Speaker Performance - Spikes, platform, etc.??

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Steve

Speaker Performance - Spikes, platform, etc.??
« Reply #60 on: 10 Jul 2005, 09:11 pm »
Hi Ethan.

     I have to admit I disagree with alot of your comments. I think they are getting a little too extreme. Of course I try to avoid either extreme, in between usually leads to the truth.

Steve,
You mentioned the ear/mind is too fragile for individual, accurate appraisal, yet stable enough to provide proof in a test?

>"Yes, though of course it depends on how you test.">>


Interesting. You are 100% sure the administrator can make sure Nothing distracts the listeners? I don't see how you can make that statement, since you indicate/mention below, in your own comments, that this isn't the case (I will also give an example).


> "My point is that casual listening over time is not reliable because so many other things affect what we perceive. ">

What do you have to support your point in way of facts? And if the ear/mind is that variable how can one support an AB test as factual?

 I read of an ABX test (some years ago), performed by an expert (I am not denying his expertise). The administrator concluded the test was performed satisfactorily. When all was said and done, the subjects were later interviewed and explained they simply ignored the X portion of the test as it was getting so confusing. This leads to some questions.

1) The expert did Not know what was influencing the subjects as they simply ignored the X portion, but he didn't know it.

2) The test was "confusing", so how many others are confused and influenced when subjected to testing? We can't just assume this to be the case.

3) How was the result of this test infuenced by these distracting influences?

4) What is actually going on, mentally, or physically, when testing, Anytime? How does the administrator actually know what the subjects are thinking in any test? I think your position is erroneous on this matter.
 

>"And moving even a few inches to one side or the other can make a very large change in perceived frequency response due to comb filtering off nearby surfaces. So you play some music, then get up and put ...">

So how are the subjects of any test keeping their heads perfectly still and the results be accurate?

 I just gave an example, and you just gave an example of instability that can easily cause an erroneous result with any test, whether mentally or physically.
Here is another example you provide Ethan.
   
> "But you can't even listen to the same recording twice, with nothing changed, and perceive the same depth.">

So how can an AB test be so fool proof when the ear/mind mechanism changes so easily? The odds are actually heavily in favor of "No sonic difference" being the conclusion/ the result.

And how can multiple, even dozens, of listening comparisons during the test result in accurate results when you just stated that even two will sound different? What are the subjects to think and respond?

 >"This is why a blind A/B test, where A and B are switched very quickly, is needed for stuff like this.">

Do you have proof that even this procedure is correct? See Above.
 
And again I ask, what Decibel level is used? Is there a standard?
Again I ask, do you have an AB test whose conclusion states the results are "fact" or "proof"? If not, then we can not exaggerate the results as fact or proof, can we?


>"The changes from spikes, or iso pads, under loudspeakers will affect frequency response.">

A simple test. Use pads and then use the spikes, keeping the speakers at the same height.

< "And again getting back to the original discussion, if putting iso pads under a CD player did affect imaging, you could easily measure that with test signals.">

An interesting experiment Scott and I did the other day. We checked out five different feet under a Cary CD player. Not blindfolded, so this portion doesn't count, but we went one step further (saw this on a post several years ago). We explained the sonic differences we heard. The result is we heard the same sonic differences. Now, one word of caution.

1) We both lied to each other, or one lied to match the other.
2) We actually heard the same differences.
3) ESP exists (which I don't believe) so we read each others mind before we responded to each other.

I thought it was a pretty interesting experiment.


