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Does sound sounds better in a room full of furniture and stuff or without ? - Page 21

post #601 of 871
Quote:
Originally Posted by amirm 
And you calling Bigus question clear? Really? You go to the doctor and tell him you have a fever, chest pain and sweats, but that he should ignore all of that and tell you what process he would use to diagnose you? You see why I choose not to answer your questions?
Glad you made this clear.
post #602 of 871
Quote:
Originally Posted by Bigus View Post

Do you honestly think someone who graduated top of the class in engineering undergrad, grad school, and Med school doesn't understand the most basic aspects a a bell curve?
After you demonstrated that, sure. You repeatedly went to the wrong place, with your last post talking about 20 million people being so situated. In all fairness, people routinely forget their schooling in this regard. Nothing shameful about it. I had to note it however since that is what you asked me: what I would do in that situation. To explain that, I had to explain what made it unusual. And how you were not appreciating the statistics and what they meant in this context.

It is surprising that you throw your degree out there but seem to have little respect or appreciation for top PhDs in this industry. Someone your degree in unrelated area trumps theirs. And the fact that they do this for a living and all you do is read forum post, with no ability to practice any of it seeing how you mic is in storage and you have sold your pre-amp.
Quote:
If you want to make things personal and believe me to be a complete idiot, just say that. Don't hide insults like this and then cry foul when you feel insulted. I don't mind the insults. I mind your higher than thou attitude about them.
You don't mind insults? Let's review a few rounds with your teacher in this area:
Quote:
Originally Posted by dragonfyr View Post

Look bigus toolus, the qualification regarding both minimum phase systems was mentioned how many times? And the relationship of modes to minimum phase as well as to modes specifically was mentioned how many times? I'm tired of ms. congeniality constantly following me around like one other lost puppy dog some may know and trying to make points that simply do not exist had someone actually bothered to read the entire post for meaning. I am tired of this. I hope he explains the remaining issues regarding the ETC and its use regarding issues involving specular reflections, for which Audyssey and similar 'room correction'(sic) devices simply cannot - despite spurious assertions of systems that can overcome fundamental limitations of physics...
Quote:
Originally Posted by Bigus View Post

You're a real class act dragon.
After being extended an unconditional apology, you devolve to schoolyard antics in response. Class.
Quote:
Originally Posted by dragonfyr 
You know, it really gets old listening to 'social tweets' that instead of adding to any understanding of acoustics now hold the 'teacher', whose only job need be to present material, responsible for not learning the material for the 'student' as well.

So tell me, after how many years of being so intimately concerned with audio and acoustics and after all the time spent on this forum (in one case assuming just 1minute per post, a modest estimate of 350 HOURS simply posting!) as well as all the time spent reading marketing brochures, how much time has actually been spent reading any actual reference text about acoustics?

Obviously not much.

Its not local's job to teach or to learn for you. He has been gracious enough to present material. Its YOUR job to expend the effort learn it. And while local is persisting in masochistically trying to present basic material to those who do little more than complain, I no longer care if you learn it or not as its rather apparent that the vast majority here lack the the desire to actually make an effort to learn (as evidenced by the ratio of posts to excuses for not having read such material) and the subsequent basic prerequisite acoustics knowledge to enter into an informed conversation as evidenced by a group not even aware of the fundamental distinction between large or small acoustical spaces!

What a genuinely pathetic mentality dominates the 'oh so interested' group of do nothing victims who can't be bothered to simply read and learn basic prerequisite facts sufficient to even engage in an informed discussion who instead offer nothing but denigration based squarely on their own ignorance as they demand "the answer".
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Originally Posted by Bigus View Post

As often as the accusation is made that some people must not actually care about learning, it could be just as fairly presumed some do not actually care about teaching.
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Originally Posted by localhost127 View Post

it's ok, dragon - i always give them the benefit of the doubt and assume such behavior is merely due to poor quality control on the LSD in their area. nothing makes me more grumpy than crummy acid.
post #603 of 871
Quote:
Originally Posted by amirm 
If you wanted me to show you the general process, then you should pick the middle of the bell curve, not the extreme shoulders.
Ah, missed this on first reading. I think this confirms that audiophilesavant's mockery is in reality all there is. I wanted to know if there was more and created an opportunity to reveal that. When the curtain went up we found two things, this being one and the other a diversionary pretense of being confused despite slipping up and noting that you understood the nature of the question and refused to answer.

Well, we have pieced together your answer. There is no process.
post #604 of 871
Quote:
Originally Posted by Bigus View Post

That sample was not representative of the general population of ordinary living rooms??
The value was in the 15% region so yes, it was not representative of the general population. It further was inconsistent with the symptoms you proceeded to overlay on it. How many times must we go over this? Should we discuss heart disease in the context of healthy 20 year olds?

Why don't you answer your own questions so that we can see how you can drive some sense into the data you put forward?
post #605 of 871
Lol, just saw your last post. Just itching for an opportunity to post that again weren't you. Thanks for putting an exclamation point on my point for me!
post #606 of 871
Quote:
Originally Posted by Bigus View Post

For modal region and speaker selection??? Yeah, that's what we have been discussing for twenty pages. rolleyes.gif
What? You asked me about modal ringing:

"The "symptoms" could be anything. I said poor speech intelligibility, ringing bass (those often go hand in hand), soundstage collapsing to one side, etc. It could be HF harshness, amorphous image, lack of soundstage depth, or whatever subjective descriptors you wish to apply. Doesn't matter. You have a room and an RT60 value. How do I proceed?"

Now it is my problem for answering it? And we got into speaker issues because your scenario forced it that way. And at any rate it is silly to think issues with regards to the sound you hear must be limited to room acoustics.

I missed the bit about poor speech and intelligibility going hand in hand with ringing bass. Please demonstrate why these go hand in hand. Explain how an overly live room but with perfect bass response cannot have speech intelligibility problems.
post #607 of 871
Quote:
Originally Posted by bigus 
That sample was not representative of the general population of ordinary living rooms??
Quote:
Originally Posted by amir 
The value was in the 15% region so yes, it was not representative of the general population.
omg. And after attempting to lecture me on gradeschool stastistics? Amir, do you know what a sample in this context is?

Quote:
It further was inconsistent with the symptoms you proceeded to overlay on it.
In the millions of rooms that might yield that measured value, none of them will have such problems even when using anointed speakers? Not that it matters, as I made it clear that if you really had that much issue with that set of possible problems, substitute another set that for whatever reason made you more comfortable. Didn't matter. But you knew that as you admitted and continued on with the diversions, and still continue as if I don't see right through them.

