Subtle surround anyone, Eno style?

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Brian Eno/Hafler were promoting surround way before our systems of today...anyone think subtle surround has merit?

These cues are easily accessed by connecting a stereo amp's +,+ terminals. (See caution below)

After all, these cues are the ONLY technical difference between mono and stereo. If you prefer stereo over mono, it follows you might prefer 3 channels over 2 channels. So, do we need commercial surround systems to enjoy surround?

The Hypothesis: you don't need discrete surround sound processing to utilize 3 distinct audio channels: Left, Right and reverberation or the so called, Third Channel. Specifically, the Third Channel is the signal difference between the stereo L and R audio channels. It's the ambience, echo, transients and spacial cues of stereo, non-existent in mono. Key here is to subtlety improve a soundstage.

The 4 potential sonic improvements of a Third Channel, without full-blown surround:
1) Enveloping 3-D, immersive soundstage. The z axis (depth) is enhanced. Some tracks are astounding. Details are enhanced. Often described as more liquid and enveloping soundstage without any processing.
2) HT or home theater are perfectly suited and are encoded for the Third channel. Obviously, the big advantage is no change of a stereo system is required when switching from HT to music.
3) Low level listening. Similar to Fletcher Munson curves, the +,+ signal is a lower level than the in-phase main speakers signals and perception of spacial cues and transients drops quickly at lower volumes. If amplified proportionately (increased), it blends well at low levels and is one of the few options to enhance spaciousness, as you decrease main L,R volume.
4) Live music sounds like the performance space. Concert hall, church or small club, these tracks flourish with an amplified Third Channel playing.

Advanced Set-Up.
It can be problematic using only one power amplifier as was advocated by Brian Eno or in the Hafler Circuit. (see below) A more sophisticated approach uses a filter to block low frequencies below 500hz, a preamp with two pre-outs with independent volume controls, a pair of mono-blocks for front channels and a dedicated stereo amplifier for the Third Channel.

Done well, 3 channel listening seems universally compatibility with all music and videos. Surround encoded is limited.

The "David Hafler surround" Hafler circuit - Wikipediaor Brian Eno third channel was popular before the multitude of discrete surround systems emerged. Bob Carver called it Sonic Holography. Paul McGowen, Spacial Audio Projector and Jim Fosgate has the SoundStage Expander...all patented products. SQ Quadrophonic systems used 4:2:4 system. But let's NOT make this thread about the history of multi-channel.

CAUTION: You've been warned! Try at your own risk. Use +,+ only with a non-bridged, negatively grounded amplifier.
 

kfbkfb

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I set up DynaQuad (again) recently, there's some clear directionality on special demo material (the QS Vector 4 demo disc, for example) and some on ordinary stereo TV content (I'm finishing up watching my Miami Vice DVDs, sometimes, some sounds in the soundtrack come mostly from the surround speaker).

Also:
(Quad with 3 speakers section)


Kirk Bayne
 

par4ken

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Brian Eno/Hafler were promoting surround way before our systems of today...anyone think subtle surround has merit?

These cues are easily accessed by connecting a stereo amp's +,+ terminals. (See caution below)

After all, these cues are the ONLY technical difference between mono and stereo. If you prefer stereo over mono, it follows you might prefer 3 channels over 2 channels. So, do we need commercial surround systems to enjoy surround?

The Hypothesis: you don't need discrete surround sound processing to utilize 3 distinct audio channels: Left, Right and reverberation or the so called, Third Channel. Specifically, the Third Channel is the signal difference between the stereo L and R audio channels. It's the ambience, echo, transients and spacial cues of stereo, non-existent in mono. Key here is to subtlety improve a soundstage.

The 4 potential sonic improvements of a Third Channel, without full-blown surround:
1) Enveloping 3-D, immersive soundstage. The z axis (depth) is enhanced. Some tracks are astounding. Details are enhanced. Often described as more liquid and enveloping soundstage without any processing.
2) HT or home theater are perfectly suited and are encoded for the Third channel. Obviously, the big advantage is no change of a stereo system is required when switching from HT to music.
3) Low level listening. Similar to Fletcher Munson curves, the +,+ signal is a lower level than the in-phase main speakers signals and perception of spacial cues and transients drops quickly at lower volumes. If amplified proportionately (increased), it blends well at low levels and is one of the few options to enhance spaciousness, as you decrease main L,R volume.
4) Live music sounds like the performance space. Concert hall, church or small club, these tracks flourish with an amplified Third Channel playing.

