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any suggestions for cables? - Page 24

post #691 of 873
Here is a post from a discussion I just read over at the Audiogon forums:

"Personally, I often wonder why we spend big $$$ on components - CDP, amp, preamp, speakers, etc., and we never recognize that the improvement in listening experience we find is directly related to the high quality of the circuitry and signal path of those components. Yet, after spending major bucks on those components, we naively connect one to the other with crap interconnects, speaker cables and power cables.

Think about it . . . I buy a $2500 CD player for the way it reproduces the source signal. I connect it to down-the-line components for which I've probably spent way more bucks, for the way they conduct the signal. But I spend $100 bucks to get the signal from one outstanding piece of gear to the other, and then wonder why I'm not getting what I want.

I'm a firm believer that connectivity is the secret to the truly exceptional sounding setup. Put a $X,000.00 signal through a $100 dollar interconnect or speaker cable and all you have is $100 dollar sound.

Don't short-change the value of high quality interconnects and speaker cables, and the value that they actually bring to the joy we share"



This guy sounds serious. When is this nonsense going to stop?
Personally I own a Bryston integrated B100SST (w/DAC) but I bought solely for resale value and build quality. I do realize it's 3x as much money ($2500) than I needed to spend on electronics. I would never, ever spend any significant amount of money on cables or power conditioners.
post #692 of 873
Quote:
Originally Posted by terry j View Post

And most here would agree with you.

Why? Because (in this context) it is in alignment with our stance.

So the corollary is we would entertain a scientifically sound dbt that found a contrary result??

Of course. This isn't a debate of 'belief A' vs 'belief B' as many seem to want to make it. Its 'belief' vs 'knowledge'.

As soon as there is scientific evidence for a 'belief' it ceases to be a belief and becomes knowledge. Anyone that would disregard the findings because they disagree with them isn't taking a scientific approach at all. That doesn't mean you accept all 'tests' though, they need to have sound methodology and statistical significance to mean anything.
post #693 of 873
Quote:
Originally Posted by terry j View Post

Have you data that 'disproves' the findings of harmon on this question? You know, that they found (in dbts...see above how important that is) that at the very least acoustic treatments are not the panacea that is commonly portrayed?

Indeed, have you *any* dbts that actually back up your claims of the effectiveness of room treatment as claimed in your post??? SURELY there would be many such dbts on the websites of the acoustic manufacturers? Just note your descriptors..terrifically better sq etc etc etc.

All he has said is that the currently available dbts that have been done on room treatments do not back up your claim blindly. But to you that is somehow proof of creating strawmen and not replying to points you did not make. Have you the dbts that show otherwise on the question of room treatment? Any?

In other words, that would be YOU responding to points he made. If you do not, then who is the kettle?

The difference is I can take measurements of the effects of acoustically treating a room and cross reference previous research into what is and is not audible. I don't need a DBT to indicate that removing a 15db null from a room with bass traps is audible, I can measure the effect and stand on the research regarding the audibility of that effect.

I can't do that with cables. In many cases I can't even get a measured acoustical difference. So to conclude that they 'make a difference' requires some unknown effect in play. The only way to figure out if that effect exists, and is worth trying to quantify, is a DBT.
post #694 of 873
Quote:
Originally Posted by xianthax View Post

The difference is I can take measurements of the effects of acoustically treating a room and cross reference previous research into what is and is not audible. I don't need a DBT to indicate that removing a 15db null from a room with bass traps is audible, I can measure the effect and stand on the research regarding the audibility of that effect.
No one cares if the difference is "audible." We care if the difference is an improvement or not. Why is this point so hard to get across? It cost money, effort, and permission from significant other often to add acoustic material to a room. Why do we take it on faith that pleasing a graph is sufficient reasoning to do that?
Quote:
I can't do that with cables. In many cases I can't even get a measured acoustical difference. So to conclude that they 'make a difference' requires some unknown effect in play. The only way to figure out if that effect exists, and is worth trying to quantify, is a DBT.
Here is a measurement I performed of different interconnects:

i-fPbXgsF-XL.png

You would look at that difference and using knowledge of how we hear, say that the drop off in the ultrasonics is not audible. How come knowledge of how we hear is not applied just the same in acoustics? Is that it is more complicated to understand than the limitation of high frequency audibility? Or is it, that as I suspect, we are as stubborn as the next guy and won't change our views in the face of science and listening tests?
post #695 of 873
Quote:
Originally Posted by amirm View Post

No one cares if the difference is "audible." We care if the difference is an improvement or not. Why is this point so hard to get across?