Quote:
Why don't you answer your own questions...
I know, hard to resist a habbit isn't it.
post #608 of 871
Quote:
Originally Posted by amirm 
Explain how an overly live room but with perfect bass response cannot have speech intelligibility problems.
Diversion #173,930. Calculate this, answer that, do this, find that, explain this...

No need to try and explain your ridiculous misreading or manipulation. Do you know what the word 'often' means?
post #609 of 871
Quote:
Originally Posted by Bigus View Post

I know, hard to resist a habbit isn't it.
You can't be serious. You are refusing to answer your own questions? This is what you said about my answer:
Quote:
Originally Posted by Bigus View Post

You said a lot of stuff but never approached the question.
You are not approaching your own questions just the same?

I hate to ask but do tell the reason why.
post #610 of 871
Quote:
Originally Posted by Bigus View Post

Diversion #173,930. Calculate this, answer that, do this, find that, explain this...
No need to try and explain your ridiculous misreading or manipulation. Do you know what the word 'often' means?
Well explain why they "often" go hand in hand.
post #611 of 871
Diversions #173,931 and #173,932. Calculate this, answer that, find this, do that, explain this...
post #612 of 871
Quote:
Originally Posted by Bigus View Post

Diversions #173,931 and #173,932. Calculate this, answer that, find this, do that, explain this...
Got it. So next time you ask me to explain anything, or prove any statement, or show any data to back what I am saying, I can just refer to this post of yours and refuse.

If you are going to use a debating tactic on someone you need to make sure it doesn't immediately refer to your own post! wink.gifsmile.gif

You gave me a better answer than I was hoping Bigus. Thank you.
post #613 of 871
Lol, you've been refusing to answer for several pages now, and being diversional is in your blood. Pointing to my post making fun of that will only provide more entertainment, so be my guest. biggrin.gif

Maybe we can take a "sample" of these excuses and make an instructional sticky on how not to behave. biggrin.gif
post #614 of 871
Quote:
Originally Posted by amirm View Post

“I also think we share the view that reasonable thickness absorbers and diffusers absolutely work and there is no requirement for 45 inch deep diffusers or 8 inch absorbers as team dragon+local propose.”

And again we are treated to the disingenuous BS resented by a person who lies about what others have suggested and rejects that which even his mentor Toole has clearly stated.

We have stated that treatment must be broadband, such that it affects the specular behavior across the board,

Here is what Toole says:
Quote:
Originally Posted by Toole View Post


“7.1.2 Obviously if the purpose of the absorbing material is to attenuate the reflection, the material should be equally effective at all frequencies. Given the duplex nature of sound fields in small rooms, it seems reasonable to expect similar performance at all frequencies above the transition region.

9.2.1 Any device inserted into a reflected sound path— reflector, absorber, or diffuser—should perform uniformly well at all frequencies above the transition frequency region, say, 200–300 Hz. This is in order to preserve the spectral balance of the loudspeakers, to uniformly attenuate the full spectrum of reflections, and to ensure that the precedence effect is maximally effective.”

“Thus from the perspectives of maintaining the excellence in sound quality of good loudspeakers, rendering an unwanted reflection inaudible, and preserving the effectiveness of the precedence effect, there are reasons not to alter the spectrum of reflected sounds. One is free to redirect them with reflectors or diffusers, or to absorb them with lossy acoustical devices, but in each case, the process should not alter the spectrum of the sound above some frequency toward the lower side of the transition region in a small room. It seems reasonable to propose, therefore, that all acoustical devices used in listening rooms— reflectors, diffusers, and absorbers—should be uniformly effective above about 200 Hz. For resistive absorbers this means thicknesses of 3 inches (76 mm) or more.”


Now, how thick does the treatment need to be?

Simple: It depends upon the specific material. And for porous material in particular, that depends upon the acoustical impedance of the material, and in particular, a factor known as gas flow resistance.

But our fiend, being totally ignorant of the process fails to realize that any suggestion we made was based specifically on the material presented, for which we provided state of the art modeling data of which Amirm neither understands nor has ever had access. And certainly nothing of which he has ever empirically measured – seeing as how his ENTIRE position is based solely on what he has read in but one book! But one is welcome to debate the accuracy of the simulations with either Dr. Ahnert or Marshal Day - each based on the latest research into the behavior of various absorption and acoustical impedance. But, but, but, but.....

And as far as his BS statement that we have presented a “requirement for 45 inch deep diffusers”, I challenge him to find one statement anywhere where ANYONE has ever made that assertion. For you see, folks, he is a consummate liar.

But, one should not forget this as they read later in the post that Toole DOES specify a minimum "8 inches" deep for diffusors and a MINIMUM "12 inches deep" for scatters such as polycylinders! Again, completely consistent with what we HAVE proposed!

But being as learned as he is, he has no idea what thickness is appropriate for ANY treatment for any reason, as he is totally ignorant of the determinant criteria that determine the low frequency cutoff in performance. He does not understand the various physical topologies of the treatments nor their design, nor the individual behavior characteristics of the various designs.

You see, all our friend can do is perform word searches and grasp for anything that appears, and the cut and paste.

And he fails to understand that when you have boundaries whose acoustical impedance is predominantly resistive and where the employed treatment is broadband, the ETC is absolutely a reliable measure, as all of the reflections possess similar spectral contents – satisfying the potential mistake that he and his friends worry about seeing as how they advocate the use of non-broadband treatment contrary to his mentor Toole.

Therefore we might want to again remind them of Toole’s position regarding room treatment:
Quote:
Originally Posted by Toole View Post


“7.1.2 Obviously if the purpose of the absorbing material is to attenuate the reflection, the material should be equally effective at all frequencies. Given the duplex nature of sound fields in small rooms, it seems reasonable to expect similar performance at all frequencies above the transition region.

9.2.1 Any device inserted into a reflected sound path— reflector, absorber, or diffuser—should perform uniformly well at all frequencies above the transition frequency region, say, 200–300 Hz. This is in order to preserve the spectral balance of the loudspeakers, to uniformly attenuate the full spectrum of reflections, and to ensure that the precedence effect is maximally effective.”

And again:
Quote:
Originally Posted by Toole View Post

“In their examination of the audibility of reflections, Olive and Toole looked at detection thresholds as high frequencies were progressively eliminated from the reflected sounds, as they might be by frequency-selective absorbers.

They found that only small to moderate threshold elevations occurred for low-pass filter cutoff frequencies down to about 500 Hz, where the investigation ended. Removing the high frequencies alone is not sufficient to prevent audible effects
[32].

Finally there are the indications that the precedence effect is maximally effective when the spectra of the direct and reflected sounds are similar [4], [18], [20]. If the spectrum of a reflection is different from that of the direct sound, the probability that it will be heard as a separate spatial event is increased—not a good thing.