Advanced Set-Up.
It can be problematic using only one power amplifier as was advocated by Brian Eno or in the Hafler Circuit. (see below) A more sophisticated approach uses a filter to block low frequencies below 500hz, a preamp with two pre-outs with independent volume controls, a pair of mono-blocks for front channels and a dedicated stereo amplifier for the Third Channel.

Done well, 3 channel listening seems universally compatibility with all music and videos. Surround encoded is limited.

The "David Hafler surround" Hafler circuit - Wikipediaor Brian Eno third channel was popular before the multitude of discrete surround systems emerged. Bob Carver called it Sonic Holography. Paul McGowen, Spacial Audio Projector and Jim Fosgate has the SoundStage Expander...all patented products. SQ Quadrophonic systems used 4:2:4 system. But let's NOT make this thread about the history of multi-channel.

CAUTION: You've been warned! Try at your own risk. Use +,+ only with a non-bridged, negatively grounded amplifier.
Yes the Hafler (Dyna) speaker connection can produce very nice results on some material. I do think that four speakers are better than three though; most people don't like having a speaker placed directly behind their head. I'm sure that most if not all of the old timers here started off with this simple speaker connection but it just served to wet our appetites for real quad systems.
 

jimfisheye

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Just to be pedantic. Separating out the mono content of a stereo signal into a center speaker (or wherever you're routing any of those channels) isn't surround. Subtle surround or anything else surround! Maybe people had positive immersive-like experiences playing with it. Put the difference signal in a rear pair and that kind of thing. Maybe some stereo program came out sounding good for it. But it's not technically surround of any kind. The source material is mixed intentionally in stereo. The mix decisions are being carried out listening in stereo.

You could certainly have a surround array with 3 channels! (LRS) But for it to be surround you would need program mixed for it with a discrete surround channel. (Or an encoded system that handled that data where the surround channel was intentional.) Otherwise you're just remastering (live at playback) someone's stereo mix into a different speaker array than it was mixed for and adding your creative stamp. (Or letting some random factor add "it's" creative stamp.)

Quad is certainly enough of a surround array to get started though on that end! The 'meat' of most surround mixes - even the modern 5.1, 7.1, etc - is still usually in the 4 quad channels. A handful of mixes aside. Speaker manage the C and Lfe channels into your front L/R pair. :)

The phase trick faux surround isn't surround and you wouldn't be able to listen to any actual surround mixes and be able to reproduce the discrete channels with it at all.
 

par4ken

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Just to be pedantic. Separating out the mono content of a stereo signal into a center speaker (or wherever you're routing any of those channels) isn't surround. Subtle surround or anything else surround! Maybe people had positive immersive-like experiences playing with it. Put the difference signal in a rear pair and that kind of thing. Maybe some stereo program came out sounding good for it. But it's not technically surround of any kind. The source material is mixed intentionally in stereo. The mix decisions are being carried out listening in stereo.

You could certainly have a surround array with 3 channels! (LRS) But for it to be surround you would need program mixed for it with a discrete surround channel. (Or an encoded system that handled that data where the surround channel was intentional.) Otherwise you're just remastering (live at playback) someone's stereo mix into a different speaker array than it was mixed for and adding your creative stamp. (Or letting some random factor add "it's" creative stamp.)

Quad is certainly enough of a surround array to get started though on that end! The 'meat' of most surround mixes - even the modern 5.1, 7.1, etc - is still usually in the 4 quad channels. A handful of mixes aside. Speaker manage the C and Lfe channels into your front L/R pair. :)

The phase trick faux surround isn't surround and you wouldn't be able to listen to any actual surround mixes and be able to reproduce the discrete channels with it at all.
The Dynca diamond speaker connection was considered a surround system, it even had some recordings made for it. You could call the effect faux surround depending on the program source. Although a lot of recordings, especially live ones do contain a lot of ambience; much of which is out of phase in the left and right channels. Removing the common (in phase) information allows that ambience to be heard. Heard from the rear if that's where you placed the extra speaker(s): that's surround sound in my books!
 

