:08 AM

Archived from groups: rec.audio.high-end (More info?)

"Colonel Tomb" <colonel_tomb@yahoo.com> skrev i melding
news:cbq7qb01lfp@news3.newsguy.com...
> Hello.
>
> I recently upgraded from two-channel to 5.1-channel, and I have a
> respectable audio system (Adcom separates, Denon DVD-2900 universal
> disk player, B&W 700-series speaker system). I like to think I know
> what I'm doing, but I'm new to surround sound, so . . .
>
> I have some DVDs that include a "Dolby Surround" mix, that is, the
> older matrixed implementation that requires decoding by Dolby Pro
> Logic. But my preamp, like all newer preamps and receivers, includes
> DPLII, which can derive a pretty-good 5.1 presentation out of just
> about *anything*.
>
> So my question is: What does it matter if a disk is encoded in "Dolby
> Surround"? I mean, with DPLII, does a Dolby Surround-encoded disk
> yield better results than an unencoded stereo mix?

Some products have a "pro logic emulation" feature.


Esp1
Related resources
Anonymous
July 2, 2004 6:41:03 AM

Archived from groups: rec.audio.high-end (More info?)

Uptown Audio <uptownaudio@rev.net> wrote:
> There is no need to justify your decision, Ban. I share your thoughts
> if that is of any comfort (or distress!). Stereo is a perfectly good
> format and has served the entire world, that can afford it, well for
> many years.

Two-channels stereo was a compromise from the git-go, as a perusal
of the history of home audio will show.

> There is no need to run to a new format just because it
> promises something new. New formats should deliver something better,
> which we have both heard that it clearly does not. I am not knocking
> true discrete surround if it is done properly and it is fun for
> movies, but totally unnecessary. A matrixed or quasi-surround of any
> form has always proven to be either annoying, distracting, destructive
> or a combination of the lot.

Nonsense. You can't 'prove' something like that; any number of
positive reviews 'disproves' that thesis. Tom N. and I have
given two; here's another:

http://128.121.62.219/volume_8_1/dolby-prologic2-3-2001...

Moreover, there's no reason to 'privelage' 'true discrete surround'
on this basis. "True discrete surround' has just as much
potential to be annoying, distracting , destructive as
algorithm-based surround.

> To make matters worse, you can pay extra
> for it!

You can, but it appreas to be standard on receivers for the
last couplke of years.

> That "technology" is not new, but has been around for many
> years and marketed in a number of ways, Dolby being the most
> successful seller.

There's no reason to put quotes around word 'technology'.

> As most people here realize, you can get higher
> quality components by limiting the number of channels to two and
> remaining within the same budget.

At least some people here realize that the point of diminishing, if not
zero, return is reached for some classes of components rather earlier than
'high end' mythology dictates.

> That almost always results in better
> sound quality and certainly will result in both if you are a good
> listener while you shop.

Given that there's no way to get 'surround' from a two-channel setup,
some might disagree with that claim.

--

-S.
Why don't you just admit that you hate music and leave people alone. --
spiffy <thatsright@excite.co>
Anonymous
July 3, 2004 8:51:11 AM

Archived from groups: rec.audio.high-end (More info?)

"Uptown Audio" <uptownaudio@rev.net> wrote in message
news:IN1Fc.10164$7t3.7956@attbi_s51...
> There is no need to justify your decision, Ban. I share your thoughts
> if that is of any comfort (or distress!). Stereo is a perfectly good
> format and has served the entire world, that can afford it, well for
> many years. There is no need to run to a new format just because it
> promises something new. New formats should deliver something better,
> which we have both heard that it clearly does not. I am not knocking
> true discrete surround if it is done properly and it is fun for
> movies, but totally unnecessary. A matrixed or quasi-surround of any
> form has always proven to be either annoying, distracting, destructive
> or a combination of the lot. To make matters worse, you can pay extra
> for it! That "technology" is not new, but has been around for many
> years and marketed in a number of ways, Dolby being the most
> successful seller. As most people here realize, you can get higher
> quality components by limiting the number of channels to two and
> remaining within the same budget. That almost always results in better
> sound quality and certainly will result in both if you are a good
> listener while you shop.

I agree with all that you write. I find that a proper 2 channel set-up in a
good listening room yields its own ambiance effects by using the room's own
boundaries. Moreover I remain convinced that multi-channel only serves to
*dilute* the very L-R soundstage which I'm concerned with hearing. It would
be fun for me to *occasionally* hear a classical orchestra through the ears
of a center-stage seated performer, but MCH has not performed that trick for
me. (I can and do get a kick out of the likes of watching while listening to
a helicopter move across the room housing my ((meager)) multi-channel
set-up.)
Anonymous
July 3, 2004 11:35:09 AM

Archived from groups: rec.audio.high-end (More info?)

