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

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What I actually said was:

It's not my personal preferences I'm addressing, but the listeners.

which listeners? because You named only Yourself in Your post:

I get that some people expect to hear the room, as that is their experience. In my case, it's not.


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.

believe me or not this subject was discussed numerous times here and to such a worn out argument it suffices to reply with a simple question: Did we cease to play acoustic intruments "since the advent of ... electric/electronic instruments"? Or - did we stop going to unamplified concerts since "the advent of multi-track recording"?

There is the reality and the measure, listen to children singing and there You get it. There it is and there is no other.

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.

"their" - yes, but this is not the whole thing, rather these are marginal cases indeed, the world is muuuuch bigger than pop culture

To suggest, as you have done:

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.

well, it's pretty rude and also unfair to suggest that I have done something I haven't

because nowhere I have suggested that Remlab's "personal preferences are wrong"
BTW this would be utter nonsense as preferences just CAN'T "be wrong"

I only have suggested that making a general statements and especially "advices for newbies" purely out of such personal preferences is not right. And please tell me - do You sincerely believe it is?

what is also pretty rude is to write things like "when you learn more ... perhaps you'll better understand", don't You agree?

BTW, Floyd's actual statement:
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.

to suggest that I misuse Toole's book as a reference is rude too, don't You agree?

hereby I post a scan of Toole's concluding statement on the subject of sidewall reflections

look Keriwena, You are a highly experienced professional, to me You just seem to be profesionally biased, please consider the advice Toole gives to professionals in the scanned fragment of his book posted below - Your preferences, and preferences of Your colleagues may just reflect "accumulated biases", You may just be abnormally oversensitized to some aspects of sound, it is a sort of an "occupational disease", but please don't feel sorry because as Toole points out - "it's all right", You preferences are "just different", there is nothing wrong with them or with You :)


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....

I seem? :rolleyes:

You may be surprised but it is actually pretty funny what You say because I only refer to Toole in these discussions because some other people here elevated him "to some god-like status" in discussions with me here couple of years ago, apparently without actually reading the book, or at least without reading it with any understanding :rolleyes:

and they stop elevating him only after they discovered that "the body of data" he presents in the book in fact falsifies "several points" they were (and still are) "quiet adamant on" ;)

now his book is only "a body of data" ;) but they still look silly
 

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One can always mix different types of speaker into one system. Just take the characters as the building blocks.

...

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.

very nice! :cheers:

where exactly are those flooder tweeters?
 
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..
Graaf
Another thing about Dr. Toole. He is anti "stereo" reproduction, and very pro surround sound reproduction. So you should be arguing against stereo reproduction too, since that's what he does. But you're not. Hmm..
 
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Graaf
Floyd's room(He is obviously not an audiophile.)

who is an audiophile? Certainly Toole is not an audiophool (copyright by John Watkinson) because he knows too much to be one

Graaf
Another thing about Dr. Toole. He is anti "stereo" reproduction, and very pro surround sound reproduction.

Toole is obviously very much pro-multichannel but is he anti-stereo? I can't find any arguments against stereo in his book. Can You?

So you should be arguing against stereo reproduction too, since that's what he does. But you're not. Hmm..

I should? Let me restate that Dr Toole is not my "guru":

I only refer to Toole in these discussions because some other people here elevated him "to some god-like status" in discussions with me here couple of years ago, apparently without actually reading the book, or at least without reading it with any understanding :rolleyes:

and they stop elevating him only after they discovered that "the body of data" he presents in the book in fact falsifies "several points" they were (and still are) "quiet adamant on" ;)

now his book is only "a body of data" ;) but they still look silly
 
So this is what Graaf wants you to know for fact. Wide dispersion speakers should be used in highly reflective, asymmetrical rooms with many reflective objects of all shapes and sizes. Other approaches(like controlling dispersion) are purely subjective and highly unscientific..
 