LuvMyQuad

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It seems to me that most of the passive surround activity was geared toward classical and jazz listeners where the front channels provided a lot of out of phase info captured by the reflections of the performance hall and recorded in real time. The result was a more spacious stereo soundstage. It did not work well with multitracked sources, and results were often random and poor. Later, efforts were made to incorporate time delay into the scheme as well. That enhanced the effect even more, but it still didn't work well for multitracked sources.
 
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jimfisheye

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It seems to me that most of the passive surround activity was geared toward classical and jazz listeners where the front channels provided a lot of out of phase info captured by the reflections of the performance hall and recorded in real time. The result was a more spacious stereo soundstage. It did not work well with multitracked sources, and results were often random and poor. Later, efforts were made to incorporate time delay into the scheme as well. That just enhanced the effect which still didn't work well for multitracked sources.
That makes sense.

I don't mean to dismiss any of these early surround (or even faux surround-like) schemes either! Just expounding. I'm always after the shortcut to the clearest intentional sources (for good or bad). The scenic route through older tech and techniques is a fine thing. :)
 

Jim the Oldbie

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My first "surround" system was a tiny pair of Realistic Minimus-7s (remember those?) connected in series (with reversed polarity) across the 2 positive speaker terminals of my Heathkit integrated amp, perched on top of the steam pipes near the ceiling in the back corners of that first shitty little basement apartment I had after leaving home, back in 1980. It was fun! :)

A little later I breadboarded a line-level L-minus-R circuit with a dual op amp, hooked that up to the preamp outputs of the Heathkit, then ran this difference signal into an Alesis Microverb + small stereo amp. That was more funner still! :smokin

Come to think, I could pull some of this off with the existing DSP my current rig... Just do a little rerouting, flip some polarities here & there... Maybe add some delay in the back... Hmmm... :unsure:

What the hell - I'm already trying vinyl again this week for the first time in decades - might as well go full retro!
 
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Just to be pedantic. Separating out the mono content of a stereo signal into a center speaker (or wherever you're routing any of those channels) isn't surround. Subtle surround or anything else surround! Maybe people had positive immersive-like experiences playing with it. Put the difference signal in a rear pair and that kind of thing. Maybe some stereo program came out sounding good for it. But it's not technically surround of any kind. The source material is mixed intentionally in stereo. The mix decisions are being carried out listening in stereo.

You could certainly have a surround array with 3 channels! (LRS) But for it to be surround you would need program mixed for it with a discrete surround channel. (Or an encoded system that handled that data where the surround channel was intentional.) Otherwise you're just remastering (live at playback) someone's stereo mix into a different speaker array than it was mixed for and adding your creative stamp. (Or letting some random factor add "it's" creative stamp.)

Quad is certainly enough of a surround array to get started though on that end! The 'meat' of most surround mixes - even the modern 5.1, 7.1, etc - is still usually in the 4 quad channels. A handful of mixes aside. Speaker manage the C and Lfe channels into your front L/R pair. :)

The phase trick faux surround isn't surround and you wouldn't be able to listen to any actual surround mixes and be able to reproduce the discrete channels with it at all.
You're not right. I agree it's not discrete, however, surround simply means audio location cues (in this case transients, echos, spacial cues) appear to originate around you, as opposed to a defined width soundstage. Mono is a small soundstage, 2 channel stereo widened it and 3 channel surround completes the circle around the listener. The important point to note: in the original live recording these audio location cues are being captured ONLY by stereo mics. Echo's are only created by distance. In studio mixes this knowledge is used by the engineer to a greater or lesser extent to simulate "depth".

Overall, your definition of stereo is limited if you think it means 2 speakers, 2 channels only. It's limited if you think stereo only means sounds should appear to emanate from the front of the listener. Stereo is surround sound. My point is control it.

If people like descrete 5.1, 7.2, etc., it stands to reason people will prefer stereo that envelops them. No, an airplane won't appear behind them, but they will be immersed in the performance space, even studio-only mixes work. No, this isn't capital "s" Surround, but you can't hog enveloping audio.