"Steven Sullivan" <ssully@panix.com> wrote in message
news:2X3Fc.10980$7t3.1475@attbi_s51...
> Uptown Audio <uptownaudio@rev.net> wrote:
> > There is no need to justify your decision, Ban. I share your thoughts
> > if that is of any comfort (or distress!). Stereo is a perfectly good
> > format and has served the entire world, that can afford it, well for
> > many years.
>
> Two-channels stereo was a compromise from the git-go, as a perusal
> of the history of home audio will show.
>
People who derive pleasure from headphone systems couldn't possibly agree
less. What could come closer to true 2 channel listening?

A matrixed or quasi-surround of any
> > form has always proven to be either annoying, distracting, destructive
> > or a combination of the lot.

To my ears it only proves to dilute the very soundstage I want to focus upon
hearing. If a recording was made using only 2 or 3 microphones, why should
it be heard with anything more than two or three speakers?

> Nonsense. You can't 'prove' something like that; any number of
> positive reviews 'disproves' that thesis. Tom N. and I have
> given two; here's another:
>
> http://128.121.62.219/volume_8_1/dolby-prologic2-3-2001...
>
More "Nonsense".Quoting anything written by another party doesn't prove your
point, but only serves to show that someone else agrees with you. If I look
hard enough, I'm certain to find someone who finds that the sky is falling.
Anonymous
July 3, 2004 9:05:15 PM

Archived from groups: rec.audio.high-end (More info?)

On Sat, 03 Jul 2004 07:35:09 GMT, "Norman Schwartz" <nmsz1@att.net>
wrote:

>"Steven Sullivan" <ssully@panix.com> wrote in message
>news:2X3Fc.10980$7t3.1475@attbi_s51...

>> Two-channels stereo was a compromise from the git-go, as a perusal
>> of the history of home audio will show.
>>
>People who derive pleasure from headphone systems couldn't possibly agree
>less. What could come closer to true 2 channel listening?

Binaural recordings on headphones are not apt comparisons to stereo
recordings on headphones. 2channel stereo is a compromise with phones
and with speakers. Binarural recordings on headphones is not.

Kal
Anonymous
July 4, 2004 6:54:25 PM

Archived from groups: rec.audio.high-end (More info?)

Norman Schwartz <nmsz1@att.net> wrote:
> "Steven Sullivan" <ssully@panix.com> wrote in message
> news:2X3Fc.10980$7t3.1475@attbi_s51...
> > Uptown Audio <uptownaudio@rev.net> wrote:
> > > There is no need to justify your decision, Ban. I share your thoughts
> > > if that is of any comfort (or distress!). Stereo is a perfectly good
> > > format and has served the entire world, that can afford it, well for
> > > many years.
> >
> > Two-channels stereo was a compromise from the git-go, as a perusal
> > of the history of home audio will show.
> >
> People who derive pleasure from headphone systems couldn't possibly agree
> less. What could come closer to true 2 channel listening?

> A matrixed or quasi-surround of any
> > > form has always proven to be either annoying, distracting, destructive
> > > or a combination of the lot.

> To my ears it only proves to dilute the very soundstage I want to focus upon
> hearing. If a recording was made using only 2 or 3 microphones, why should
> it be heard with anything more than two or three speakers?

<shrug> To my ears, it actually solidifies the soundstage while expanding
it..

> > Nonsense. You can't 'prove' something like that; any number of
> > positive reviews 'disproves' that thesis. Tom N. and I have
> > given two; here's another:
> >
> > http://128.121.62.219/volume_8_1/dolby-prologic2-3-2001...
> >
> More "Nonsense".Quoting anything written by another party doesn't prove your
> point, but only serves to show that someone else agrees with you. If I look
> hard enough, I'm certain to find someone who finds that the sky is falling.

I agree completely --which is why I wrote 'nonsense'. Which would be
clear if you hadn't snipped the post I was replying to.

--

-S.
"We started to see evidence of the professional groupie in the early 80's.
Alarmingly, these girls bore a striking resemblance to Motley Crue." --
David Lee Roth
Anonymous
July 4, 2004 7:00:02 PM

Archived from groups: rec.audio.high-end (More info?)