What? That's hard to get across because it's claptrap. If it's not audible, then by definition you can't hear it, so it simply cannot be an improvement, QED.

The first step is determining whether there's a difference at all, which is best done with measuring equipment and a rigorous test procedure. If a difference can be identified, then we can proceed to see whether people can hear it, and if so whether or not they like it.

The picture you post does show differences, albeit small while within the commonly accepted range of human hearing. That is worth taking to the next step of determining via ABX double blind testing whether or not humans can consistently differentiate two of the interconnects from each other. If so, we can begin talking about what sounds 'better'. All that being said, the interconnect with the flattest curve certainly looks to be the most likely candidate for true reproduction of sound.

Have you got a similar graph for different speaker cables?
post #696 of 873
Quote:
Originally Posted by amirm View Post

No one cares if the difference is "audible." We care if the difference is an improvement or not. Why is this point so hard to get across? It cost money, effort, and permission from significant other often to add acoustic material to a room. Why do we take it on faith that pleasing a graph is sufficient reasoning to do that?

What? So, audibility doesn't matter, and you shouldn't do it to 'please a graph'.

So, how do you define 'improvement'?

If its not audibility, and its not 'graph improvement', what is it?

If its making you feel better, by all means go for it. But don't do it then claim its an acoustical improvement, certainly don't use acoustical improvement as a sales pitch, that is the basis of everything the science folks are arguing in this thread.
Quote:
Originally Posted by amirm View Post

Here is a measurement I performed of different interconnects:

i-fPbXgsF-XL.png

You would look at that difference and using knowledge of how we hear, say that the drop off in the ultrasonics is not audible.

Yup
Quote:
How come knowledge of how we hear is not applied just the same in acoustics? Is that it is more complicated to understand than the limitation of high frequency audibility? Or is it, that as I suspect, we are as stubborn as the next guy and won't change our views in the face of science and listening tests?

It is applied in exactly the same way with acoustics. Please point out where I've made any claim to the contrary.
post #697 of 873
Quote:
Originally Posted by JD in NJ View Post

The picture you post does show differences, albeit small while within the commonly accepted range of human hearing. That is worth taking to the next step of determining via ABX double blind testing whether or not humans can consistently differentiate two of the interconnects from each other. If so, we can begin talking about what sounds 'better'. All that being said, the interconnect with the flattest curve certainly looks to be the most likely candidate for true reproduction of sound.

That graph is showing the frequency response of the cable in isolation. In practice you'd see much smaller differences measuring the acoustical response of the entire system with one cable vs the other. You then still don't need to DBT the cables. There have been plenty of tests over the years regarding the human ear's sensitivity to roll off on the high end, just reference them.
post #698 of 873
Quote:
Originally Posted by JD in NJ View Post

What? That's hard to get across because it's claptrap. If it's not audible, then by definition you can't hear it, so it simply cannot be an improvement, QED.
You read the same post I was answering? Because if you are, why do you say the difference is inaudible? He clearly said it was: "I don't need a DBT to indicate that removing a 15db null from a room with bass traps is audible..." To which I said the fact that acoustic differences is audible is not interesting to us. What is interesting is if audible differences are positive or not.

He is putting up the usual mistaken idea that just because there are audible differences, bias takes as back seat. I have shown this to be false using formal listening tests. You think a person buying a bunch of acoustic contraptions and putting them on his walls is not inclined to think it had a positive difference? If so, why do we worry about the same thing when a person buys a fancy cable?