BTW you can listen to actual Surround mixes with this set up AND rear sounds emanate from (guess where?) the rear. It's why this set up is so versatile.
 
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The Dynca diamond speaker connection was considered a surround system, it even had some recordings made for it. You could call the effect faux surround depending on the program source. Although a lot of recordings, especially live ones do contain a lot of ambience; much of which is out of phase in the left and right channels. Removing the common (in phase) information allows that ambience to be heard. Heard from the rear if that's where you placed the extra speaker(s): that's surround sound in my books!
Yep, totally agree. I cringe at calling it, "faux surround" however. Surely stereo is the Orginator and deserve respect.
 

fizzywiggs41

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Brian Eno/Hafler were promoting surround way before our systems of today...

Done well, 3 channel listening seems universally compatibility with all music and videos. Surround encoded is limited.

The "David Hafler surround" Hafler circuit - Wikipediaor Brian Eno third channel was popular before the multitude of discrete surround systems emerged. Bob Carver called it Sonic Holography. Paul McGowen, Spacial Audio Projector and Jim Fosgate has the SoundStage Expander...all patented products. SQ Quadrophonic systems used 4:2:4 system. But let's NOT make this thread about the history of multi-channel.

CAUTION: You've been warned! Try at your own risk. Use +,+ only with a non-bridged, negatively grounded amplifier.

I assume you've read this from:" Brian Eno's -Ambient 4 On Land " album from 1982.
 

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fizzywiggs41

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@JimofMaine

There's also this listing of David Hafler's Recommended Dynaquad stereo recordings ...........BTW
(fr/ Ken Sessions book--"4 CHANNEL STEREO ......From Source To Sound" Tab books #756 )



[ fwiw there is a thread in the Quadraphonic matrix albums section ]
:)
 

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MidiMagic

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Since July 1970, I have never been without this.

- First I built the Dynaco diamond.

- I encoded sound effects for a stage play, played back in the theater on the Dynaco Diamond. The play was in February 1971.

- I have the Dynaco demonstration record. That is deliberate.

- The EV Demonstration record plays correctly through it.

- Then I built a 4-corners decoder placed after the amplifier:

uq-1-o.gif


I still have one in use. Two more are in storage (I had one in my office at work before I retired).

It can decode any of the RM matrix formats (DS, QS, EV, DQ, and DD) by adjusting the WIDTH and DEPTH controls to match the matrix parameters.

I get the LRS by turning WIDTH and DEPTH all the way up.

It can decode any of the RM matrix formats with the LRS setting. The sounds are in almost the correct places played this way. So any RM encoded record is "deliberate" as far as LRS is concerned.

I actually prefer this to discrete. Whenever I hear discrete quad that is not carefully mixed to avoid this effect, I hear 4 puddles of sound at the speakers.
 
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MidiMagic

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@MidiMagic

What did you use for an Encoder for Dynaquad ?
Originally I used what I had.

I had a cheap "stereo" mixer that had 4 inputs and two outputs. There were 8 knobs - one for the amount of each input in each output.

I also had a 1952 mono preamp for a hi-fi (which I bought for the record compensator for older records). The last stage (between the AUX input and the output) reversed the phase (not important in mono systems).

I connected them in this manner:

qmixmixr.gif


This let me position any two sounds in any position in the Dynaco Diamond.

I used the oscilloscope in X-Y mode to observe the encoding angle.

I now use this method for any RM encoding:

encodt2.gif


It is put in sub inserts 3 and 4 of any 4-sub mixer.

livehous.gif

This is an image I already had. But it can encode recordings as well as a house mix.

Select the main buses for IN, and the 3-4 buses for OUT for each channel strip.
Turn the pan control to move left or right in each case. This diagram is for Dolby Surround/PL-I/PL-II.

surrpand.gif
cstrip.gif

A sample channel strip portion is shown. The SUB 3/4 button connects the strip to 3/4 instead of 1/2.
 
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MagnumX

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I'm rather off-put by the notion I'm reading above by at least one person that something isn't "surround" because it's not a specific format or even worse that it doesn't seek the mixing engineer's "intent". If you're going to follow the latter, you better get the same room, same speakers and even the same amps so you can hear exactly what the mixing engineer heard lest one commit heresy!