Take care.  :)

Ethan Winer

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« Reply #61 on: 10 Jul 2005, 09:18 pm »
Max,

> any nay-saying on your part is also just guessing. <

See my July 7 post about howling at the moon to cure arthritis. I don't need to try howling to know it won't work. Do you need to try it to know it won't work? Exactly my point! :P

The more one understands how things work, the less likely they are to give credence to an implausible hypothesis. In my book that's called progress. Otherwise we'd still be using blood letting as a medical cure. Remember, people were certain that blood letting worked for a very long time! It was the advent of scientific evidence-based research that started the downfall of such practices. Unfortunately, much of the audiophile world is still living in the dark ages. A quick visit to the Tweaks section over at Audio Asylum proves that. :o

--Ethan

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« Reply #62 on: 10 Jul 2005, 09:23 pm »
John,

> My contention is that we can hear things that cannot be quantfied via measument. <

If you have any evidence I'd love to hear it. Until then, I stand by my assertion that the state of the art with measuring is several orders of magnitude better than what is audible. On all aspects of audio, not just distortion and frequency response.

> No doubt, much of it stems from the "very real" results from isolating a Turntable, and arm from external vibrations, along with some good marketing. <

I agree with that completely. I call these things "pretend relatives," where something that is not legitimate pretends to be real because something seemingly similar is real. For example, bi-wiring is a pretend relative to bi-amping which is legitimate.

--Ethan

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« Reply #63 on: 10 Jul 2005, 09:52 pm »
Steve,

> I try to avoid either extreme, in between usually leads to the truth. <

On what do you base that? Often "middle of the road" is just wrong, and the truth really is at an extreme. Believing the world is round was once considered extreme! Or put another way: Logically speaking, just because a large number of people believe something does not make it true.

> You are 100% sure the administrator can make sure Nothing distracts the listeners? <

I think you're confusing the issues. You can't prove a negative, so I wouldn't use a blind test for that. If certain audiophiles claim they can hear a change when they put their CD player on spikes, and that claim defies all that is known about the science of audio, then the burden of proof is on said audiophiles. If they're distracted during the test, that's their problem. And if a small distraction is enough to keep them from hearing the change, how real was that change to begin with? So while a proper test may not be able to prove that spiking a CD player makes no difference, after enough test failures it's reasonable to conclude that spiking a CD player does nothing audible.

> What do you have to support your point in way of facts? And if the ear/mind is that variable how can one support an AB test as factual? <

Again, the burden is on the believers to prove a positive, not on the skeptics to prove a negative. Do spikes help a CD player or don't they? Please prove it to this skeptic by showing that you can tell which is which without looking. By the way, I have no problem with a test being done over 3 months if that's what the believer wants to do. But it must be a proper test. This came up recently elsewhere, and it was suggested that the believer could keep a diary of which "condition" he thought was in place, and as long as he couldn't tell by looking at the gear his diary could go on for months. Then, eventually, the diary would be examined for statistical significance.

> the subjects were later interviewed and explained they simply ignored the X portion of the test <

Again, that's irrelevant for all the reasons I listed above.

> Not blindfolded, so this portion doesn't count <

Not blindfolded means none of it counts.

> We explained the sonic differences we heard. <

Yep, I can just imagine the things you described. :roll: Sorry, but if you both concluded "improved imaging" or "more solid midrange" or other such non-specific wording, it's useless because such words can mean anything at all.

It's too bad you live so far from me because I am certain we could put this to bed in five minutes. I'll tweak while you listen blindfolded and tell me which is which. :D

> How accurate, in degrees, can you detect phase shift using a scope? <

Who cares? So use DSP or convolution or whatever is needed to measure the phase accurately. My point is that phase, and everything else, can be measured finely enough to determine for certain if spiking a CD player changes anything audibly.

> we can hear nuisances -70db <

Perhaps in extreme situations, like aliasing distortion where the artifacts are too far away in frequency from the fundamental to be masked sufficiently. Otherwise, 40 dB down is more like it most of the time.

--Ethan

PhilNYC

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« Reply #64 on: 10 Jul 2005, 09:53 pm »
Quote from: Ethan Winer


The more one understands how things work, the less likely they are to give credence to an implausible hypothesis. In my book that's called progress.


Interestingly, I was a huge naysayer of many of these things until I tried them.  Honestly, I would prefer if they didn't make a significant difference...it would just make things a lot easier... :o

Ethan Winer

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« Reply #65 on: 10 Jul 2005, 10:02 pm »
Phil,

> I was a huge naysayer of many of these things until I tried them. <

What things do you have in mind?