So no, what is "claptrap" is pretending that science and listening tests only have value in cable comparisons and not acoustics in a room. And defending subjective sighted evaluations based on gut feelings of how audio science works, than its reality.
Quote:
The first step is determining whether there's a difference at all, which is best done with measuring equipment and a rigorous test procedure. If a difference can be identified, then we can proceed to see whether people can hear it, and if so whether or not they like it.
In acoustics, we all acknowledge that there is a difference. Yet, no one who believes as such on this forum, is willing to take your second step. Instead of either running their own tests, or believing authoritative published, peer-reviewed tests of others, they believe what they have read on these forums. You either believe in science or you don't.
Quote:
The picture you post does show differences, albeit small while within the commonly accepted range of human hearing. That is worth taking to the next step of determining via ABX double blind testing whether or not humans can consistently differentiate two of the interconnects from each other. If so, we can begin talking about what sounds 'better'.
And that is the process I like to see people apply to acoustics. Yet in a year of arguing about with many members here, not one has decided to go there. They stick like glue to their past understanding of acoustics, as if no one has presented anything to them.
post #699 of 873
Describe how you go about performing controlled blinded testing of acoustic treatments in your own home or showroom.
post #700 of 873
Quote:
Originally Posted by amirm View Post

You read the same post I was answering? Because if you are, why do you say the difference is inaudible?

No, well, yes I did read that post but I was answering your statement which was quoted in my post... Which is why I quoted it in the first place. I do indeed care if a difference in my system, paid for with my hard-earned dollars, provides an improvement which by definition must be audible. Alterations that don't even pass the first test of changing the electrical signal in some fashion are not worth even pondering to me. I'm not buying jewelry for my living room. I do not want anyone else or my own gullible self telling me "this is better" when there's no difference at all.
post #701 of 873
Quote:
Originally Posted by amirm View Post

believing authoritative published, peer-reviewed tests of others, they believe what they have read on these forums.

Care to provide these 'authoritative published, peer-reviewed tests' that demonstrate audible difference between $5000 cables and those from monoprice?
post #702 of 873
Quote:
Originally Posted by xianthax View Post

Care to provide these 'authoritative published, peer-reviewed tests' that demonstrate audible difference between $5000 cables and those from monoprice?
He's referring to Toole's work regarding first reflections, not cables. Wait a while and the current thread will become a rehash of this previous thread.
post #703 of 873
Quote:
Originally Posted by RUR View Post

He's referring to Toole's work regarding first reflections, not cables. Wait a while and the current thread will become a rehash of this previous thread.

He's claiming that we are ignoring science. And since this entire thread is about cables, he clearly believes we're ignoring science there, so, lets see the science.
post #704 of 873
Quote:
Originally Posted by kbarnes701 View Post

Arny has answered more eloquently than I could have and his answer is exactly in line with my own thinking.

You are verging on a personal attack on me with your repeated "it's too difficult for you" line. As I, and Arny, have pointed out - it is not that it is difficult for *me* to conduct a sensible blind ABX test of acoustic treatments - it is next to impossible for anyone to do so. 

I agree with you that there "is not too much to talk about" with you. If you cannot see the difference between ABX testing cables and ABX testing acoustic treatments, so be it.

EDIT: incidentally, none of my position on the subject of 'magic cables' has anything to do with 'belief'. The notion that cables can make the differences to sound quality suggested by the cable evangelists is easily debunked by science. Belief has nothing to do with it.

Have I ever said that what fascinates me about forums is the personal angle? Audio schmaudio, no longer that interesting. Peoples behaviour tho......

Verging on an attack??? Look at this thread and the constant ridicule of the cable guys, and if I went back I;'d find you gleefully putting the boot in along with the rest of the pack. But when I emphasise a point you made (I would have a lot of difficulty in doing a dbt on room treatment) and show that then in that case you have to rely on the dbt's done by others that HAVE managed to overcome the difficulties you cannot I am then attacking you??

Now I have managed to stop laughing I ask again, in that YOU cannot do a dbt on room treatments why is it then that you ignore the results of those who can? You have already said you trust the results of competently done dbts over sighted anecdotal reports, so why in this case do you ignore these other results.

I can ONLY conclude that it is because (on the face of it) they seem to be contrary to what you believe (or maybe even more importantly) what you have publicly said. It is the PUBLIC face we need to protect on forums ya know.wink.gif

We are such a self centred and egotistical bunch. We always evaluate the other bloke from our own perspective. To you (and me btw) it is just too difficult to do a dbt on room treatments, yet we could do it on cables. So that means to that other bloke over there he too can do a dbts on cables. You know, the cable guy with his expensive racks and cable elevators all looking like it came out of a showroom, hard to access and what not. In other words, to that other guy it is NOT easy to do a cable test. Mine is an absolute pigsty and I don't give a toss, so I personally do not care.