re: Dr Toole as a "reference" at "diyaudio multiway"

it was particularly funny to discuss in that regard with Dr Earl Geddes whose position evolved from:
I do not believe that Toole ever said that ... If you know of a statement of his that claims that I'd like to read it.
to:
As to the Toole paper and quotes, I simply don't have the time to follow this up any further. Sorry.
to:
As to "diversified opinions", Dr. Toole and I don't really have many major ones, but I do have major differences with most of the others that you mention.
to:
I hate to keep repeating myself, but I guess that I have to. Floyds comments in his book are not conclusive since the data could be interpreted different ways and he does this himself. And this is one area where I do not agree with Floyd.
to:
As I have always said, this issue is controversial.


still funny after all those years :rofl:
 
So this is what Graaf wants you to know for fact. Wide dispersion speakers should be used in highly reflective, asymmetrical rooms with many reflective objects of all shapes and sizes. Other approaches(like controlling dispersion) are purely subjective and highly unscientific..

not really :) the only thing graaf says is "try everything yourself", don't bash anything until You test it properly

unfortunately as one forum user observed years ago:

Most people will rather invest an hour to tell you it can´t work than five minutes to test it themselves.

I say - do what CLS does - he is my "hero" here - he tries everything without stupid prejudices, with an open mind
 
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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..

I agree with you. Most people do not have an optimized listening room (I have one at work, but not at home), so we will always have to keep in mind that under this "normal" conditions, real omni speakers would sound... not good. Not in terms of tonality (can actually be really good), but of stereo (or surround) reproduction. Our ear can compensate only a certain degree of unwanted reflections.

To keep the level (and number) of these reflections low, you have three possibilities:

1) modify your room. Not always possible, otherwise optimized rooms would be a majority. However, slight modifications are in most cases possibl without a divorce from your wife

2) change listening position (closer to the speakers). Similar problem as 1)

3) use speakers with a higher directivity

Point 3) is, in my view, the most practical solution. From my experience, it doesn't require ultra-high directivity, but just a decent amount. And more vertical than horizontal directivity. For example, my current speakers are a 20 cm long array of tweeters and midrange domes, with two 20 cm woofers above and below. In my living room, and my quite short listening distance (2.5 m), this setup gives a superb stereo reproduction while maintaining good tonality and "ease of listening". The tonality is not perfect, because I have to crossover too high between woofers and midrange, but I accept this at the moment. I tested these speakers in my optimized room at work, and they play there very good, too. In strongly reverberant rooms, and with a greater listening distance, the dispersion might be too high.

Baseballbat
 
...to You

Of course.

...Your ear

No, every ear. Every ear is different, for sure, and that "certain level" is different for all people, but every ear has its limit. Simple test: if you move further away from your speakers, the phantom sources will loose more and more their focus. That is because the direct field looses level vs. the reverberant field (which is, in "normal" rooms, not really reverberant, but an overlay of many reflections).

Baseballbat
 
No, every ear.

in a sense, because we can all agree that excessive "bathroom" reverberation is not good

but an early reflection is one thing and excessive reverberation is another

besides one has to take into account many qualities of a specific reflection - it's level, delay, angle, frequency content and perhaps also time structure

it is all discussed in Dr Toole's book
 
In small rooms like the usual living rooms there is no "real" reverberant field. The reverberation is dominated by reflections from various surfaces, and these reflections distort the stereo image reproduction.

Of course, it depends on all those factors you mentioned, and I wish you good luck in raytracing your room.

But there is a simple solution to this: avoid reflections. If you have absolutely no reflections, you have perfect stereo image (that image that is recorded). Sadly, it will then sound very unnatural and uncomfortable to you. So you need a few reflections, and that's what I meant: use controlled dispersion to control the amount of reflections. An omni speaker will be inferior to such speaker in the same room in terms of detail and stereo image, not necessarily tonality.

Baseballbat
 
In small rooms like the usual living rooms there is no "real" reverberant field. The reverberation is dominated by reflections from various surfaces, and these reflections distort the stereo image reproduction.

not all of those reflections affect the stereo image in the same way and also there is a controversy as to what does and what doesn't amount to "a distortion of the stereo image"

Of course, it depends on all those factors you mentioned, and I wish you good luck in raytracing your room.

it is not at all that difficult to raytrace 1st order reflections

But there is a simple solution to this: avoid reflections. If you have absolutely no reflections...

an anechoic chamber? not a simple solution then :)

...you have perfect stereo image (that image that is recorded).

perfect?