Thus from the perspectives of maintaining the excellence in sound quality of good loudspeakers, rendering an unwanted reflection inaudible, and preserving the effectiveness of the precedence effect, there are reasons not to alter the spectrum of reflected sounds. One is free to redirect them with reflectors or diffusers, or to absorb them with lossy acoustical devices, but in each case, the process should not alter the spectrum of the sound above some frequency toward the lower side of the transition region in a small room. It seems reasonable to propose, therefore, that all acoustical devices used in listening rooms— reflectors, diffusers, and absorbers—should be uniformly effective above about 200 Hz. For resistive absorbers this means thicknesses of 3 inches (76 mm) or more.”



Interestingly, Toole repeats this assertion multiple times in papers and his text, but his alleged disciple simply myopically chooses whatever facet of behavior he chooses and ignores the rest.

But the Precedence and Hass effect are time domain behaviors! But don't worry folks, as we have been informed by an utterly unreliable source that the time domain is of no importance in acoustics or psycho-acoustics.

One will also note that in such an environment, where the boundaries are indeed resistive and reflective, and where the treatments are uniformly broadband, the ETC will see reflections that are spectrally equivalent to the incident signal as they are uniformly addressed by the boundaries and can indeed be compared without their spectral nature being corrupted by the improper application of non-broadband equalizing treatments.

And it speaks volumes that he persists in advocating treatment methodologies that result in the corruption of such results. But he has to be intellectually dishonest in order to perpetuate his hallucination as he has a personal vested interest in discrediting what he mistakenly feels is a flawed technology which is in fact flawed only insofar as folks like himself advocate MISTAKES in process that result in the corruption and effective equalization of the reflected signal.

But that is what you get when you listen to someone with absolutely no personal expertise and whose sole claim to fame is to have done a book report and to have attended a “several day class”. Unfortunately such does not even quality one as a decent marketeer. The result is to watch a chameleon who cuts and pastes whatever his word searches uncover without regard to consistency or fact.

So you can well see why he must resort to lies when he personally has nothing with to reason.

And one might also want to review Toole’s suggestions for room treatment. Far from simply using a few scattered pieces of furniture, you may note that his recommendation is essentially identical with the various napkin analysis proposals that have permeated the web for 20 years.

But expect amirm to further attempt to obfuscate and avoid any direct response. As he does here where you are treated to his usual erudite and asinine response:

And be sure to notice the “Blackbird Studio” logo affixed to the graphic. This is significant as this response is satisfied in a location where professionals rejected the reflection rich environment that resulted in (see below!!!) a less precise "sofer image". So let's take a survery here: How many folks desire a less precise "softer image?
So much for dictatorial polls and surveys… LOL!
Quote:
Originally Posted by amirm View Post

Quote:
Originally Posted by localhost127 View Post

"This is the graph. Note that it refers to Dr. Toole research"
i-45H4Xpv-X2.png
this graph - what domain is it in?
I am pretty sure it is the audio domain. biggrin.gif

"The AUDIO domain..."…Such a cute, if absurd, answer, isn’t it?...resulting from the fact that he would have to contradict his oft made claim! ...And one of which he is not even sure! It is also indicative that he 1.) Either does not know the correct answer, or 2.) He realizes that if he answers it correctly that he will contradict his assertion made all along that the frequency domain is sufficient and take ownership of the title of fool that he indeed demonstrated and earned long ago by failing to recognize the domain of his of the repeated graphic. So, what do you think the reason is? Admittedly it is a hard choice between the two options which are that of total ignorance and total error.

It is indeed funny… Tragic actually… As to answer the question correctly he would have to contradict his repeated assertion that the answers are to be found in the frequency domain, and that the time domain plays no pertinent role – despite his mentor stating performance specifically with regards to gain and arrival time – in the TIME domain. …With NO reference to frequency content whatsoever.

So all he offers is avoidance and obfuscation , and a near total lack of personal knowledge of acoustics.
Quite an array of talent and resources from which you can pick, isn’t it?

But hey, if you desire a reflection rich environment to make the imaging large, amorphous and imprecise but ‘large’, simply by a pair of Bose 901 direct-reflecting speakers, and you will achieve for a fraction of the cost what Amirm would like to sell to you for significantly more.

Or, if you are interested in actually following what Toole prescribes, you will want to consider ONLY speakers featuring a UNIFORM power response – which means jettisoning easily 95% of what is available in the market. And then consider treating your room in the following manner:

And note that the treatment scheme is remarkable similar to the ‘classic’ treatment schemes that have become commonplace and almost generic prescription over the past 20 or so years. And note that all said treatments must be broadband in nature:



1000

1000

1000

1000


Now compare that to amirm’s room featuring the almost exclusive use of absorption along with very bandwidth limited diffusion limited in its effectiveness to high frequencies for the treatment of flutter echo.

Note in particular his reference to the need for ALL treatments to be BROADBAND...with the notable exception of the carpet rolleyes.gif...as if the polar response of a tweeter is going to result in much use for a carpet anyway, as it is ineffectual against the low-mids and where the listeners (bags of water) will be more effective than the carpet..

And a ceiling cloud that ideally disperses the energy to the sides, or failing that is broadband absorbent, is not limited to a use for only the front row - but for all rows as appropriate!

One will also note that Toole advocates a schema that requires treatment of just about ALL of the primary room's surface.

And Toole also specifically advocated PRESSURE based LF bass corner traps as opposed to velocity based porous LF corner traps for modal control. A very productive recommendation.

Note that the treatment doesn't vary to any significant degree from what has been suggested for the past 20 years - with the exception that all treatments MUST be broadband. Conditions the treatment in HIS room do NOT satisfy.... So, I guess you should ignore what he says , as it deviates from Toole, as well as ignoring as he does....Boy, now that's news!rolleyes.gif

Ironically, aside from Toole's admonition to use NEW speakers featuring a UNIFORM POWER RESPONSE, not much is new. And as far as boundary treatments are concerned, with the exception of the admonition that carpeting be utilized, there is nothing really new at all (unless you consider the LONG TIME (40+ year) BEST PRACTICE of utilizing BROADBAND treatments 'new' - insofar as it contradicts many casual recommendations so often read on the web)... And I wonder where we heard THAT admonition prior to the book report?

And as Toole (in the last post4ed page) specifically proposes a less precise "softer image", how many folks here prefer a less precise "softer image"?

Book reports are nice, but some would do well to go back and re-read the inspiration for their anything but well presented book report again – this time for MEANING. And then one can present their dictatorial preference based on taste to those preferring a less precise "softer image" to those who desire such a response.




.
Edited by dragonfyr - 7/22/12 at 2:41pm
post #615 of 871
Quote:
Originally Posted by amirm View Post

We also both use our real names and hence what we say, reflects on our personal reputation. Hope the members note these as they read our posts. smile.gif

I certainly agree with that.