Also, you're close to me, so if you'd like to get together in person to test some of these things, and write up a joint report for the forum, I'm game. My listening environment is excellent (both of them), but if yours is too and you prefer, I'll gladly make the trip.

--Ethan

csero

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« Reply #66 on: 10 Jul 2005, 10:07 pm »
Quote from: Steve
>"And moving even a few inches to one side or the other can make a very large change in perceived frequency response due to comb filtering off nearby surfaces. So you play some music, then get up and put ...">

So how are the subjects of any test keeping their heads perfectly still and the results be accurate?
 ...


So how about creating a soundfield around the listener's head which will support the perceived image in case of head movements, not contradict it.  :D

PhilNYC

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« Reply #67 on: 10 Jul 2005, 10:10 pm »
Quote from: Ethan Winer

What things do you have in mind?


The first time someone put my CD player on brass cones, I was floored...not by how much difference it made (it wasn't earthshattering, but it was definitely noticeable, even by my wife, who is not an audiophile by any stretch), but by the fact it made a difference at all.  

One that happened to me recently was this...I am a Billy Bags Designs dealer, and I was using a PRO-33 rack for the last few year; a manufacturer's rep who happens to operate 2 towns over from me asked if I was interested in representing TAOC racks.  They are expensive ($500/shelf), and honestly I don't do much business selling racks...so the last thing I wanted to do was spend money on a TAOC demo rack and sell my PRO-33 (300+ lbs, nearly 5' tall).  But I agree for him to bring one over...and for the love of god, it was significant enough an improvement that I sucked it up and became a TAOC dealer.  

Quote
Also, you're close to me, so if you'd like to get together in person to test some of these things, and write up a joint report for the forum, I'm game. My listening environment is excellent (both of them), but if yours is too and you prefer, I'll gladly make the trip.

--Ethan


would love to get together...things are pretty swamped until August, but let's definitely plan something.  Maybe you can even come to our July NY Audio Rave (in Stamford, CT)...

maxwalrath

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« Reply #68 on: 10 Jul 2005, 10:36 pm »
Quote from: Ethan Winer


See my July 7 post about howling at the moon to cure arthritis. I don't need to try howling to know it won't work. Do you need to try it to know it won't work? Exactly my point! :P
...


What you're saying is that every person who's thought there was a slight improvement in sound after trying vibration control, and every professional reviewer who's tried feet, cones, shelves, racks, etc., is hearing things....


Being skeptical of something because there is evidence that it won't work is natural.

For someone who is very willing to pull out lots of scientific info to support your claim, it's suprising that you won't go the extra step and put your hypothesis to the test.

I think you need to realize that this is a hobby of endless A/B comparisons for a lot of us.

If you aren't willing to do the comparison, no matter how valid your reasons, there's no way you can honestly know for sure.

maxwalrath

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« Reply #69 on: 10 Jul 2005, 10:37 pm »
If you'd rather not go through a dealer when you might send the product back, I can send you my Herbies feet to try out for a week. All you have to do is ship them back.

John Casler

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« Reply #70 on: 10 Jul 2005, 11:04 pm »
Quote from: Ethan Winer
John,

> My contention is that we can hear things that cannot be quantfied via measument. <

If you have any evidence I'd love to hear it. Until then, I stand by my assertion that the state of the art with measuring is several orders of magnitude better than what is audible. On all aspects of audio, not just distortion and frequency response.

...


Ethan, I just did.

If I play a cd with 20Hz test tone in it, you can measure it, show it on a graph and tell me I will hear it.

But you cannot measure which of several instruments in a large orchestra produced the 20Hz information.


It it has dynamic range, you cannot tell me which instruments can be heard most clearly "combining" to produce that range of information.

If I play a Live Recording CD, and hear the room/venue it was recorded in you "cannot" tell me by measuring it, and printing out a graph, what kind of room/venue I will hear.