Sadly, it will then sound very unnatural and uncomfortable to you.

exactly, to be more precise - to most humans according to research done

so "avoid reflections" is a solution neither simple nor perfect :(

So you need a few reflections, and that's what I meant: use controlled dispersion to control the amount of reflections.

then we can agree that we do need "some" - right - reflections

but it is not just the amount - the level - that is important

and You seem to forget that horizontally omni is a kind of controlled dispersion too - in fact You get the same lateral 1st order reflections as in case of a front radiating high directivity box speaker which is also inevitably omnidirectional up to a certain frequency - only quality of those reflections differs - in case of an omni they are louder but they are also exact copies of the direct sound bot as regards their frequency content and time structure

now, research results dicussed in Toole's book suggest that if a reflection is not louder than the direct sound then if it sufficiently resembles the direct sound it may be less detrimental to the stereo performance of a system than a softer reflection which doesn't resemble the direct sound because of uneven off axis response of a speaker

BTW if You really have to then You can better control qualities of 1st order reflections with geometry of the stereo triangle, diffusion and deflection than with absorption which in fact only low-pass filter them, ineffectively in most cases because sufficiently broad band absorption - just of frequencies dominant in stereo perception (>500 Hz) requires really deep absorbers

An omni speaker will be inferior to such speaker in the same room in terms of detail and stereo image, not necessarily tonality.

...will sound inferior to some listeners perhaps, ok?

of course symmetry is always a requirement

I have to say that I really enjoy discussion with You, thanks! :D
 
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An omni speaker will be inferior to such speaker in the same room in terms of detail and stereo image, not necessarily tonality.

I very much beg to differ. And I believe you would too if you've had the chance to test quality omni-type speakers (or bipolars). Unfortunately not many are around. Without going into DIY for a moment, you could try and find some old top range Mirage speakers. These have fantastic stereo imagine, sound stage and detail, while having a configuration where ~70% of the output was from the rear speakers.
 
not all of those reflections affect the stereo image in the same way

Yes, but they affect it.

it is not at all that difficult to raytrace 1st order reflections

I am not talking of 1st order reflections only. You have to take higher order reflections into account, too.


Perfect in the sense that the recorded image will be perfectly reconstructed - with all drawbacks which stereo has.

and You seem to forget that horizontally omni is a kind of controlled dispersion too

me said:
From my experience, it doesn't require ultra-high directivity, but just a decent amount. And more vertical than horizontal directivity.

...will sound inferior to some listeners perhaps, ok?

No. Make a test with a an omni and a slightly directive speaker. Make sure that the latter is (nearly) CD (Yes, this is a constraint; non-CD speakers may be inferior to omnis, I was not precise in my statement). Under exactly the same conditions, the directive speaker will have the more precise stereo image and fine detail. The overall sound may not necessarily be better for you, but in these two disciplines, the directive speaker will win.

Baseballbat
 
Under exactly the same conditions, the directive speaker will have the more precise stereo image and fine detail. The overall sound may not necessarily be better for you, but in these two disciplines, the directive speaker will win.

I strongly disagree with that, and I sincerely believe you would too given the chance to test it.

Maybe it's time to make this more scientific instead of just quoting works of other, and me also vaguely referring to research I cannot disclose.

Why not make a simple decent set-up of the closest thing we can come to an omni speaker for a reasonable cost, ie. a bipolar.

With a bipolar speaker you can vary the amount of output from the rear speakers very easily by just dividing the cabinet in two parts, so the woofers are in separate cabinets as would be required. Whether it's split down the middle horizontally or vertically wouldn't matter.

When the speaker is built each pair just needs to be driven by a separate amp and now you can perform all sorts of test (which I as hinted have already done on numerous test subjects).

The beauty of this set-up is that it's basically impossible for the listener to have any knowledge on when the set-up is changed as all since all that is required is to switch to a different balance and filter setting. Prior calibration must be made to ensure that total output at the listening position is the same in all settings.
 
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