But HE does. Additionally to him if he moves one of them then it will destroy the synergy. Whatever. Even tho you will reject it out of hand (as would I) the point is that TO HIM it is not the trivial exercise that it is to us.

Why then, using the very same reasons you do when it comes to room treatments would we not accept that it is too hard for him?

You won't accept it, got that. But you have already shown that there are different standards when it comes to *us*.

So, what exactly is science? Something we use to back up our beliefs? Then it is a tool of religion no? If science is the gathering of data from controlled experiments and forming hypotheses (or any such paraphrase) then is science some sort of absolute, something that stands apart from mere human belief? Of so, what formula or reasoning do you apply that allows you to accept science that 'proves' cables have no influence on the sound yet reject science that seems to suggest that room treatments might NOT be the universal improvement continually espoused here.

Note the distinction! The argument here is NOT that cables make no difference and treatments do. It is the conclusions/hypotheses we are talking about. Cable tests how no difference in sound...conclusion one cannot be better than the other (whatever)

Room treatment tests show that they are not universally an improvement...conclusion in most cases under the test room treatments are no improvement or worse (whatever they conclusions were).

NO ONE is trying to say there are not clear measurable differences with treatment or that indeed there is nothing that can be heard. That is trying to throw off the scent.

Do you think that just because there IS an actual difference in sound that we are somehow immune from all the human biases that (in your own minds at least) go a long way in explaining why people ARE cable believers?

That was the whole point and the valuable lesson learnt from all the harmon tests we adore. That even tho there are speakers that do sound different we nonetheless are subject to all of the bvrand name bling biases that (to us) account for why people think the uber amp sounds better than the pioneer.

So bias applies to amps, cables, glowing valves, big names on speakers but not and never room treatments?

Why?

"All" were applauding how harmon found that there is an underlying science to what pleases us when it comes to speakers, that speaker E was marked the worst when heard blind. Till it came out they were Martin Logans.

Then all the ML owners got uppity (understandably)..'well what do you expect, they were rigged tests using harmon trained people in a harmon facility against harmon speakers...'

"All'' were applauding when harmon tested various RC systems, and showed what we prefer a RC system to do. We liked that RC system D was judged the worst when heard blind. Till it came out that RC system D was audessy.

Then all the audessy owners gut uppity (understandably)..'well what do you expect, they were rigged tests using harmon trained people in a harmon facility against harmon RC system...'

All loved the research done by the same group of guys when it comes to distributed subs, how many, where and how to get better bass results in our rooms. (Inot exactly harmon research but you get the drift)

Now of course all the room treatment guys are getting uppity. Arny has just told us we can safely ignore these harmon tests for exactly the same reasons the Ml guys reject them. Because they come from harmon they are unreliable and tainted.

At least the cable guys just simply reject science.

So which is it guys, what parts of harmon research (and seans and todds etc etc) can we ignore and which can we reject?

If one is able to be honest and look into the mirror then at least one the the answers we need to consider is the all too human one. "I accept the ones I agree with and reject the ones I do not agree with, science and testing be damned".

which is the same reason we are snooty and superior when we talk down to the cable guys.
post #705 of 873
Quote:
Originally Posted by terry j View Post

Now of course all the room treatment guys are getting uppity. Arny has just told us we can safely ignore these harmon tests for exactly the same reasons the Ml guys reject them. Because they come from harmon they are unreliable and tainted.

At least the cable guys just simply reject science.

So which is it guys, what parts of harmon research (and seans and todds etc etc) can we ignore and which can we reject?

If one is able to be honest and look into the mirror then at least one the the answers we need to consider is the all too human one. "I accept the ones I agree with and reject the ones I do not agree with, science and testing be damned".

which is the same reason we are snooty and superior when we talk down to the cable guys.

There is a pretty large difference in the rejection rational.

When you have one study that contradicts many other studies, its very natural and quite scientific to question the results. There have been a number of times in the history of science when a study was released purporting to re-write the science books only to later to be found to have serious flaws or un-reproducible results. As a result many scientists take the stance of "Extraordinary claims require extraordinary evidence". It doesn't mean the Harmon study is blatantly false, but , you don't throw out years of studies with a single conclusion without a similar level of evidence to suggest the conclusion was wrong, one study doesn't cut it. If the study is independently reproduced, you'll find a lot more support for it.