At best you may be able to look at the measurement and see it has a lot of Phase relationships.

So no doubt you can measure information, but that cannot always be translated into what we hear.

Maybe if you look at it as a "sonic recipe".

If we combine ingredients to make a dish, we can most likely analyze that dish and figure out what is in it, but that doesn't tell us what it tastes like.

Or for that matter, a dish that is "freshly made", compared to a dish that was made yesterday and re-heated today will have the same ingredients, yet taste different even though they will "analyze" the same.

Can you measure that difference?  The tongue can.

If 3-D depth of an instrument can be Measured, show me a graph or measurment chart of a violin on a chart or graph of an orchestral perfromance, and where it might be located, how loud it is playing and the notes it is playing.

If I am sitting low row center at the symphony, with my eyes closed, I can tell you that information, yet it cannot be measured, from anaylyzing the recording wit measuring devices.

Strangely enough, in my room, when I "replay" a recording of the same thing, I can also get that information.  Yet, it can't be measured.

In fact, once you get beyond test tones, it is very diffcult to measure individual instruments in an orchestra, by analyzing a recording.

The ear/brain can do this to a very high degree.

Steve

contradictory
« Reply #71 on: 11 Jul 2005, 07:56 am »
Dear Ethan,

     I think sometimes one can get so indoctrinated to the point of not seeing the forest from the trees. I couldn't help noticing that you either left out replies to my questions, or gave an answer that "one can not prove a negative", which leaves a gapeing hole in your position since you cannot adequately solve the problems your position presents.
This is my last post on this string as Ethan has made it easy to draw some conclusions.

> You are 100% sure the administrator can make sure Nothing distracts the listeners? <

>>I think you're confusing the issues. You can't prove a negative,>>

 The point is unless you can prove the administrator can eliminate all possible causes distractions (which you previously said he could), whether caused by the ear/mind/physical, or anything else, the conclusions can not be considered noteworthy. This is basic science 101 Ethan.
 
Since, by your own admission, this cannot be done you cannot account for total accuracy thru every phase of the testing. The next comment also varifies this.

 >>If they're distracted during the test, that's their problem.>>

Yet again, as stated in one of your earlier posts, "yes" the administrator does eliminate all distractions, whether mind/ear/physical. Now you conclude that distractions are possible, if not common. How can I take you seriously when you constantly contradict yourself?

In fact, you also mentioned one cannot hear the same sonics twice from the same song, on the same system. So how are the subjects to decide if any sonic changes between A and B exist, when the reference sound, by both A and B, cannot be reproduced even a second time?

>>And if a small distraction is enough to keep them from hearing the change, how real was that change to begin with?>>

How do you know what size the distractions are? ESP? Neither does the administrator, unless he has ESP.

>>So while a proper test may not be able to prove that spiking a CD player makes no difference, after enough test failures it's reasonable to conclude that spiking a CD player does nothing audible.>>

That depends on if the DBT is accurate, which, by your own comments, doesn't seem to be the case.

Me: > What do you have to support your point in way of facts? And if the ear/mind is that variable how can one support an AB test as factual? <

>>Again, the burden is on the believers to prove a positive, not on the skeptics to prove a negative.>>

So you cannot support your position? You have to be able to prove every facet of your position Ethan. The fact is, you have no idea what influences the testing.

1) You stated that a DBT test is required to eliminate all distractions because the individual can not do it by himself. An individual gets distracted.
2) Then you contradict yourself by providing information that distractions, no standard reference etc, are inherantly a part of the testing proceudre.
3) Then you shift again, stating "If they're distracted during the test, that's their problem."

So what is the truth Ethan? You flip flop more than Kerry.

Just ignoring problem after problem with statements like "we can not prove a negative" still leaves one with the problems. You have got to account for the problems, and prove they are not influencing the conclusions. Otherwise, you are wasting our time.

One also has to make sure all possible variables are accounted for (as with any objective study), that there are no weaknesses or outright gaps that could render one's conclusions suspect, or null and void. Otherwise, you have no idea if the subjects are simply answering because they do not hear a difference, are confused by the constantly differing sonics (as you state), and/or simply guessing.


