Speaker position now driven by video, not audio, let's face it...

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~dave~~wave~

2K Club - QQ Super Nova
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Exhibit A, 50 years ago:


IMG_7268.JPG





Exhibit B, today:


Screen Shot 2022-04-08 at 7.58.41 AM.png



What the heck?

What ever happened to proper stereo speaker placement, for a start?
Equilateral triangle of speakers and sweet spot, align toe-in for phantom center?

What started me down this path is listening to Atmos streams through speakers and comparing their "spatial" headphone renderings.
Then a vintage "wide stereo" mix.

I know the pushback on spatial headphone is going to be "big deal, sounds like wide stereo."

Well, for people sitting in a home theater layout like Atmos suggests in this diagram, what in the hell are they hearing?
It looks like three-point audio to me.
Narrow front, wide sides, "rear" speakers so close as to be useless for anyone seated outside the sweet spot.



Screen Shot 2022-04-07 at 3.42.08 PM.png


Some of the highest rated "surround" titles in the polls are vintage quad.
How do those mixes translate to a setup like the above?
@edisonbaggins apparently gave up on compromising to try to make home theater work properly for quad, and has separate rooms for quad and Atmos.

Modern mixes seem to have narrowed the front stereo sound field to approaching mono, leading to couples happily sharing earbuds.


1649425659081.png



Headphones sound field never matches speakers in a room unless
  • the mix is panned to the center, or
  • a listener at home moves his speakers from front to sides
Kindly help me process all this with your experiences and observations.


:51QQProper speaker layout & sweet spot for 5.1 Audio. One man's opinion, agree or disagree.
 
The real conundrum is that the 70's quads were mixed for A systems, while modern 21st century 5.1s are mixed for B systems. The one adjustment I have made for the purpose of listening to 70's quads is to to put speakers with a fuller range in the back (OK side surrounds). They still bottom out at 60 Hz, but that's way better than the 120Hz I had before. Having bass come from the rear isn't nearly as ridiculous. With modern mixes bass almost always come from the front so it's not an issue.
 
Exhibit A, 50 years ago:


View attachment 77671




Exhibit B, today:


View attachment 77672


What the heck?

What ever happened to proper stereo speaker placement, for a start?
Equilateral triangle of speakers and sweet spot, align toe-in for phantom center?

What started me down this path is listening to Atmos streams through speakers and comparing their "spatial" headphone renderings.
Then a vintage "wide stereo" mix.

I know the pushback on spatial headphone is going to be "big deal, sounds like wide stereo."

Well, for people sitting in a home theater layout like Atmos suggests in this diagram, what in the hell are they hearing?
It looks like three-point audio to me.
Narrow front, wide sides, "rear" speakers so close as to be useless for anyone seated outside the sweet spot.



View attachment 77674

Some of the highest rated "surround" titles in the polls are vintage quad.
How do those mixes translate to a setup like the above?
@edisonbaggins apparently gave up on compromising to try to make home theater work properly for quad, and has separate rooms for quad and Atmos.

Modern mixes seem to have narrowed the front stereo sound field to approaching mono, leading to couples happily sharing earbuds.


View attachment 77673


Headphones sound field never matches speakers in a room unless
  • the mix is panned to the center, or
  • a listener at home moves his speakers from front to sides
Kindly help me process all this with your experiences and observations.


:51QQProper speaker layout & sweet spot for 5.1 Audio. One man's opinion, agree or disagree.

My sweet spot is much like Exhibit A. All speakers are equidistant from my listening chair, carefully matched toe in and distance. Before video I did it this way to control arrival times from each speaker as close as possible. I always knew side center imaging was a challenge at best and this speaker layout would do the least damage any further to side sounds.

Now Exhibit B is also accurate for my set up. I have a couch is directly in between the rear speakers. My sweet spot chair is forward of that, in the middle. When I sit on the couch it's very much as you describe: quite a wide left/right presentation in the rear with a noticeably contracted width in the front. In regards to the B illustration, I would certainly suggest moving the front speakers wider apart to at least 45 deg. I mean, if it's home theater, people will probably be using a center front speaker. May as well get some need L/R expansion up front.

FWIW, yes I do have center front speakers. They are 6.5" 2 way. One hanges inverted from the ceiling aboube the screen, one sits on the floor below the screen. Like the corner speakers they measure exactly the same to a mike stand as reference in the sweet spot epicenter. In practice they blend to gether so it doesn't sound like audio is coming from the floor or ceiling. Optional indeed for music but comes in handy for movies if people are scattered about the room.
 