--Ethan
post #616 of 871
Quote:
Originally Posted by Ethan Winer View Post

Quote:
Originally Posted by amirm View Post

We also both use our real names and hence what we say, reflects on our personal reputation. Hope the members note these as they read our posts. smile.gif

I certainly agree with that.

--Ethan

Since you folks are actively selling stuff and taking folk's money, I would certainly HOPE that you identify yourselves.

And anyone who wants to talk privately there are no hidden identities. Otherwise ALL of the information we present can be EASILY substantiated with documentation from ACTUAL world class acousticians.

Unlike many of the OPINIONS presented as fact presented by some who complain that others are here NOT to SELL crap, but simply to explore the ACOUSTICAL principle and for whom the ACOUSTICS takes precedence...and maybe even present better options designed to enable folks and help them avoid wasting time and spending unnecessary monies.

But its always fun to watch when the names selling stuff fall flat on their faces pushing anecdotal misnomers and slang rather than passing on the benefit of real research and real science....and hence the cries of foul when they find themselves on the WRONG side of acoustical physics.

Next we will read of them blaming gravity for their logical face plants....

Maybe we should instead be complaining that vendors and those with a vested monetary interest are not required to have a "VENDOR" label attached to their ID... After all, trolling the Internet forums and posting constitutes almost the SOLE business model for the various vendors here to generate business.

And yet we hear nothing of this from those generating a profit who complain that there are folks present who are NOT here to sell crap and are not here for personal aggrandizement or profit... Oh, those terrible folks who are concerned only with the accurate presentation of acoustics...as after all, they may squirrel what might otherwise be a lucrative sale! The Bastards!!!!! rolleyes.gifrolleyes.gifrolleyes.gif



.
Edited by dragonfyr - 7/22/12 at 9:56am
post #617 of 871
Quote:
Originally Posted by dragonfyr View Post

Since you folks are actively selling stuff and taking folk's money, I would certainly HOPE that you identify yourselves.
It goes beyond that. If we say things that are proven wrong, it impacts our personal reputation. My employees and friends routinely read my posts. I therefore pay great attention to the tone and substance of what I have to say.

You on the other hand have no such worries. You can fabricate things, be insulting, etc. and get away with it. Not saying you do it all the time but you clearly practice such as evidenced by what I have quoted from you (see what you told Bigus in the other thread). Should things get really bad, you can always come back under another gamer alias. Ethan and I can't do that. Neither can Dr. Toole. Dr. Olive. Dr. Bradley. Dr. Yang. Clark. etc. We have to live up to much higher standard than you.

And transparency here does not stop at using our real names. We share what we have in our homes and businesses when it comes to audio. We share measurements. We share pictures. We share data. We share who designed what. We share what equipment is there and why. You do none of this. You hide behind a bush throwing rocks toward this information while with a straight face refuse to provide one scintilla of evidence that you own any audio equipment or enjoy any music.

None of this makes us right automatically. We still have to demonstrate that. And demonstrate we do. I quote a ton of research. Independent data from multiple sources. What do you do? File a protest left and right that folks should not quote research. What an absurd concept! Then you turn around and cut and paste a bunch of stuff like you did in your last post. What is good for you apparently is completely unsuitable by others.
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And anyone who wants to talk privately there are no hidden identities.
Why is it not there publicly? Even anonymously why have you not ever shared a picture of your room so that we can see how deep your carpet is to clean up your ETC reflection there? And measurements so that we are enlightened on how well things can be done? You refuse to even acknowledge these points. This is not a sign of a person who confidently stands behind his work. If what you state is the acoustic truth, then you should be proud to put your name next to it.
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Otherwise ALL of the information we present can be EASILY substantiated with documentation from ACTUAL world class acousticians.
Why not say the sun comes out the west again and expect us to take it at face value? Why are the few of you so big on such generalizations? Major luminaries in the business who disagree with you don't count but there are "ACTUAL" acoustical who remain nameless who sanction what you do here? I have repeatedly used the same experts you use to show you that your position is not consistent with them.

In the other thread we had this interchange:
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Originally Posted by amirm View Post

Quote:
Originally Posted by dragonfyr View Post

A far as "any listening or test data involving single reflections", if I simply count those performed at the various SynAudCon functions, those alone would amount to more than you have even read about. And if you want to "see" the results of many of them, go read Sound System Engineering, or Everest's Master Handbook, as Don published many of them and Everest sourced almost ALL of his measurements from SynAudCon functions!
...You talk about reading the book, Sound System Engineering. In chapter 6 (Audio and AcousticMeasurements), before he talks about measurement techniques including ETC, Don Davis has this to say:

"The finest acoustical measurement apparatus available cannot duplicate what a trained human listener can achieve. If we examine an unknown signal with all extant equipment we can’t tell if its music, noise, speech, or gibberish, but a $2 loudspeaker allows the trained human listener to tell which, and if speech, what language."

You believe this? Why do you think he is making this preface on a chapter focused on measurements?
You had no answer of course. Because you don't want to listen to your own experts when they tell you it matters what your ears say and what your instruments are blind to. I can't think of a more major failing in audio than ignoring what we hear vs what we can measure.
Quote:
Unlike many of the OPINIONS presented as fact presented by some who complain that others who are here NOT to SELL crap, but simply to explore the ACOUSTICAL principle and for whom the ACOUSTICS takes precedence...and maybe even present better options designed to enable folks and help them avoid wasting time and spending unnecessary monies.
Let's compare notes. Dr. Toole says you can leave side walls bare without any treatment. You say run ETC and should you see a reflection you should do what with it? Ignore it? If so, then why should I run ETC? I assume I should run it because you then want to school me on how deep of an absorber or diffuser I am supposed to put there. If so, then you are the one costing us money. Fact that you don't sell it is not material. You misinform users and cost them in their pocketbook. Why? Because you ignore the science of how we hear. You are a slave to a measurement and can't see past its limitations and lack of correlation to human perception. Cotton is stuffed in one's hear and kept pushed further in the more data that is presented to say you are wrong. And when faced with the mountain of data, you get personal.
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But its always fun to watch when the names selling stuff fall flat on their faces pushing anecdotal misnomers and slang rather than passing on the benefit of real research and resl science....and hence the cries of foul when they find themselves on the WRONG side of acoustical physics.
Real science? You mean other than 500 page book that Dr. Toole has written or countless AES and ASA papers? You do want to exclude that library of data, don't you? Otherwise, I can quote all that research again that directly contradicts your point of view.
Quote:
Maybe we should instead be complaining that vendors and those with a vested monetary interest are not required to have a "VENDOR" label attached to their ID... After all, trolling the Internet forums and posting constitutes almost the SOLE business model for the various vendors here to generate business. And yet we hear nothing of this from those generating a profit who complain that there are folks present who are NOT here to sell crap are not here for personal aggrandizement or profit....
Let's test this theory. If Dr. D'Antonio who runs the world’s most famous if not the largest acoustic treatment company who routinely sells products that according to you are not good enough came here, you would say all of this to him? Go head. Let's see the answer to that.
post #618 of 871
So we are now witnessing the real names vs. pseudonyms diversionary discussion so he can continue to avoid answering Bigus's question.