The cable situation is completely different. We aren't questioning the testing methodology or debating preconditions. We aren't debating a contradiction of years of studies. There is nothing to debate, there is no evidence.
post #706 of 873
Quote:
Originally Posted by amirm View Post

Quote:
Originally Posted by xianthax View Post

Here is a measurement I performed of different interconnects:

i-fPbXgsF-XL.png

You would look at that difference and using knowledge of how we hear, say that the drop off in the ultrasonics is not audible.

I would also use my knowlege of electronics to know that some or all of these interconnects are not standard home audio components.

In short, the data and indeed the whole post has a certain strange odor.

A little searching shows that we've seen this picture before in the following post:

http://www.avsforum.com/t/1437764/pcm-audio-voltage-level-of-logical-true/30#post_22588184

In that post one there is relevant text about the involvment of a "low bandwidth cable". In short, the above post conceals relevant information. One might find it to be deceptive... :-(
post #707 of 873
Quote:
Originally Posted by xianthax View Post

He's claiming that we are ignoring science.
Yes
Quote:
And since this entire thread is about cables, he clearly believes we're ignoring science there...
No. He's comparing folks' behavior/beliefs as regards cables vs. absorption, as Terry and Bigus have correctly interpreted.
post #708 of 873
Quote:
Originally Posted by Bigus View Post

Describe how you go about performing controlled blinded testing of acoustic treatments in your own home or showroom.

It may not be necessary.

DBTs were originally invented because back in the 1970s a fair number of people believed that there were audible properties of equipment for which no corresponding measured data could possibly exist. One of the major hypothesis that DBTs were used to test was the belief that there amplifiers that measured the same but sounded different.

At this point I don't think that we have a large contingent of people who believe that our existing acoustical measurements are incapable of finding relevant differences between rooms and speakers that sound different.

While DBTs relating to testing of acoustic treatments may be difficult, there may be no need for them if we can obtain sufficient wisdom from acoustical measurements.
post #709 of 873
Quote:
Originally Posted by xianthax View Post

There is a pretty large difference in the rejection rational.

When you have one study that contradicts many other studies, its very natural and quite scientific to question the results. There have been a number of times in the history of science when a study was released purporting to re-write the science books only to later to be found to have serious flaws or un-reproducible results. As a result many scientists take the stance of "Extraordinary claims require extraordinary evidence". It doesn't mean the Harmon study is blatantly false, but , you don't throw out years of studies with a single conclusion without a similar level of evidence to suggest the conclusion was wrong, one study doesn't cut it. If the study is independently reproduced, you'll find a lot more support for it.

The cable situation is completely different. We aren't questioning the testing methodology or debating preconditions. We aren't debating a contradiction of years of studies. There is nothing to debate, there is no evidence.

There have been other dbts on room treatments? I'm not that fussed but I'm sure Amir would like your list. Especially if they contradict the one he relies upon (it will test his ability to consider contrary evidence) so it would be great if you supplied them.

We have already been told just how difficult it is to replicate these results...'almost impossible to do'....IIRC Arny even told us we needed a huge corporation with mega bucks behind it. So that really means we need these other contrary results of blind tests on room treatment you hint at.

Is there a reason that I am perceived as pro cables?? Another all too human reaction I guess. I point out the possibility that some are being double edged when it comes to considering the results of tests on room treatment must automatically mean I am also questioning the results of tests on cables. I am not, but what I AM trying to do is get to the bottom of why *we* accept some results and reject others.

Let's reverse the question. We know our stance to the cable guys...do a dbt on cables. They will either accept the evidence of their sense or stick to them by diminishing the validity of dbt's. Theoretically we do not have the luxury of rejecting dbts, our whole stance in audio depends on them. But, sadly to us they choose to reject the results we give them and so to us are and remain ignorant.

Yet *we* seem to reject findings on room treatments from dbt's. It is only one, done by a corporation with ulterior motives.

Air travel is cheap in the states is it not? So the obstacles to flying to harmon and sitting thru the tests are not that great are they? (dunno even if you can mind) But, if someone were to splash out big money to treat the room would it not be a cheap way to see if it is worth it?