I used to have to an SQ "A" system back in the 70's. When I first set up a home theater system 20 years later I put rears behind the couch because I just assumed that was the way to do it. Eventually I learned the difference between side and rear surround speakers. Now I have a 5.2.2 system with the couch against the back wall - no way to have rear surrounds. Definitely a "B" system. The other thing about "B" systems is that the receivers adjust the signal for distance from the sweet spot. I presume that makes speaker placement somewhat less crucial.
 
The real conundrum is that the 70's quads were mixed for A systems, while modern 21st century 5.1s are mixed for B systems. The one adjustment I have made for the purpose of listening to 70's quads is to to put speakers with a fuller range in the back (OK side surrounds). They still bottom out at 60 Hz, but that's way better than the 120Hz I had before. Having bass come from the rear isn't nearly as ridiculous. With modern mixes bass almost always come from the front so it's not an issue.

Appreciate your input.
Absolutely concur with bigger or deeper-range "rear" speakers, for vintage quad especially.

Listening to the new Grammy-winning Jon Batiste Atmos in 5.1, delighted that drums are banging from all four corners
(Wherever those corners land in a given room, as everything is a compromise in the real world.)
May this style of mix never completely fade into history.
 
This is my layout and it works great for all purposes - 4.0 quad, 5.1, 7.1, 7.1.4 Atmos, music, movies, you name it. It's kind of a hybrid of the OP's original 2 diagrams - maintains the equilateral triangle in the front, a bit wider in the rears for 4.0 but still equidistant. The fronts are towers and the surround speakers are more bookshelf sized, but with bass routed to the subwoofer, I don't feel like anything is lacking at all.

1649432541781.png
 
The problem with exhibit A is it's not easy to fit into a typical listening room. I've long favored something closer to the B example. Pull those side speakers back a bit, toe them in slightly if they seem too loud. Most setups for home theater show the fronts and centre awfully close together. I would pull them apart a bit but not so much as to create hole in the middle stereo. I don't get the fashion of specifying angles as modern depictions almost always do. To add those speakers behind you need a deep room, OK for a specially designed home theatre, not so practical in a typical living room.
 
Mine was actually set up like Exhibit B until AFTER the release of Bonana, when I realized Exhibit A makes for a much nicer sound presentation when I was tinkering with settings.
I always saw people set it up like Exhibit A around here, which I blame on the local AV shops doing their best to misinform.
At least I have a burning anger against satellite speakers, which most of my peers don't have.
 
The set up suggested by Lafayette (1st image)is closest to my preferred set-up for quad. Also shown are some other
slight variations from Audionics and from CBS from the back cover of the "New Quadraphonic Gala" Demonstration record.
Thanks for sharing the vintage diagrams, especially the final image in green.
Words of wisdom we can all agree on regarding practical compromises & value of experimentation for optimum results.
Which are individual and personal, not a mandatory template.
 
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...The other thing about "B" systems is that the receivers adjust the signal for distance from the sweet spot. I presume that makes speaker placement somewhat less crucial.

An important point & major advance in technology.
Certainly makes experimenting with layouts & placement more an adventure, less a chore.
 
The rears in 4.0 can be towed in to 115 deg instead of 135 deg to the listeners preference just the same as in 5.1. Or... you can go with 135 deg in 5.1 if you prefer. Everything else follows. All speaker to listening position distances are equal. Quad never went away. It's the meat of a 5.1 mix!

Some of those diagrams above are skewed by artistic license or something. The ones appearing to show wildly different distances from different channels to the listening position.

You're not wrong that this setup has a "front" though! Quad could be setup "4 corner" and had some mixes that had an ambiguous "front". I still feel like these come across as intended by the mix engineer with towed in rears.

The biggest thing to watch out for are AVR features that make grossly incorrect setup seem like a reasonable option! Placing speakers different distances from the listening position and introducing delays in the shorter length channels to normalize it is the big no no. That would limit the listening position to a very small sweet spot and you'd have the clatter of delayed reflections around you.
 
How is the Atmos diagram showing 'narrow' front ? Toe-in is shown on all the diagrams.

There is also other research on this topic -- see Floyd Toole's book. (Specifically, Chapter 15 of the 3rd edition)


For example:

1649443075217.png
 
The biggest thing to watch out for are AVR features that make grossly incorrect setup seem like a reasonable option! Placing speakers different distances from the listening position and introducing delays in the shorter length channels to normalize it is the big no no. That would limit the listening position to a very small sweet spot and you'd have the clatter of delayed reflections around you.