>> But it must be a proper test.>>

I have asked you at least Twice what is a "proper test", but received no reply. I also haven't heard what the decibel level is for the testing, or if a standard exists.

Me: > the subjects were later interviewed and explained they simply ignored the X portion of the test <

Again, that's irrelevant for all the reasons I listed above.>>

Of course it is relevant Ethan.

1) It demonstrated that the administrator had not a clue how the subjects reacted to the stimuli, whether there were influences, whether mind/ear/etc affecting their judgement. So one has no idea whether the results are valid.
So much for your comment "yes" to the question could the administrator rid all external factors in a test.

2) That confusion (as they stated) exists in the subjects mind (distractions. (Imagine an objective test with confusion abounding, being called reliable.)

3) That the administrator didn't understand the listening process the subjects were using/thinking when listening, yet, in his ignorance, claimed the test was valid. The subjects didn't follow procedure. So do other administrators really understand if the subjects are following "proper" procedures? It is mental, maybe the administrators have ESP?

>Not blindfolded, so this portion doesn't count <

Not blindfolded means none of it counts. >>

You are hardly the judge of that.

> We explained the sonic differences we heard. <

Yep, I can just imagine the things you described.  Sorry, but if you both concluded "improved imaging" or "more solid midrange" or other such non-specific wording, it's useless because such words can mean anything at all.>>

First of all, I am an electronics engineer and Scott is a mechanical engineer. We are quite capable of expressing ourselves fully and articulately without your help or guidance Ethan.

>>It's too bad you live so far from me because I am certain we could put this to bed in five minutes. I'll tweak while you listen blindfolded and tell me which is which. >>

Well, since you sabatoged your own position by the above, plus other comments, your point is mute.

> How accurate, in degrees, can you detect phase shift using a scope? <

Who cares?>>

 Because you first stated a scope can accurately measure the phase differences, and once again, you sidestepped to another comment. How can I take you seriously if you are constantly changing your stance?

> we can hear nuisances -70db <

>>Perhaps in extreme situations, like aliasing distortion where the artifacts are too far away in frequency from the fundamental to be masked sufficiently. Otherwise, 40 dB down is more like it most of the time.>>

That is interesting. I suppose you got that figure from an AB test?
Based on your previous contradictory comments, I wouldn't put too much stock in that figure.


Take care.  :)

Ethan Winer

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« Reply #72 on: 11 Jul 2005, 11:31 am »
csero,

> So how about creating a soundfield around the listener's head <

Or, more typically, listen in a reflection free zone (RFZ) which reduces the comb filtering that's otherwise present. A glass coffee table in front of the couch guarantees the frequency response will change drastically with small head movements.

--Ethan

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« Reply #73 on: 11 Jul 2005, 11:48 am »
John,

> But you cannot measure which of several instruments in a large orchestra produced the 20Hz information. <

How is that relevant to any of this? We're going in circles because I maintain that if spikes do anything it can be measured, and you keep talking about acoustical cues embedded in the music. Apples and oranges.

> So no doubt you can measure information, but that cannot always be translated into what we hear. <

Again, what does human perception have to do with spikes?

> a dish that was made yesterday and re-heated today will have the same ingredients, yet taste different even though they will "analyze" the same. <

I really doubt they will analyze the same! The very same chemical changes that affect taste will also be measurable.

> Can you measure that difference? The tongue can. <

Labs can measure contamination from rat droppings in parts per million, even though you can't taste them until they're hundreds of times higher. (Yuck, sorry.) So yet again, here's a perfect example where science can measure to orders of magnitude beyond what humans can perceive.

> If I am sitting low row center at the symphony, with my eyes closed, I can tell you that information, yet it cannot be measured, from anaylyzing the recording wit measuring devices. <

Yes it can. I'm sure one could measure the delay to the first few reflections and determine the distance from that. Telephone systems use echo cancelling algorithms to reduce echoes, and the same kind of DSP code could tell how far a listener is from a source in a room with reflective surfaces.