He has already told me he has no intention of answering my question. Why doesn't he man up and admit he has no intention of answering Bigus's question either instead of continuing with this charade.
post #619 of 871
Don't let the "no intention" aspect divert you either. He has NO ABILITY to answer in an informed manner reflecting any actual knowledge of acoustics other than what he can find via word searches and cut and paste.
Quote:
Originally Posted by amirm View Post

Let's test this theory. If Dr. D'Antonio who runs the world’s most famous if not the largest acoustic treatment company who routinely sells products that according to you are not good enough came here, you would say all of this to him? Go head. Let's see the answer to that.


Such pathos, such angst, such BS.

Is this the guy who claims that I and local have stated that diffusors MUST be AT LEAST 45 inches deep??????rolleyes.gifrolleyes.gifrolleyes.gif

Sure, I could say it, but it would not apply at all to him, seeing how he is neither a troll nor someone pushing purely derivative products - but rather one actually doing original research and design.He also acknowledges the role of one's subjective preference in selecting a response model.

And please, continue to lie and misrepresent what we have said in your quest to demonstrate your integrity! And please, show us a picture of an "ETC meter"! I would LOVE to see one!rolleyes.gifwink.gifrolleyes.gif You know, the "meter" which is frequency blind, despite the impulse, ETC and other responses most commonly being derived from a swept frequency sweep stimulus and from the resultant frequency response that is also a transfer function of the space...Sorry, but it ain't the "meter" that is blind... Its the operator!

And then we have our Luddite friend return with the bogus ears versus measurements debate, ignorant of the nexus between Don Davis and Dick Heyser and ignorant of what either of them taught. But then, eyes are magnificent instruments too, but I guess he would invalidate the use of microscopes, telescopes and various forms of lighting, etc., as well. The more he talks, the more he demonstrates why no one should be listening.

And yes, the litany of persons who actively participated in SAC, just to start the list, are all unknown and-insignificant. Funny, hos word search and cut and paste skills seem to fail him in listing some of them...

And I have no interest in dancing and explaining acoustics for someone who claims to be an authority on the basis of reading a book and spending a grand "several days" hearing about the contents of a book and for which I have no personal respect..

I have personally been in quite a few workshops and seminars with Dr. D'Antonio, and suffice it to say that many have given him a humorous ribbing for the marketing of his products. But NO ONE has challenged the science behind them! And fortunately people are not misrepresenting Dr. D'Antonio's work as you have done with Toole's.

StudioDesWkshp87....pdf 158k .pdf file

But also suffice it to say that D'Antonio's application of objective science is world class. And there is another critical fundamental difference between you and he aside from knowledge - we respect Dr. D'Antonio.

I know Dr. D'Antonio, and YOU are NO D'Antonio.

And I know of no issue about which that I have any substantially divergent views from Dr. D'Antonio. And that includes Blackbird, designed primarily for the surround environment, which I have been in and which does sound good. Butt prefer a more defined precise sense of localization and imaging provided by alternative designs, balanced in part by alternatives being achievable in a more practical manner. - as absolutely amazing as those diffusors are... Plus, I am not as enamored with surround as is Toole. You see, I DO acknowledge the role of subjective preference to which you only make reference as you then proceed to dictate preferences while denying each individual the right to differ in your totalitarian forced march.

And no one on this forum is anywhere near the level of Dr. D'Antonio. And folks such as yourself have absolutely no formal training in acoustics.

Get a clue, clueless.



.
Edited by dragonfyr - 7/22/12 at 6:01pm
post #620 of 871
Quote:
Originally Posted by dragonfyr View Post

Sure, I could say it, but it would not apply at all to him, seeing how he is neither a troll nor someone pushing purely derivative products - but rather one actually doing original research and design.He also acknowledges the role of one's subjective preference in selecting a response model.
Pushing purely derivative product? So if someone is selling products that are not derivatives, they have no sales motive? That's some standard! He does indeed acknowledge *and* recommend the work of Dr. Toole and his research. What is your excuse for calling him an idiot instead saying he doesn't know what ETC is or how to use it? You think Dr. D'Antonio would say that about Dr. Toole?
Quote:
And please, show us a picture of an "ETC meter"! I would LOVE to see one!rolleyes.gifwink.gifrolleyes.gif
Putting aside that I used that term jokingly, you honestly are unfamiliar with such terminology? If I use my $25,000 Audio Precision analyzer in its analog mode, all it does is automate the use of a RMS/Peak meter. Let's say I want to measure frequency response. The tone generator starts at a low frequency and keeps stepping up. At each step, the tone is fed to the device under test and then a peak or RMS *meter* reads the resulting output. That data is captured and then plotted. If you connect all the dots, you have a graph. But the graph is nothing but a sequence of meter readings. Indeed, that is the terminology used in AP's manual and user interface. Your comments in this regard is as if you are not aware that there is an engine in a car and demanding that I show you that!

In the simplest form, i can measure the impulse response using the same analog meter. Yes, the modern way to measure IR and ETC is using a swept sine where the frequency is exponentially increased and inverse FFT gives us the impulse response. But the core concept of a meter should not be foreign to you.

This is on top of you not having any sensibility about the joking way I used that term.
Quote:
You know, the "meter" which is frequency blind, despite the impulse, ETC and other responses most commonly being derived from a swept frequency sweep stimulus and from the resultant frequency response that is also a transfer function of the space...Sorry, but it ain't the "meter" that is blind... Its the operator!
You are confusing measurement technique with the resulting output. If I add X+Y and get 2, can you tell me what X and Y are? Of course you cannot. Yes, programs like REW that use swept sine can at any time show you the frequency response measurements since they use the same technique for both time and frequency domain. This however does not in any way change the fact that ETC output from the program is frequency blind. There is no information in the ETC that tells you the the spectrum that contributed to each reflection. And even if there were, you could not compare them because you cannot in your head equalize the difference between how carpet filters sound and a diffuser. You are dabbling in signal processing alchemy by pretending otherwise. And it is not like I am the only one who is telling you this. I quoted Dr. Toole telling you this.
Quote:
And I have no interest in dancing and explaining acoustics for someone who claims to be an authority on the basis of reading a book and spending a grand "several days" hearing about the contents of a book and for which I have no personal respect..
I have decades of experience in signal processing. It was not a hobby. It was not forum reading. It was not a few workshop. It was not a book. It was my job to know audio and video processing. I know topics like we are discussing above first hand. There is a reason after every tactic you tried, you had no choice to concede that ETC is useless in a furnished room, or one with varying acoustic material. How could anyone with no knowledge pin the mighty Dragon to he ground this way? smile.gif
Quote:
I have personally been in quite a few workshops and seminars with Dr. D'Antonio and suffice it to say that many have given him a humorous ribbing for the marketing of his products. But NO ONE has challenged the science behind them!
I have not done that either. You seem to be the one deciding which expert you were going to put down and which one not. We do have Bigus however thinking that both Dr. D'Antonio and Toole are wrong with respect to what constitutes a broadband diffuser:
Quote:
Originally Posted by amirm View Post

