Controlled vs wide dispersion in a normal living room environment..

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After years of being frustrated with my loudspeaker/ living room interface, I have come to the conclusion that wide(or even moderately wide) dispersion loudspeakers are not a good thing in untreated "normal" living rooms.
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All the wide dispersion speakers sounded that way unless they had sidewall treatment.
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If you can't treat the room(As in wife?), do whatever else you can to bypass it( i.e., by controlling dispersion)..(By the way,this post is meant mainly for newbies)

newbies - don't be misguided!

it is just Remlab's subjective opinion based on some unfortunate bad experience

from extensive research which Floyd Toole summarizes in his book "Sound Reproduction: Loudspeakers and Rooms" (2008) it follows that sidewall treatment is exactly the last thing desirable in a stereo setup

most informed people agree that we need side reflections in room for a stereo recording to sound satisfactorily - realistically

the only disagreement is that some claim - as Toole or Moulton for example - that we most need early, 1st order sidewall reflections and others - like Gedlee or Speaker Dave here on the forum for example - that we rather need later refections especially from wider angles from the back

if You want to follow the latter recommendation then You need highly directional speakers and front and rear wall treatment - but not absorption but diffusion and deflection

if you want to follow the former - You need not just any "wide dispersion" speakers, but controlled "wide dispersion", preferably horizontally omnidirectional

only if You have "moderately wide" speakers, then perhaps You need sidewall's treatment but You will not get the best stereo sound anyway
 
But what produces realism depends on one's experience, and the 'taste' of one's ears.

utter nonsense, we are all humans and have human sense of hearing, requirements for realism follow from physiology of hearing

For the "average" person, i.e., not an audiophile listening critically, when an instrument or singer isn't as loud as they're supposed to be (which we can judge from cues in the recording), we tend to look for cues in the environment that explain why, the most likely culprit being distance. If there's enough reverb in the room to make the performer sound far enough away to explain the lower level, then one's brain relaxes and says, "Okay, that's realistic".

average vs audiophile?

I am with Linkwitz: "Unbiased listeners have no difficulty recognizing accurate sound reproduction, even with hearing damage or with hearing aids"

I know it may seem I'm being a bit contrary here, but despite all the theory, studies and blind tests, etc., I think to a great degree it's just a matter of personal preference. And to the newbie that Remlab addresses in the OP, I agree. Don't get caught up in the quest for wide dispersion if you can't/haven't/won't treat the walls of your room.

You disregard "theory, studies and blind tests" because Your personal preference happens to be different? this is pure silliness
 
from extensive research which Floyd Toole summarizes in his book "Sound Reproduction: Loudspeakers and Rooms" (2008) it follows that sidewall treatment is exactly the last thing desirable in a stereo setup

most informed people agree that we need side reflections in room for a stereo recording to sound satisfactorily - realistically

the only disagreement is that some claim - as Toole or Moulton for example - that we most need early, 1st order sidewall reflections and others - like Gedlee or Speaker Dave here on the forum for example - that we rather need later refections especially from wider angles from the back

if You want to follow the latter recommendation then You need highly directional speakers and front and rear wall treatment - but not absorption but diffusion and deflection

if you want to follow the former - You need not just any "wide dispersion" speakers, but controlled "wide dispersion", preferably horizontally omnidirectional

only if You have "moderately wide" speakers, then perhaps You need sidewall's treatment but You will not get the best stereo sound anyway

I, and most research in the area, agree with this. The further you move from a "perfect" horizontally omni-directional speaker toward controlled dispersion, the more room treatment and care in regards to placement you need. A horizontally omni-directional speaker is contrary to popular belief by ill-informed people not critical about room placement, at least not compared to a narrow directional monopole or dipole speaker.
 
I, and most research in the area, agree with this. The further you move from a "perfect" horizontally omni-directional speaker toward controlled dispersion, the more room treatment and care in regards to placement you need. A horizontally omni-directional speaker is contrary to popular belief by ill-informed people not critical about room placement, at least not compared to a narrow directional monopole or dipole speaker.

Not critical to placement? What happens when you place such a speaker asymmetrical, i.e. sidewall reflection of one speaker is louder and arrives earlier than sidewall reflection of the other speaker? In my experience it skews imaging and perceived spaciousness by a great amount. The same is true for nearby objects/boundaries that create asymmetrical reflections. In typical living rooms nearly every object is near by.

Furthermore, when the speaker has only wide horizontal dispersion but doesn't create any strong reflections from elevated locations (no or low vertical dispersion), I found that the sound stage gets horizontally squashed.
 
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For the "average" person, i.e., not an audiophile listening critically, when an instrument or singer isn't as loud as they're supposed to be (which we can judge from cues in the recording), we tend to look for cues in the environment that explain why, the most likely culprit being distance. If there's enough reverb in the room to make the performer sound far enough away to explain the lower level, then one's brain relaxes and says, "Okay, that's realistic".