"Kalman Rubinson" <kr4@nyu.edu> wrote in message
news:fHBFc.18064$%_6.15238@attbi_s01...
> On Sat, 03 Jul 2004 07:35:09 GMT, "Norman Schwartz" <nmsz1@att.net>
> wrote:
>
> >"Steven Sullivan" <ssully@panix.com> wrote in message
> >news:2X3Fc.10980$7t3.1475@attbi_s51...
>
> >> Two-channels stereo was a compromise from the git-go, as a perusal
> >> of the history of home audio will show.
> >>
> >People who derive pleasure from headphone systems couldn't possibly agree
> >less. What could come closer to true 2 channel listening?
>
> 2channel stereo is a compromise with phones
> and with speakers.

Two channel stereo recordings with speakers does present a problem not
encountered when these same recordings are heard via headphones. These are
the recordings most of us listen to. IMO this problem arises mainly because
some left channel *speaker* sound is perceived by the right ear and vice
versa, some right channel sound enters the left ear. (Ditto for the sound
reflected from room boundaries, including uncarpeted floors.) Mr. Bob Carver
(a name frowned upon in audiophile circles except perhaps for his Amazing
Loudspeakers, which in itself ought to prompt a hullabaloo) came forth with
a device named the "C-9" hologram generator, also incorporated into other of
his components) which cancels a fraction of this cross channel perceived
sound, using out of phase signals fed to opposing speakers having
appropriate time delays. If you carefully measure distances between the
sweet spot and the two speakers and then engage your pre-amps balance
control; full left and R, both channels take on new dimensions which for me
at least approximates headphone listening. Not, only does the C-9 serve to
set-up this aspect in loudspeaker listening, when employed to maximal
effect, you will have set your speakers in that optimal equilateral triangle
recommended for loudspeaker placement.
Anonymous
July 5, 2004 9:36:35 AM

Archived from groups: rec.audio.high-end (More info?)

On 4 Jul 2004 15:00:02 GMT, "Norman Schwartz" <nmsz1@att.net> wrote:

>"Kalman Rubinson" <kr4@nyu.edu> wrote in message
>news:fHBFc.18064$%_6.15238@attbi_s01...
>> 2channel stereo is a compromise with phones
>> and with speakers.
>
>Two channel stereo recordings with speakers does present a problem not
>encountered when these same recordings are heard via headphones. These are
>the recordings most of us listen to. IMO this problem arises mainly because
>some left channel *speaker* sound is perceived by the right ear and vice
>versa, some right channel sound enters the left ear. (Ditto for the sound
>reflected from room boundaries, including uncarpeted floors.) Mr. Bob Carver
>(a name frowned upon in audiophile circles except perhaps for his Amazing
>Loudspeakers, which in itself ought to prompt a hullabaloo) came forth with
>a device named the "C-9" hologram generator, also incorporated into other of
>his components) which cancels a fraction of this cross channel perceived
>sound, using out of phase signals fed to opposing speakers having
>appropriate time delays. If you carefully measure distances between the
>sweet spot and the two speakers and then engage your pre-amps balance
>control; full left and R, both channels take on new dimensions which for me
>at least approximates headphone listening. Not, only does the C-9 serve to
>set-up this aspect in loudspeaker listening, when employed to maximal
>effect, you will have set your speakers in that optimal equilateral triangle
>recommended for loudspeaker placement.

The cancellation helps in some ways but makes for poorer center fill
and smaller sweet spot. In addition to Carver, Polk attempted this
with his "MARS" configuration. For a better approach to improved
stereo from 2channel sources, see Meridian's Trifield and Bongiorno's
Trinaural processing which take their inspiration from Blumlien and
Klipsch.

Kal
Anonymous
July 5, 2004 7:36:28 PM

Archived from groups: rec.audio.high-end (More info?)

Kalman Rubinson kr4@nyu.edu wrote:

>
>On 4 Jul 2004 15:00:02 GMT, "Norman Schwartz" <nmsz1@att.net> wrote:
>
>>"Kalman Rubinson" <kr4@nyu.edu> wrote in message
>>news:fHBFc.18064$%_6.15238@attbi_s01...
>>> 2channel stereo is a compromise with phones
>>> and with speakers.
>>
>>Two channel stereo recordings with speakers does present a problem not
>>encountered when these same recordings are heard via headphones. These are
>>the recordings most of us listen to. IMO this problem arises mainly because
>>some left channel *speaker* sound is perceived by the right ear and vice
>>versa, some right channel sound enters the left ear. (Ditto for the sound
>>reflected from room boundaries, including uncarpeted floors.) Mr. Bob Carver
>>(a name frowned upon in audiophile circles except perhaps for his Amazing
>>Loudspeakers, which in itself ought to prompt a hullabaloo) came forth with
>>a device named the "C-9" hologram generator, also incorporated into other of
>>his components) which cancels a fraction of this cross channel perceived
>>sound, using out of phase signals fed to opposing speakers having
>>appropriate time delays. If you carefully measure distances between the
>>sweet spot and the two speakers and then engage your pre-amps balance
>>control; full left and R, both channels take on new dimensions which for me
>>at least approximates headphone listening. Not, only does the C-9 serve to
>>set-up this aspect in loudspeaker listening, when employed to maximal
>>effect, you will have set your speakers in that optimal equilateral triangle
>>recommended for loudspeaker placement.
>
>The cancellation helps in some ways but makes for poorer center fill
>and smaller sweet spot. In addition to Carver, Polk attempted this
>with his "MARS" configuration. For a better approach to improved
>stereo from 2channel sources, see Meridian's Trifield and Bongiorno's
>Trinaural processing which take their inspiration from Blumlien and
>Klipsch.
>
>Kal