> The ear/brain can do this to a very high degree. <

And measurements can best the ear/brain every time by a huge margin.

Again: If you believe that putting spikes under a CD player changes anything, please explain what is changed.

--Ethan

Ethan Winer

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Re: contradictory
« Reply #74 on: 11 Jul 2005, 12:06 pm »
Steve,

> This is my last post on this string <

Indeed. You accuse me of not understanding "Science 101" yet you dispute the validity of blind testing?

Enjoy your spikes. :D

--Ethan

csero

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« Reply #75 on: 11 Jul 2005, 02:07 pm »
Quote from: Ethan Winer
csero,

> So how about creating a soundfield around the listener's head <

Or, more typically, listen in a reflection free zone (RFZ) which reduces the comb filtering that's otherwise present. A glass coffee table in front of the couch guarantees the frequency response will change drastically with small head movements.

--Ethan


The problem is that you don't even need a reflection for the frequency response  to change drastically with small head movements. Two speakers placed 6-10 feet apart is perfectly enough.  :D

BTW feq response is changing drastically with head position in a concert hall also, and I would not call that a reflection free zone either. But all the reflections and freq changes just reinforce the beeing there feeling, because they support the perceived ambience, not destroy it.
Just room treatments without other measures will change the sound of the domestic sound reproduction from "two speakers playing in a LIVE suburban livingroom" to "two speakers playing in a DEAD suburban livingroom"

John Casler

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« Reply #76 on: 11 Jul 2005, 02:10 pm »
Quote from: Ethan Winer
John,

> But you cannot measure which of several instruments in a large orchestra produced the 20Hz information. <

How is that relevant to any of this? We're going in circles because I maintain that if spikes do anything it can be measured, and you keep talking about acoustical cues embedded in the music. Apples and oranges.

> So no doubt you can measure information, but that cannot always be translated into what we hear. <

Again, what does human perception have to do with spikes?

 ...


Hi Ethan,

Looks like you have too many Exchanges going on, and mine was slightly off topic.

My "only" contention was that you said everything we can hear can be measured, and I said there are things we hear that "can't" be measured.

That issue was entirely seperate.

For the record, and on topic, I think spiking and mass loading speakers and subs can have a a positive affect, and while I mass load my front end and amplification components, I can not claim to notice a substantial difference.

Steve

let topic die
« Reply #77 on: 11 Jul 2005, 05:30 pm »
Hi Guys,

     If I may suggest, I would let this topic die. Nothing is being gained here. We have occasionally seen this nonsense on other chat sites over the years.

     Ethan's last post says it all. He again has not provided any evidence of any kind. He again would not provide information I requested, and also sidestepped the issues I presented. Only a simple comment that I do not now believe in subjective dbt.

I wanted facts and evidence (isn't that what we are after?) but he couldn't provide a single piece of evidence, let alone good evidence, just his own rhetoric.

It is good to see, though, that you believe in minimizing/eliminating first reflections.

Take care.  :)

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« Reply #78 on: 11 Jul 2005, 05:35 pm »
csero,

> you don't even need a reflection for the frequency response to change drastically with small head movements. <

Yes, good point.

> feq response is changing drastically with head position in a concert hall also, and I would not call that a reflection free zone either. <

Other than the floor, all the other surfaces are very far away, so that avoids the most blatant comb filtering. But you are correct - the response changes all over the place regardless. And I believe that's one big reason people think something has changed even when it could not possibly have.

--Ethan

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« Reply #79 on: 11 Jul 2005, 05:39 pm »
John,

> you said everything we can hear can be measured, and I said there are things we hear that "can't" be measured. <

I continue to believe that anything audible can be measured. Maybe not the way you describe ("measure" which orchestra instrument is responsible for the 20 Hz component), but certainly the way I describe. :D

I also agree with Steve this topic has probably ceased being productive.

--Ethan