That's an important point. Often people only look at D/R ratios but forget that absolute SPL is also a factor in how D/R ratios are perceived.
 
utter nonsense, we are all humans and have human sense of hearing, requirements for realism follow from physiology of hearing
And when you learn more about the physiology and psychology of hearing, perhaps you'll better understand why we don't all share the same perception of a single thing. I remember an article by a Japanese luthier in Chicago, bemoaning the difficulty he had in pleasing his American clientele because he was raised in a culture that enjoyed dissonance, rather than consonance. I remember a lot of things. I remember that when I started this journey, everything was monophonic, and "more realistic reproduction" was a realistic and attainable goal. These days, how do you make a vocoder more realistic?

Professionally, I have built loudspeakers, recording studios, and home theatres. I have interviewed thousands of people listening to hundreds of speakers in hundreds of environments. When I suggest that people hear things differently, and different things please them, it's not just something I read somewhere.


You disregard "theory, studies and blind tests" because Your personal preference happens to be different? this is pure silliness
I realise English may not be your first language, but that's not at all what I said. You may want to reconsider your understanding of Toole's work. You are quite adamant on several points, but as I recall, Toole tempered his conclusions with many modifiers.
 
I, and most research in the area, agree with this. The further you move from a "perfect" horizontally omni-directional speaker toward controlled dispersion, the more room treatment and care in regards to placement you need. A horizontally omni-directional speaker is contrary to popular belief by ill-informed people not critical about room placement, at least not compared to a narrow directional monopole or dipole speaker.
This is, in essence, the principle by which Dr. Bose created the 901s. It works well for close-mic'd acoustic instruments, as they are generally omni-directional in nature. It doesn't work as well for modern recordings with a synthetic soundstage. Now, you may well argue that the average person has never sat at a recording console, and has no idea what the producer heard when he approved the mix, but then, when you ask them about "realism"... you may as well ask them "What color is a unicorn's horn?", no?
 
Toole tempered his conclusions with many modifiers.

Quite correct. I don't know where people get this from that Toole would favor omni-like designs. If one follows Toole's recommendations then we end up with low reverberation levels. The only difference is that he advocates side reflections to increase spaciousness.

His recommendations sound more like he's trying to make LEDE work for multichannel:

add sound absorbing material to front
wall.

for stereo listening, leave side walls
reflective at first-reflection points. For multichannel listening it is optional. Audio
professionals may have their own preferences—it’s all right, they are just different.

add sound absorbing material or
diffusers to center portion of rear wall.

use reflecting or scattering surfaces on
walls opposite side-surround loudspeakers to enhance envelopment. Be careful
about flutter echoes between the side walls.

think twice (or more) about using dipole
surround loudspeakers. There seem to be better choices.
 
i couldnt agree more Markus and Keriwena. My experience of omnis isnt good, and as you say, there are many reflections. In my listening room, it is quite easy to notice the splashback from walls, if the speakers are too close to boundaries, or one is sinificantly closer to a boundary or other object. The effect is quite disturbing. Like wise ceiling reflections are troublesome, i have large 45degree ceiling sections, and this makes matters worse again. Damping rear wall and listening in a compact triangle is the only method i found effective. With horns or Cd devices id expect the same, albeit requiring a larger listening triangle.
 
And when you learn more about the physiology and psychology of hearing, perhaps you'll better understand why we don't all share the same perception of a single thing. I remember an article by a Japanese luthier ... a vocoder ...
I beg Your pardon - what´s the point?
When I suggest that people hear things differently, and different things please them, it's not just something I read somewhere.
so You did scientific research?

that's not at all what I said. You may want to reconsider your understanding of Toole's work. You are quite adamant on several points, but as I recall, Toole tempered his conclusions with many modifiers.
then what did You say? Can You clarify please? What modifiers? We discuss stereo speakers, right?
 
Graaf
Floyd's room(He is obviously not an audiophile.)
Advice From an Audio Insider | Home Theater
Could you imagine what 2 channel, wide dispersion playback would sound like in this room? This is exactly what I'm referring to as " a normal living room." Are you telling me that a narrow dispersion 2 channel speaker would actually sound worse than a wide dispersion 2 channel speaker in this setup? Surely you must be joking..
 
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What I actually said was:
I know it may seem I'm being a bit contrary here, but despite all the theory, studies and blind tests, etc., I think to a great degree it's just a matter of personal preference.
It's not my personal preferences I'm addressing, but the listeners.

My point, and I do have several, is this:

Since the advent of multi-track recording (thank you, Les Paul!) and electric/electronic instruments dominating popular music, there is no longer a "reality" to be achieved. While in a gross sense, we don't want speakers that make Beyonce sound like Lois Armstrong, the finer points like the space around the drums and the tone of the guitar can only be imagined. Thus, their "proper" rendition becomes a matter of personal preference.

While agreement on these preferences is possible, it will be influenced by the similarity of the perceptions of the listeners. For some people, flat response is a prerequisite, and any deviation from this is intolerable. Others are more impressed by dynamic range, and will gladly suffer response curve anomalies in the search for a lack of compression. Yet another group prizes freedom from distortion. A system which delivers all of these attributes will be lauded by all, but the reality is that speakers are a compromise, and the choices of compromise will define the perception of the speaker's quality based on preferences of the listeners.