Quote:
Originally Posted by Bigus View Post

Yup. Sorry, Toole's words taken into consideration, 500Hz is still limited in bandwidth.
Limited in bandwidth? Let me quote Dr. Toole for you on the product spec I showed you:

'Figure 21.12 [graph from Dr. D'Antonio] shows a comparison of a standard version of a Schroeder diffuser with an RPG Modffusor in two configurations. These designs get better as they get larger. At 7.9 in. (0.3 m) deep and exhibiting useful diffusion down to about 300 Hz, they appear to meet the requirements for wideband diffusers and, interestingly, are very close to Gilford’s 1/7-wavelength estimate for depth requirements (Gilford, 1959)."

And in how to provide general absorption in the room:

"If RPG Modffusors (exposed absorption coeffi cient = 0.2, fabric covered it is 0.6) were used along the side and rear walls, and they would contribute about 128 × 0.2 = 26 sabins, but if they were covered with fabric for appearance, that would increase to 77 sabins."

Seems like you are finding yourself on the other side of Dr. Toole's recommendations again...
Quote:
And where is the rest of my quote? wink.gif I didn't say it isn't without some use, but I don't consider it broadband, nor reaching nearly the full potential diffusion can offer.
No, you said this and I quote: 'And 6-8" well depth is hardly adequate to make a broadband device. These things need to be big - just the way it is. High frequency diffusion and scattering may offer some benefit, but if you really want the achieve a signifant fraction of the potential benefits you have to pony up the space. "

"Hardly adequate" and "significant fraction" describe the performance of an 8 inch diffuser that goes down to 500 Hz flat and still retains a third of its alpha by 300 Hz?

Why don't you say who is right. Bigus, or Dr. Toole & Dr. D'Antonio?
post #621 of 871
Quote:
Originally Posted by amirm 
If we say things that are proven wrong, it impacts our personal reputation.
It certainly does.

Quote:
I therefore pay great attention to the tone and substance of what I have to say.
Unless you are intentionally trying to appear arrogant, condescending, and ignorant, pay greater intention.

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We have to live up to much higher standard than you.
I see no evidence of that. On the contrary, as I've highlighted numerous times you seem to hold everyone else to a higher standard than yourself.

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I quote a ton of research.
And demonstrate that the ability to quote ≠ the ability to understand.

Quote:
Dr. Toole says you can leave side walls bare without any treatment. You say run ETC and should you see a reflection you should do what with it? Ignore it? If so, then why should I run ETC?
You room consists of speakers, a floor and side walls? Interesting house. I'd love to visit sometime.
post #622 of 871
I think the joke has about run his course. It has been an entertaining ride. smile.gif

Run a series of full bandwidth and band limited ETC's in a room, any room, treated or furnished or otherwise. From the ETC data you can determine the exact source of every potentially significant reflection. By comparing the specific energy return for each reflection to the direct signal in each frequency band, you can determine the filtering effect each and every reflection or diffraction point has on the incident energy (if you know or measure the polar response of the speaker you know this exactly, otherwise you know this in relative terms which in the end is what matters... reflections vs direct spectrum). You then know (a) the gain of the reflection in known frequency bands, thus (b) which reflections are spectrally similar to the direct signal, and (c) if not, in what way they differ, as well as (d) the timing of the reflection vs the direct signal. Armed with this data, and in combination with an understanding of how we perceive sound from various directions and timings, one may begin the task of identifying problems and developing solutions.

If the reflection from a wall has a significant spectral mismatch vs direct signal, there could be an issue with the speaker, wall, or both. You may or may not wish to exchange the speaker for many other various reasons. If not, you can modify the boundary to restore spectral balance. And yes, if required, one can construct a targeted absorber that corrects the imbalance, and verify success with ETC. Or suppress the reflection enough that the imbalance doesn't matter, again verifiable with ETC. That may be the case if less amorphous widening of the soundstage isn't desired, and/or especially in the case of a dedicated multichannel environment. Or if possible and you have the latitude, redirect the energy elsewhere to be returned to the user later in a more diffuse manner. Again, ETC can help map this path and veriphy the desired effect.

Or you might find that some stiff drapes covering most of one sidewall with loose liners hanging behind have created an effective membrane absorber over a narrow bandwidth, say around 500hz, yielding a room which seems to be on the low end of rt60 in that narrow range but have quite lively reflections above and below. By identifying the problem, you can decide how to approach it. Perhaps change the drape material or swap to blinds, or alternatively broaden the effective bandwidth of absorption and use multichannel processing. In any case, you would also see the obvious mismatch with the opposing bare wall and could apply treatments there to match the behavior of whatever solution you pursued, all verified with ETC. Not all problems are sidewall or general liveliness issues. You may find an annoying reflection/diffraction coming from your center under a big flat panel, mains flanking an entertainment console, it a lamp sitting up front off to the side. Such reflections coming from up front can be especially degrading to the sound. By identifying the source, you can try various modifications in positioning of the involved equipment, or modification of their surfaces, or both, and verify the problem is resolved with ETC.

The problems can be quite varied, often unexpected (a far cry from just looking around the room and knowing what they are), and all identified with ETC. You gather data, use acquired knowledge of how humans perceive sound based on timing, gain, and spectrum, compare notes with your desired goal for the room (two channel or multichannel, precise or spacious, dedicated or multiuse) and then make informed decisions about what changes need to be made to which boundaries and edges to achieve that.

If you are starting with a bare room, your task is much easier and you might be served well with full bandwidth measurements only.

Any claims that ETC is so limited that it can't deal with whatever conditions you may find in your room come from an uneducated and dogmatic understanding of the basic concepts and a misreading of the relevant research.
post #623 of 871
Quote:
Originally Posted by Bigus View Post

Run a series of full bandwidth and band limited ETC's in a room, any room, treated or furnished or otherwise.
A series? Please walk us through how you run band limited ETC. What would those limits be and why?
Quote:
From the ETC data you can determine the exact source of every potentially significant reflection.
What makes them significant? Because they matter to a human or a dumb meter?