In any case, I do not really believe these harmon tests are flying in the face of many earlier counter tests. But they ARE flying in the face of some audio forums 'everybody knows'. ''Everybody knows' that speakers and rooms are the most important in audio, hence room treatment is automatically a fantastic improvement'.

Well, it is only an 'everybody knows' and these vary from forum to forum. On audiogon 'everybody knows' that cables make huge differences. Not too long ago I guess 'everybody knew' the sun went around the earth, it was plain to see with your own senses.

It is the 'everybody knows' that never get examined in "groups". (different groups have different sets of 'everybody knows'....the 'everybody knows' of the KKK would conceivably be different from the 'everybody knows' of the Ebony Pride) No need to examine them, because everybody knows.

THAT is what 'science' does, it examines these 'everybody knows'.

So I'd like to see the contrary evidence from dbt's on room treatments you speak of and until then it will remain an 'everybody knows'.
post #710 of 873
Quote:
Originally Posted by arnyk View Post

While DBTs relating to testing of acoustic treatments may be difficult, there may be no need for them if we can obtain sufficient wisdom from acoustical measurements.
In Ando's study cited by Toole, Subjective preference in relation to objective parameters of music sound fields with a single echo, there's no mention of blind testing. An omission, perhaps.....

"The paired-comparison tests were conducted with 13 subjects judging which of the sound fields were preferred to hear. The first 12 s of motifs A and B (ed: two pieces of music, one of which was recorded anechoically) were chosen as source signals.

Preference scores were obtained by giving scores +1 and -1 according to positive and negative judgements, respectively. For no preference judgement between the sound fields, they were given zero. The normalized scores for all sound fields (F) and all number of subjects (S), and then dividing the factor of S(F-1). The positive scores, for example, indicate what percent remains of the positive judgement to the sound field, after subtracting that of the negative."
post #711 of 873
Quote:
Originally Posted by arnyk View Post

I would also use my knowlege of electronics to know that some or all of these interconnects are not standard home audio components.

In short, the data and indeed the whole post has a certain strange odor.

A little searching shows that we've seen this picture before in the following post:

http://www.avsforum.com/t/1437764/pcm-audio-voltage-level-of-logical-true/30#post_22588184

In that post one there is relevant text about the involvment of a "low bandwidth cable". In short, the above post conceals relevant information. One might find it to be deceptive... :-(

I'm pretty confused as to what was going on in that thread but it appears that the point of this graph is "what happens at high frequency when you don't match the impedance of your transmission line" ?
post #712 of 873
Quote:
Originally Posted by terry j View Post

There have been other dbts on room treatments?

There is tons of research going on constantly in this space, just a couple examples:

Effects of spatial and temporal integration of a single early reflection on speech intelligibility
The influence of masker type on early reflection processing and speech intelligibility
post #713 of 873
Quote:
Originally Posted by xianthax View Post

Quote:
Originally Posted by arnyk View Post

I would also use my knowlege of electronics to know that some or all of these interconnects are not standard home audio components.

In short, the data and indeed the whole post has a certain strange odor.

A little searching shows that we've seen this picture before in the following post:

http://www.avsforum.com/t/1437764/pcm-audio-voltage-level-of-logical-true/30#post_22588184

In that post one there is relevant text about the involvment of a "low bandwidth cable". In short, the above post conceals relevant information. One might find it to be deceptive... :-(

I'm pretty confused as to what was going on in that thread but it appears that the point of this graph is "what happens at high frequency when you don't match the impedance of your transmission line" ?

Not at all. The point of this graph's contents appears to be what happens if you search out some interconnect cables that were tricked up by their manufacturers to roll off the highs at much lower frequencies than usual.

In this context, with relevant descriptive text intentionally removed from where it once existed, the intent does not appear to be clarity or relevance.
post #714 of 873
Quote:
Originally Posted by terry j View Post

We have already been told just how difficult it is to replicate these results...'almost impossible to do'....IIRC Arny even told us we needed a huge corporation with mega bucks behind it. So that really means we need these other contrary results of blind tests on room treatment you hint at.