What is Sonic Holography or Ambisonics or the Surround Master or Pro Logic IIx or Auromatic or DSU or even using dipole front speakers if not all ways to enhance sound/music in ways that one might find more engaging or realistic sounding than what mere stereo can offer? You can argue about intent, but is some predefined notion the best representation of an artist's music? If it is, why would any of us buy 5.1 or Atmos mixes of the same album (often mixed or remixed by someone else?) IMO, music should be about enjoyment and if it's not enjoyable, it's a waste of precious time and life.

I'll listen to an album in stereo. I'll also try it with Sonic Holography on my Carver system and numerous surround formats on my home theater system. I even have an arrayed 6-channel stereo mode (using L/C/R + Front Wides + Front Heights for dialog lift) that cancels out some side and ceiling reflections and perhaps even a bit of crosstalk as it sounds oddly similar to Sonic Holography despite using no processing other than an active mixer.

If I'm not enjoying myself, I'll go do something else. I certainly don't need someone to tell me I'm listening to something wrong.

So in that sense, I think people should experiment all they want with Brian Eno/Hafler methods or anything else they want to try out. Maybe even headphones! (OMG!) :unsure:
 

newslane

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I'm rather off-put by the notion I'm reading above by at least one person that something isn't "surround" because it's not a specific format or even worse that it doesn't seek the mixing engineer's "intent". If you're going to follow the latter, you better get the same room, same speakers and even the same amps so you can hear exactly what the mixing engineer heard lest one commit heresy!

What is Sonic Holography or Ambisonics or the Surround Master or Pro Logic IIx or Auromatic or DSU or even using dipole front speakers if not all ways to enhance sound/music in ways that one might find more engaging or realistic sounding than what mere stereo can offer? You can argue about intent, but is some predefined notion the best representation of an artist's music? If it is, why would any of us buy 5.1 or Atmos mixes of the same album (often mixed or remixed by someone else?) IMO, music should be about enjoyment and if it's not enjoyable, it's a waste of precious time and life.

I'll listen to an album in stereo. I'll also try it with Sonic Holography on my Carver system and numerous surround formats on my home theater system. I even have an arrayed 6-channel stereo mode (using L/C/R + Front Wides + Front Heights for dialog lift) that cancels out some side and ceiling reflections and perhaps even a bit of crosstalk as it sounds oddly similar to Sonic Holography despite using no processing other than an active mixer.

If I'm not enjoying myself, I'll go do something else. I certainly don't need someone to tell me I'm listening to something wrong.

So in that sense, I think people should experiment all they want with Brian Eno/Hafler methods or anything else they want to try out. Maybe even headphones! (OMG!) :unsure:

Magnum...consider joining our new Carver Sonic Holography Facebook group.....

 

jimfisheye

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I'm rather off-put by the notion I'm reading above by at least one person that something isn't "surround" because it's not a specific format or even worse that it doesn't seek the mixing engineer's "intent". If you're going to follow the latter, you better get the same room, same speakers and even the same amps so you can hear exactly what the mixing engineer heard lest one commit heresy!

...
I don't want to speak for someone else...

I've made comments about the distinction between a mix as intentionally delivered by an artist vs the end consumer altering it with their own remastering. I've done the latter before and certainly will again! (Stinky opinions and all, you know.)

I think it's important to recognize and at least listen to the original mix as intended. Following that, there's a distinction between an original mix vs random effects from some kinds of upmix style processing. I might find I like someone's upmix better than someone else's original intentional mix. I just want to hear the original first (for good or bad) and acknowledge intentional work.

That's where my comments that resemble that come from. :)
It's like watching someone salt some food you made before tasting it.

There's really a lot of grey area in between with some of the early creative surround concepts and approaches! This very system mentioned here appears swings both ways. It looks like there was material created specifically to work with it intentionally (as well as the system made possible) as well as it being an interesting effect for stereo mixes where the treatment was never considered ahead of time.
 

MidiMagic

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Want to talk about deliberate?

Almost all of the TV programs I watch are in surround sound (using PL-II).

So are many of the commercials. Mostly the local commercials are in mono.

And I even hear a few surround commercials on FM radio (though most of the music is just stereo).
 
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