Why would you need a meter to tell you there is a reflection? You can't think of any other way to determine that?
Quote:
By comparing the specific energy return for each reflection to the direct signal in each frequency band, you can determine the filtering effect each and every reflection or diffraction point has on the incident energy (if you know or measure the polar response of the speaker you know this exactly, otherwise you know this in relative terms which in the end is what matters...
In each frequency band? What frequency band? Please show an example.

You say you know the relative terms. Please tell us how you determine the relative energy from the carpet and curtain you mentioned in your hypothetical room.
Quote:
You then know (a) the gain of the reflection in known frequency bands, thus (b) which reflections are spectrally similar to the direct signal, and (c) if not, in what way they differ, as well as (d) the timing of the reflection vs the direct signal. Armed with this data, and in combination with an understanding of how we perceive sound from various directions and timings, one may begin the task of identifying problems and developing solutions.
(a) again, what frequency bands? How did you determine them? Where is an example of one you have run?
(b) how do you know which reflections are similar to the direct signal? You have measurements of such signals you can share with us?
(c) Tell us how they can differ and what you are going to do then.
(d) Sure.

Did you just wave your hand on the most important part? What to do next? I quoted you in the OC 703 thread saying you were confused and did not know how to go down this journey. How did you all of a sudden not only discover he path but became a master at it as to teach us here?
Quote:
If the reflection from a wall has a significant spectral mismatch vs direct signal, there could be an issue with the speaker, wall, or both.
The wall? What could be wrong with the wall? How do you disambiguate the three?

What constitutes significant spectral mismatch anyway? Here is a sample speaker measurement:

attachment.php?attachmentid=3584&stc=1&d=1336606200

Tell us if the off-axis response as displayed there is a mismatch or not.
Quote:
You may or may not wish to exchange the speaker for many other various reasons. If not, you can modify the boundary to restore spectral balance.
Really? How do you solve the variable directivity? Take a look at speaker B:

Toole-loudspeakers-and-rooms-p394.JPG

Please explain how you compensate for the dip between 3 Khz and 5 Khz where the off-axis response power drops off. What acoustic product compensates for that?
Quote:
And yes, if required, one can construct a targeted absorber that corrects the imbalance, and verify success with ETC.
Walk us through how "one" would design something to cure the situation above.
Quote:
Or suppress the reflection enough that the imbalance doesn't matter, again verifiable with ETC.
Hah? How do you suppress all the reflections? Build the padded cell that AJ used to talk about? What about your carpet? How did you completely absorb the reflections from that?
Quote:
That may be the case if less amorphous widening of the soundstage isn't desired, and/or especially in the case of a dedicated multichannel environment. Or if possible and you have the latitude, redirect the energy elsewhere to be returned to the user later in a more diffuse manner. Again, ETC can help map this path and veriphy the desired effect.
Failing that, it can substitute as the GPS for your car I am sure. biggrin.gif
Quote:
Or you might find that some stiff drapes covering most of one sidewall with loose liners hanging behind have created an effective membrane absorber over a narrow bandwidth, say around 500hz, yielding a room which seems to be on the low end of rt60 in that narrow range but have quite lively reflections above and below. By identifying the problem, you can decide how to approach it.
Now you are using RT60? I thought you said it was wrong to do so?
Quote:
Perhaps change the drape material or swap to blinds, or alternatively broaden the effective bandwidth of absorption and use multichannel processing. In any case, you would also see the obvious mismatch with the opposing bare wall and could apply treatments there to match the behavior of whatever solution you pursued, all verified with ETC. Not all problems are sidewall or general liveliness issues. You may find an annoying reflection/diffraction coming from your center under a big flat panel, mains flanking an entertainment console, it a lamp sitting up front off to the side.
Annoying to whom? The meter or the person? And what would you do if it is your flat panel? Cover it with an inch absorber? biggrin.gif
Quote:
Such reflections coming from up front can be especially degrading to the sound. By identifying the source, you can try various modifications in positioning of the involved equipment, or modification of their surfaces, or both, and verify the problem is resolved with ETC.
By identifying the source? Isn't the source the speaker? If one does not have your dipoles, tell us again how you managed to get strong reflections onto your front wall. And why you need a tool to know that if you have that answer.
Quote:
The problems can be quite varied, often unexpected (a far cry from just looking around the room and knowing what they are), and all identified with ETC.
The *problem* is identified with ETC? Last I checked the ETC told you there was a reflection and its supposed gain. In what way does that equate to a "problem?" Isn't that determined relative to how we hear? And if so, what do we need ETC for?
Quote:
You gather data, use acquired knowledge of how humans perceive sound based on timing, gain, and spectrum, compare notes with your desired goal for the room (two channel or multichannel, precise or spacious, dedicated or multiuse) and then make informed decisions about what changes need to be made to which boundaries and edges to achieve that.
OK. Here is the data: ETC is showing three spikes: one at -4 dB, one at -6 dB and one at -2 dB. These correspond to three closest surfaces to it. Please tell us what you do with these numbers. Please tell us what your "goals" are for your room and how you determined that. How do you know your decisions are informed? Informed based on what? What Dragon tells you or what Dr. Toole tells you?
Quote:
If you are starting with a bare room, your task is much easier and you might be served well with full bandwidth measurements only.
You think such a room has no carpet? A video projection screen? Seats?
Quote:
Any claims that ETC is so limited that it can't deal with whatever conditions you may find in your room come from an uneducated and dogmatic understanding of the basic concepts and a misreading of the relevant research.
Let's see where we are. You have gone from not knowing what to do with ETC just a few months ago and being so bad at it that Dragon and Local calling you every name in the book, to the card carrying member of the club here. Here are your posts from just a few months ago again:
Quote:
Originally Posted by Bigus View Post

ETC can certainly identify where specular reflections of sufficient gain are occurring. That is without doubt valuable information to have. But despite many suggestions to the contrary, ETC doesn't tell you what to do with those locations. It can confirm that your treatment did what you wanted it to in that location, but the bigger problem remains that knowing what you want to do isn't well defined. Test, yes, my comment goes beyond the usefullness of ETC as a tool. I don't question that (and there are many valuable tools one can use). I've raised this concern/question before and it never receives much attention. Likely, as I'm becoming more convinced, because there just isn't a really good answer.
What other valuable tools are there Bigus? I see none mentioned above other than RT60.
Quote:
Originally Posted by Bigus View Post

So maybe you just want to find an example of someone using ETC to locate problem spots in a way optimized for multichannel surround, an emulate the approach taken. Well, I'm still looking.
If you are still looking, how is it that you told us the whole story just now?
Quote:
But Everything I have found is people in studio environments working with two channels, or people in ht environments using rew in the frequency domain and/or treating their room as if it only had two channels.
Quote:
Originally Posted by Bigus View Post