I'm somewhat confused by this point. I assume we're talking about the same paper. (http://www.aes.org/tmpFiles/elib/20130116/13686.pdf)

If so, there isn't any new data there, that is, it isn't the results of a DBT or new research that was done. Its an review piece combining research done by others into a cohesive position. The cost of reproducing that paper is just the time to read the related publications and form your own interpretation.
post #715 of 873
Quote:
Originally Posted by xianthax View Post

I'm somewhat confused by this point. I assume we're talking about the same paper. (http://www.aes.org/tmpFiles/elib/20130116/13686.pdf)

If so, there isn't any new data there, that is, it isn't the results of a DBT or new research that was done. Its an review piece combining research done by others into a cohesive position. The cost of reproducing that paper is just the time to read the related publications and form your own interpretation.

thanks for the earlier link(s), however they were one and the same, so thanks for the link. I won't read it, tbh not really my cup of tea. Might be good for amir tho.

This link here I have seen years ago, doubt it is what is under discussion.

Still, can I meet your 'confused' and raise you mine?smile.gif The part you quoted of my post was referring to posts made by others earlier in the thread, that's all. It was thought to be self evident that to do a dbt on room treatments was nigh on impossible. For some reason that is then used as a reason to discount any results that have been done. As I don't get it myself I have asked for clarification on why that might be. Have not heard back yet other than arny saying how unreliable it is because it comes from harmon. Yeah, I know.

He also tried to make a point that dbts are only suitable for testing very small differences. When we can measure differences then blind tests are not needed for some reason. I guess that can only come from the errornous idea that preference is not a suitable thing to test for with a dbt. That objection falls aside pretty quickly if you simply think a dbt is useful in avoiding biases which is the heading under which room treatments (and the testing of) would fall.
post #716 of 873
Quote:
Originally Posted by kbarnes701 View Post

Yes - I'm referring to that speaker - the same one used by so many movie mixing and editing rooms all over the world wink.gif

That's nice. I presume they all use treatment that I and many others would find aesthetically unacceptable in a domestic living room in those "movie mixing and editing rooms." So, not terribly relevant, unless one's talking about the need for "room treatment" as a band-aid to cover for speaker design flaws such as poorly controlled midrange directivity.

Again, with better speakers room mutilation is not required. In fact, it usually hurts more than it helps. But with speakers that have specific flaws, such as poor pattern control in the midrange, there are band-aids one can affix to room walls to round the edges of the speakers' design flaws to some degree.
post #717 of 873
Quote:
Originally Posted by xianthax View Post

Quote:
Originally Posted by terry j View Post

There have been other dbts on room treatments?

There is tons of research going on constantly in this space, just a couple examples:

Effects of spatial and temporal integration of a single early reflection on speech intelligibility
The influence of masker type on early reflection processing and speech intelligibility

The second reference leads to just an abstract, not the paper itself.

The paper itself appears to be at:

http://www.sigproc.uni-oldenburg.de/download/papers/SP2011_5.pdf

I hesitate to further distract the thread from its actual purpose which is audio cables, but when references are misleading, incomplete, or unproductive, I can at least address that.
post #718 of 873
Quote:
Originally Posted by DS-21 View Post

Quote:
Originally Posted by kbarnes701 View Post

Yes - I'm referring to that speaker - the same one used by so many movie mixing and editing rooms all over the world wink.gif

That's nice. I presume they all use treatment that I and many others would find aesthetically unacceptable in a domestic living room in those "movie mixing and editing rooms." So, not terribly relevant, unless one's talking about the need for "room treatment" as a band-aid to cover for speaker design flaws such as poorly controlled midrange directivity.

Again, with better speakers room mutilation is not required. In fact, it usually hurts more than it helps. But with speakers that have specific flaws, such as poor pattern control in the midrange, there are band-aids one can affix to room walls to round the edges of the speakers' design flaws to some degree.

 

Yeah - perhaps all those studios like Sony, Warner etc can't afford proper 'audiophile' speakers... they probably buy crappy speakers and then use treatments as a 'band aid' to disguise their flaws. That must be how it works. Thanks for enlightening me. Perhaps you ought to send your list of 'properly designed' speakers to the studios - think hw much money they'd save by having speakers that can ignore room modes and reflections!

post #719 of 873
Quote:
Originally Posted by terry j View Post

thanks for the earlier link(s), however they were one and the same, so thanks for the link. I won't read it, tbh not really my cup of tea. Might be good for amir tho.
It would be my pleasure to explain what it says. The paper looks into an aspect of intelligibility of speech in the face of reflections. It is stated in its introduction:

Early reflections are mostly defined as reflections arriving within the first 50 ms after the direct sound, and are considered to be useful for speech intelligibility as they can be integrated with the direct sound [3, 4, 5, 6]… The benefit of early reflections for speech intelligibility has been examined in several studies [4, 7, 8]. More recently, Bradley et al. [5] showed that the energy in seven early reflections arriving within the first 50 ms after the direct sound can be as beneficial to speech intelligibility in noise as the energy in the direct sound. Bradley’s studies were extended by Arweiler et al. [6], who used early reflections from the first 55 ms of a realistic room impulse response. Contrary to Bradley’s investigations, they found that the improvement in speech intelligibility in noise is greater for increased direct sound energy than for increased early reflection energy.

Translation in English smile.gif, research based on listening tests shows that the early reflections help add power to the direct sound and thereby, increase intelligibility of speech. The purpose of the research here is to determine if the power of reflections is added one for one to the direct sound, or some lesser ratio. They set up a study with a single reflection while varying the location of noise. Here is what they find:

”For the delay factor, no significant differences in SRT were found between the reference condition and thresholds for delays of 10 ms and 25 ms. This suggests that a single frontal reflection can be fully integrated with the direct sound up to 25 ms."

Remember that sound travels at the speed of 1.1 feet per millisecond. So what the above is saying is that if the reflection path is at or below 27 feet (25 milliseconds), the energy of reflection gets added one-for-one to the direct sound to help intelligibility. In other words, there is nothing but goodness from having such reflections in our domestic (small as compared to public space) listening rooms. The next time increment they tested was 50 milliseconds. At that point, we lost about 1 dB of contribution from the refection. So even there we are still good. It is not until we get to 200 milliseconds where we lose the bulk of the advantage from these reflections. That is why we worry about *late* reflections when it comes to speech, not early/first reflections.

It should be abundantly clear that this research published in 2011, is completely and equivocally consistent with the view of acoustic science as I have been presenting. In no way does it show dissent or an evolving view as xianthax presented. Recall that I talked about the Bradley research on page 6 of this thread:
Quote:
Originally Posted by amirm View Post

Listening Tests:
The foundation of our understanding of reflections is through countless other listening tests conducted since Haas performed his landmark work. In the interest of brevity (yeh, right biggrin.gif), I will only cite a few. There is at least 10X more if you care to see them.

First up is Dr. Bradley of Canadian National Research Council (a non-profit acoustic research organization). Dr. Bradley has PhD from your neck of the woods (Imperial College at the University of London) with the specialty of “electroacoustic enhancement systems in rooms.” He and his counterparts (Sato and Picard) set up a simulation of room reflections using an array of speakers, each of which could be driven to act like a reflection in a real room and therefore their effects examined under controlled situation. Their goal was to determine the effect of room reflections on speech intelligibility – the very point you make in your FAQ. Here is the conclusion in their peer reviewed paper published in the journal of Acoustic Science of America (ASA):

”This paper presents the results of new studies based on speech intelligibility tests in simulated sound fields and analyses of impulse response measurements in rooms used for speech communication. The speech intelligibility test results confirm the importance of early reflections for achieving good conditions for speech in rooms. The addition of early reflections increased the effective signal-to-noise ratio and related speech intelligibility scores for both impaired and nonimpaired listeners. The new results also show that for common conditions where the direct sound is reduced, it is only possible to understand speech because of the presence of early reflections. Analyses of measured impulse responses in rooms intended for speech show that early reflections can increase the effective signal-to-noise ratio by up to 9 dB. A room acoustics computer model is used to demonstrate that the relative importance of early reflections can be influenced by the room acoustics design.”

So no, this is not just some outlier biased research from Harman as has been said by the vocal members here. The consensus in the industry is quite strong and is the view of science I have been presenting. How else would a random pick by xianthax agree with it?
post #720 of 873
WTF are you talking about.

Its been known and accepted that first reflections can improve speech intelligibility for decades, since at least the work of Haas in circa 1950.

No one is debating that. But it is only one small aspect of why or if you treat a room, not the entire picture.

Toole's review piece assembles a selection of work he believes is pertinent, hand waves away effects he believes are immaterial, and declares that there is no need to treat the room.

Not everyone agrees.
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