Another approach is Ambiophonics which began with a nose board to prevent
crosstalk and has now developed inot a completely electronic crosstalk
cancellation system. It's very sophisticated but I've never seen a convincing
demonstration of it.

Along the topic I've also never had a satisfying demonstration of a binaural
recording with commercially produced binaural recordings or even those that
were taken live with the microphones in my own ears. Imaging is very real and
precise as long as the sound is behind my body. As soon as the sound moves to
the frontal plane I lose it and it either cannot be located or continues to
stay in the rear plane.
Anonymous
July 10, 2004 6:37:08 PM

Archived from groups: rec.audio.high-end (More info?)

We have not too long ago, rebuilt a pair of the Polk STA series
speakers, which used an interlink for each speaker to reproduce part
of the signal of the other channel. Each cabinet had a full crossover
(of very high quality I might add - This was when they still put
together a high-end quality product) and one was top operate the main
speaker and the other for a pair of drivers on each that were probably
out of phase or in some different phase relationship of the signal
from the other channel. They had been damaged from DJ use and the
interlink cable was not present, so it took some extensive crossover
work and the construction of a custom cable and pair of jacks to get
it all working again. I can't say that I liked it better with the
cables installed or just as a stereo pair. These were huge and because
of the baffle size, it may have made sense to play around with the
electronics that way to get a deeper, wider or whatever soundstage,
but it seems to have become more appearant to current designers that
limiting the baffle size or maximizing the radiating area of a
point-source driver to be a better (and more cost effective)
alternative to large arrays with complex crossovers. I think part of
the reason in that era (1980-86), was that a massive and physically
imposing speaker was almost always perceived as better, even than a
smaller design with impressive dynamics.
-Bill
www.uptownaudio.com
Roanoke VA
(540) 343-1250

"Kalman Rubinson" <kr4@nyu.edu> wrote in message
news:ccapd3026g0@news2.newsguy.com...
> On 4 Jul 2004 15:00:02 GMT, "Norman Schwartz" <nmsz1@att.net> wrote:
>
> >"Kalman Rubinson" <kr4@nyu.edu> wrote in message
> >news:fHBFc.18064$%_6.15238@attbi_s01...
> >> 2channel stereo is a compromise with phones
> >> and with speakers.
> >
> >Two channel stereo recordings with speakers does present a problem
not
> >encountered when these same recordings are heard via headphones.
These are
> >the recordings most of us listen to. IMO this problem arises mainly
because
> >some left channel *speaker* sound is perceived by the right ear and
vice
> >versa, some right channel sound enters the left ear. (Ditto for the
sound
> >reflected from room boundaries, including uncarpeted floors.) Mr.
Bob Carver
> >(a name frowned upon in audiophile circles except perhaps for his
Amazing
> >Loudspeakers, which in itself ought to prompt a hullabaloo) came
forth with
> >a device named the "C-9" hologram generator, also incorporated into
other of
> >his components) which cancels a fraction of this cross channel
perceived
> >sound, using out of phase signals fed to opposing speakers having
> >appropriate time delays. If you carefully measure distances between
the
> >sweet spot and the two speakers and then engage your pre-amps
balance
> >control; full left and R, both channels take on new dimensions
which for me
> >at least approximates headphone listening. Not, only does the C-9
serve to
> >set-up this aspect in loudspeaker listening, when employed to
maximal
> >effect, you will have set your speakers in that optimal equilateral
triangle
> >recommended for loudspeaker placement.
>
> The cancellation helps in some ways but makes for poorer center fill
> and smaller sweet spot. In addition to Carver, Polk attempted this
> with his "MARS" configuration. For a better approach to improved
> stereo from 2channel sources, see Meridian's Trifield and
Bongiorno's
> Trinaural processing which take their inspiration from Blumlien and
> Klipsch.
>
> Kal
!