Delays are pretty crucial, and there is nothing inherently wrong with rear speakers being a different distance from MLP than fronts.
 
How is the Atmos diagram showing 'narrow' front ? Toe-in is shown on all the diagrams.

Thanks for chiming in.

Below is the official Atmos 5.1 layout map.
It looks "narrow" front to me because the stereo rule of thumb I grew up with was an equilateral triangle.
Equal distance between the speakers as from each to the sweet spot.

It appears the sofa is pushed back in the room to accomodate the over-sized video screen, not for optimum listening.
If it was closer to the front, the sound field would be wider?

Curious what a vintage quad "circular" pan sounds like in this diagram, regardless of delay calibration and toe-ins?
Is this what's driving the move to seven or nine floors speakers, when four used to be enough?



Screen Shot 2022-04-07 at 3.47.08 PM.png


The note on your attachment says it's modeled on large halls, not home living / rec rooms.
Perhaps you might summarize how the references you cited apply to the A / B examples?
 
Thanks for chiming in.

Below is the official Atmos 5.1 layout map.
It looks "narrow" front to me because the stereo rule of thumb I grew up with was an equilateral triangle.
Equal distance between the speakers as from each to the sweet spot.


It appears the sofa is pushed back in the room to accomodate the over-sized video screen, not for optimum listening.
If it was closer to the front, the sound field would be wider?

And how does that differ from the old quad diagrams accompanying it? The first schematic just recommends separating the fronts by 6-8 feet. They do not appear to be arranged as an equilateral triangle with the couch, nor is it specified in text. Ditto the other two schematics. . And even traditional stereo as I recall accommodated a range of angles in the user manuals that accompanied loudspeakers.



Curious what a vintage quad "circular" pan sounds like in this diagram, regardless of delay calibration and toe-ins?
Is this what's driving the move to seven or nine floors speakers, when four used to be enough?


Vintage quad circular pans in my 5.2 system sound....circular.

The note on your attachment says it's modeled on large halls, not home living / rec rooms.
Perhaps you might summarize how the references you cited apply to the A / B examples?

The note refers to the sound field being reproduced by the multichannel system. The performance space, not the playback space. E.g., in the case of b,c,d, it would be like testing how well the sense of the concert hall space captured in a concert recording, is conveyed by the multichannel playback configuration.
 
Last edited:
My setup is aprox Exhibit “B”.

I have tried to locate all equidistant, buy my MLP is a bit behind the geometric center.

I have full range speakers for Surrounds (side) and Surrounds Back.

When listening to Quad, original 70’s Quad or upmixed stereo with Surround Master V3, I have to trim down a little the side surrounds level, for some mixes.

I have two alternatives, that use to change from time to time:

- For some Quad mixes, the rear speakers (side surrounds) generate a kind of binaural “into my head” effect that I like, although it hides a little the front sound.

- For other 70’s Quad mixes I re-assign the Side Surrounds to the Surrounds Back, and get “almost” a speaker's square. That sound more balanced for some mixes.
 
My two cents. Whatever works for an individual household is better than just stereo or a shitbar. However, I criticize this specific Exhibit B layout shown below because it should come with a caveat: Those side surround speakers aligned at 90 degrees should be moved back a bit (i.e. 110 deg) unless they are installed above the listeners' head levels. If not installed above head level, the sound coming from the side surrounds will be blocked by a someone's head if there are multiple listeners.

1649507457834.png


And as for this:

1649507727946.png


Oh PUKE!
 
My setup is aprox Exhibit “B”.

I have tried to locate all equidistant, buy my MLP is a bit behind the geometric center.

I have full range speakers for Surrounds (side) and Surrounds Back.

When listening to Quad, original 70’s Quad or upmixed stereo with Surround Master V3, I have to trim down a little the side surrounds level, for some mixes.

I have two alternatives, that use to change from time to time:

- For some Quad mixes, the rear speakers (side surrounds) generate a kind of binaural “into my head” effect that I like, although it hides a little the front sound.

- For other 70’s Quad mixes I re-assign the Side Surrounds to the Surrounds Back, and get “almost” a speaker's square. That sound more balanced for some mixes.
Thank you, sir, for a very informative contribution. :bowing:

As a 5.1 listener who has read about some of the challenges and quirks of Quad listening as 7 or 9 floor speakers come into play, this is most welcome.
(I didn't relish the thought of trolling through hundreds of old posts to dig out a related comment)

The newest Surround Master observation is icing on the cake.
 
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