To suggest, as you have done:
newbies - don't be misguided!

it is just Remlab's subjective opinion based on some unfortunate bad experience

from extensive research which Floyd Toole summarizes in his book "Sound Reproduction: Loudspeakers and Rooms" (2008) it follows that sidewall treatment is exactly the last thing desirable in a stereo setup

most informed people agree that we need side reflections in room for a stereo recording to sound satisfactorily - realistically
that a person's personal preferences are wrong because they contradict your interpretation of an author's conclusions is...

well, rude, to say the least.


BTW, Floyd's actual statement:
In conclusion, it seems that the basic audible effects of early reflections in recordings are well preserved in the reflective sound fields of ordinary rooms. There is no requirement to absorb first reflections to allow recorded reflections to be heard.
does not imply there's something wrong with absorbing first reflections, he merely claims it's not necessary. Seems to me you've made an incredible leap of faith to decree that room reflections are required. And yes, the religious analogy is intentional. You seem to be elevating Dr. Toole to some god-like status. He's merely the first, perhaps, to assemble a body of data, and historically may prove to be as wrong as....

oh, never mind, I'm not going to start a religious war, here. Suffice to say there was another "Dr. T" who oversimplified things and claimed the glory while others, often unnamed, spent decades sorting out his mess. :D
 
One can always mix different types of speaker into one system. Just take the characters as the building blocks.

DSCF6143.jpg


Overall a 3-ch linear matrix:

Central channel: DML panel above 80(or 100)Hz, nearly omni itself but very close to the wall, thus half space eventually. Dipole bass, also near wall, so the rear lobe becomes sort of side firing.

Side channels: Dipole mid-array for (200~3kHz), flooder tweeter (omni above 3kHz), dipole bass.

The room is very reflective. Acoustical treatment is almost non-existent.
 
One can always mix different types of speaker into one system. Just take the characters as the building blocks.

DSCF6143.jpg


The room is very reflective. Acoustical treatment is almost non-existent.

I agree. It looks extremely reflective, heh. Very nice though! Solid birch panels?

As for dispersion angles, especially of tweeters, I absolutely hate it when they are so narrow (like laser beam narrow) as to create a one single stereo sweet spot that if you're not sitting in it, you're not hearing anything good. However, the opposite is also true for me. Too wide blurs it to the point of relative nonexistence. So "pick your dispersion angle poison" and live with who gets to sit where and hear the best quality!

I had an excellent listening room long ago with two two-way (mid/woofer & tweeter) speakers 18 feet apart, hung in each upper corner of the back wall (ie sound wall) firing at an angle inward and downward towards my couch on the opposite wall which was 14 feet away (measured not from each speaker but the room's back wall to my couch wall measured). Ceiling height was about 8 feet I think. Each speaker was around 1.0 cuft, weighed a ton (home made in the 70's), and front ported. Tweeters were horn type, mids were around 6.5" with whizzer cones (haha). I fed them around 200Hz upwards. Then two large woofers (didn't have money for nice subwoofers back then) on my wall with the couch, 18 feet apart but firing directly at me from each corner along the back wall. They got the lower signals from a second amplifier that I piggybacked in a half-*** manner (but it worked!).

To this day, I believe it was the very best setup I've ever experienced. Yes, there is some nostalgia there, like hearing Pink Floyd's DSOTM for the first time (and then 100's of more times after that), but those mid/woofer & tweeter speakers STILL sound wonderful (they just cannot handle as much power anymore). Kraftwerk (Autobahn) with the highs flying between the left and right of the room sounded awesome with the woofers going as low as they could go. Lots of fun back then.
 
As for dispersion angles, especially of tweeters, I absolutely hate it when they are so narrow (like laser beam narrow) as to create a one single stereo sweet spot that if you're not sitting in it, you're not hearing anything good. However, the opposite is also true for me. Too wide blurs it to the point of relative nonexistence. So "pick your dispersion angle poison" and live with who gets to sit where and hear the best quality!

If you can get a constant 90 degree pattern, and then cross-fire, you don't have to pick your poison at least from an imaging perspective.

The only drawback is the other stuff discussed in this thread.
 
... Very nice though! Solid birch panels?
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Thanks for the kind words. They are just ready-made cheap pine boards. The ready-made sizes also saved me a lot of cutting:D (I finally realized a while ago that in this hobby I'm inevitable in the status of 'in the journey', so I think I'd better be lightly packed.)

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About the setup of large toe-in (cross-fire), it solves some of the problems but can not side step the issue of incorrect pinna cue in HF. There're quite some related psychoacoustics discussions here somewhere, and I'm not an expert, so no further comments.

Nevertheless I'm very happy with this 3-ch setup with wide-spreading HF and central channel, and side channels with narrow dispersion (except HF).
 
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