An add on question, one that has been posed by myself and others in the past months, is if we identify ETC as the correct tool what is the correct goal?
Seems like lacking such correct goal, you charged ahead anyway. Wonder if that has something to do with you not having a measurement mic or pre-amp during this period and just imagining that it would all work this way....
post #624 of 871
Amir, you offer nothing of value to contribute to this topic.
post #625 of 871
Quote:
Originally Posted by amirm View Post

If we say things that are proven wrong, it impacts our personal reputation. My employees and friends routinely read my posts. I therefore pay great attention to the tone and substance of what I have to say.
Really? rolleyes.gif

Q: Don't you know anything about human auditory threshold?
Quote:
Originally Posted by amirm View Post


I guess not. Please explain it to me.
Quote:
Originally Posted by amirm View Post


I am dead serious. You saw no emoticon in my post.


Quote:
Originally Posted by amirm View Post

I didn't tell you it takes more money to create a more audible improvement. I said "audio performance."
Quote:
Originally Posted by amirm View Post

Here is a way to experiment with this idea. Does your AVR have a button to turn off the video circuits and front panel display? If so, hook up a CD/DVD player using S/PDIF coax cable. Play something quiet with lots of ambiance. Now turn up the volume good and loud (or else use headphones). Play it with the video and front panel circuits on (on both the source and AVR) and then turn them all off. Do you hear a difference? If you do, then the above factor is in play.
post #626 of 871
Quote:
Originally Posted by Bigus View Post

Amir, you offer nothing of value to contribute to this topic.

A case study in flawed critical thinking and how history repeats itself? ;-)
post #627 of 871
Quote:
Originally Posted by amirm 
I have said and I will repeat again: ETC can have uses in the hands of someone skilled who knows how it can misfire.

^
Quote:
Originally Posted by amirm 
AVS community members who are interested in enhancing the sound in their rooms have no reason to use it. Experienced or otherwise

^ a walking contradiction.

you guys remember it was only a couple pages back where amirm learned (read: was told) what the x-axis on the ETC represents, yes? and to think he has attempted to discuss the tool with authority for all this time...such funadmental errors! but it's obvious his lack of experience once he sttops copy-pasting and starts typing in his own words. "ETC meter" - lol!

this guy is a salesman; he is not concerned with addressing a particular user's acoustical problem based on their personal design requirements - he has an entire "package" to sell you and loose guidelines a la toole. he knows what he's talking about; are you not impressed by the auralex t'fusors in his room?? lol.

remember when he tried to insist the frequency-domain was responsible for the psycho-acoustics of localization and imaging? notice how he still cannot present a frequency-response measurement that has good imaging vs poor imaging? he makes claims and then when pressed does not address; merely attempts to distract. is he able to tell me what information re: localization and imaging i can determine from the frequency-response?

i'd love to learn how to identify sources of edge-diffraction via the frequency response as well. this should be interesting...
Edited by localhost127 - 7/23/12 at 6:31am
post #628 of 871
Quote:
Originally Posted by amirm 
Hah? How do you suppress all the reflections? Build the padded cell that AJ used to talk about?

by padded cell do you mean the Harman listening room??
post #629 of 871
It is tempting to once again address his many failed attempts to poke holes in my answers, but it is clear he has no intention of answering directly in return. We've been through this circle many times in this thread already. We ask a question, he asks a dozen as a response, one of which is for us to answer our own question. Talk about debating tactics. Once again I obliged him and as usual he tries to find fault in my answer. Of course he fails. The points he makes are laughable, and I may get around to addressing them, but at the moment I'm still realing on the floor from his statistics debacle and fear I might say something especially rude! biggrin.gif
Edited by Bigus - 7/23/12 at 7:33am
post #630 of 871
Quote:
Originally Posted by localhost127 View Post

by padded cell do you mean the Harman listening room??
Ha? Were you not able to follow the technical conversation? Bigus claimed that to fix the poor speaker off-axis response, he would attempt to absorb them all. Harman designs their speakers to not have this problem since their research shows it is important to make sure that the off-axis response follows the on-axis smoothly. If you get this right, then the combined sound of direct+indirect as measured in the anechoic chamber will then be a very close model of what it would do in a real room with reflections. As such, there is no need to create the so called padded cell where absorbers are put all over the place.

The money spent on such treatments should instead go toward buying a speaker that is not broken. So no, you would not see that in Harman's room. Where you would see it is in the domain you ask people to copy: Pro recording spaces where their ears have become sensitized to reflections, or prompted by misunderstanding of the audibility of comb filter, causing them to attempt to absorb all early reflections.

From Dr. Olive's AES paper on the design of that room:

"The placement of the acoustical panels in the reference listening room shown in Figs. 4 (a) and (b) is based on the scientific rationale proposed by Toole [1]. In order to encourage spaciousness (broadening of the apparent source width) the sidewalls are left untreated at the point where the first lateral reflections produced by the front channels arrive at the listening location."

Do you have an aversion to reading research papers? This answer could not have been in more plain view. Why make a statement that can be invalidated so easily?

Not related to your point but completing the strategy here is this statement:

"Most of the absorptive panels are placed along the front and rear walls at locations where the room reflections arriving at the listener will have little spatial benefit."

See, it is pretty simple what you need to do. Absorb reflections where no benefit can be shown and leave them be where there can. No measurement is necessary or useful other than to determine how live or dead the room is. If Dr. Olive can state it so simply, in plain English, why would anyone try to follow the convoluted message Bigus post? I challenge anyone to tell me that they can read what he said and know what to do next. Now read the two simple paragraphs above. I am confident that it is dead easy advice for anyone to follow.

The only reason to do otherwise is to trust your meter more than research into science of acoustics and how we hear. Please don't be slave to such things. The research here is abundant, clear and most of all, in our favor in how it simplifies our life. The few people like Local are fighting this because they don't want to lose face having proposed other schemes they had read about, incorrectly copying what pros do by hanging around their forums. Please don't put aside your sensibilities and ignore authoritative research and documentation like above and instead trust a few masked posters who have as yet, in a 600 post thread, post one measurement of their own, one picture of them practicing any of this, and continue to show as we just did in this post, that they simply are unaware of research in this area that anyone in the business would know about. You don't buy a speaker from a guy in white van in the parking lot. Or get your disease diagnosed by forum posts. Don't do it when it comes to acoustic advice either. Read Dr. Toole's book and see the incredible insight he brings to this field through his own work and that of others. You are welcome to form your own opinion distinct from his. But do so with full knowledge as to not ask the type of question Local just did.
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