IsoAcoustics Isolation Feet - Does it really make positive effect or fancy accessories

[Mart68]

I would hope that a professional reviewer would be better at perceiving those differences than the average hifi show attendees.

Hope is the right word!

I think there is really only a difference between trained and untrained listeners in terms of being able to perceive small differences, they hear harmonic distortion at much lower thresholds, for example, because they've specifically trained to do that.

I really don't know if Fremer has undergone such training (I suspect not), but if not then he's no better than you or me or a man on the street. Just being an audio journalist and 'listening critically' does not alone incur any special skills. I think to claim that it does would require some supporting evidence.

 

[kemmler3D]

maybe some people hear differences reliably that our measurements can’t detect.

Microphones and analyzers are many times more sensitive than human hearing, so... How do you propose that might happen?

When we throw around terms like “all” in the face of even limited evidence to the contrary, we close the door on exploring possible improvements to things we care about that might actually matter. None of us should be so certain “all” the time.

I haven't even closed the door on Bigfoot or aliens, but in order to stop saying they're not real, or that cables don't matter, honest people need to see hard evidence. I'd love to see the frontier of audio production and listening actually move forward, but saying statistics are hard to come by and Fremer seems like a sharp dude are not hard evidence, or even suggestive that hard evidence exists.

 

[knownothing]

Microphones and analyzers are many times more sensitive than human hearing, so... How do you propose that might happen?

And yet, neither you nor anyone else I have engaged either on this topic can currently devise of a microphone and analyzer set up capable of determining how well a stereo system can reproduce soundstage as experienced by a listener seated in the sweet spot. Let alone applying such a measurement system on currently available hifi gear. This in spite of the fact that “Microphones and analyzers are many times more sensitive than human hearing.”

Soundstage, including listener perceptions of width, height, depth and placement of instruments and voices in a stereo soundscape is one of the critically important and interesting factors in hifi reproduction. Yet we have no reproducible protocol or machine available to objectively measure and report on the performance of a component or system of components with regard to soundstage reproduction in a listening room.

This fact alone suggests to me that measurements may be the beginning of the story for assessing performance of audio equipment, but they are far from providing the whole story. Our hearing capabilities evolved over a very long period of time to allow hominids to track prey and avoid predators in space. Our ears and brains are very sensitive to the differential timing and loudness in how and when sounds hit our heads. Jitter, frequency response, and SINAD measurements are totally inadequate to model this phenomena.

Many but not all deep neural network audio models capture brain responses and exhibit correspondence between model stages and brain regions

This study presents a comprehensive analysis of the extent to which contemporary neural network models can account for auditory cortex responses; most, but not all, trained neural network models provide improved matches to auditory cortex responses compared to a classic baseline model of the...

journals.plos.org

It is a work in progress, but I think it is sufficient to say that our current machine based analyses of sound reproduction as a proxy for how that will be experienced in room by different listeners are not presenting the full story. And furthermore there are different design choices made by equipment manufacturers tuned in their shop by ear that are not fully revealed by our current set of accepted measurements but that result in real differences that are detectable by at least some human listeners.

kn

 

[MAB]

You said in post #373 you understood sample statistics.

Well, apparently Fremer was better than 39% of the people who took the test described in the WSJ article who were unable to distinguish between the sound of one cable set up or the other.

This demonstrates you know nothing about statistics, and also is predicated on the supposition that Fremer actually heard a difference.

 

[knownothing]

Hope is the right word!

I think there is really only a difference between trained and untrained listeners in terms of being able to perceive small differences, they hear harmonic distortion at much lower thresholds, for example, because they've specifically trained to do that.

I really don't know if Fremer has undergone such training (I suspect not), but if not then he's no better than you or me or a man on the street. Just being an audio journalist and 'listening critically' does not alone incur any special skills. I think to claim that it does would require some supporting evidence.

I guess we would have to do an ABX human subject study with adequate replication and controls to test your null hypothesis that Fremer and other audio equipment reviewers have average listening skills no better than the general population.

 

[knownothing]

You said in post #373 you understood sample statistics.

This demonstrates you know nothing about statistics, and also is predicated on the supposition that Fremer actually heard a difference.

What I stated was a recapitulation of the information from the article. I submit that the information provided in the WSJ article was not consistent with the null hypothesis that Fremer and Atkinson were not able to distinguish a difference in the two blind set ups. I did not make a claim that they were statistically significant. If the two reviewers had failed miserably at the test, that would be something to crow about, but according to the article’s author, they did not fail, so it remains anecdotal information, but anecdotal information that does not refute nor does it prove my point.

kn

 

[kemmler3D]

neither you nor anyone else I have engaged either on this topic can currently devise of a microphone and analyzer set up capable of determining how well a stereo system can reproduce soundstage as experienced by a listener seated in the sweet spot. Let alone applying such a measurement system on currently available hifi gear. This in spite of the fact that “Microphones and analyzers are many times more sensitive than human hearing.”

This is and isn't true. Soundstage is a gestalt perceptual effect that depends on an interaction between recording, room, and speakers. Probably in that order. Predicting the broad character of a soundstage is not super hard based on the characteristics of the speaker. Wide dispersion, OB, omni ~ "you are there" and narrow, accurate dispersion ~ "they are here".

Getting more specific than that is hard, like trying to predict if you're going to enjoy a certain wine with dinner via chemical assay, when we don't even know what the dinner is.

The inability to measure soundstage is not because the inputs to it aren't measurable, but because as far as I know a quantitative model relating those inputs and perception hasn't been developed.

And, I think it's very scientifically implausible that cables or the vast majority of electronics could affect soundstage no matter how often the Fremers of the world say they do. Based on what we know about stereo hearing I think there's nothing a cable can do to affect it materially.

there are different design choices made by equipment manufacturers tuned in their shop by ear that are not fully revealed by our current set of accepted measurements but that result in real differences that are detectable by at least some human listeners.

Like what?

 

[Mort]

devise of a microphone and analyzer set up capable of determining how well a stereo system can reproduce soundstage as experienced by a listener seated in the sweet spot.

Nor can they determine when you will think a volume is 'too loud' but that doesn't stop us from measuring volume.

 

[knownothing]

Like what?

Some manufacturers have a “golden ears” on staff to determine whether results of design decisions for new gear are consistent with the “house sound”.

There are of course egregious examples of gear in the development process measuring great on the bench but not performing well when actually listened to.

It’s Alive: The Process Of Bringing New Pro Audio Products To Life - ProSoundWeb

Product development is an undertaking that begins with an idea or concept, and most of the best ideas come by way of filling a need.

www.prosoundweb.com

And there is discussion of this topic on this site.

Dan D'Agostino interview on measurements

I posted this on another thread but it is too interesting and deserves its own discussion. Dan is a legendary amp designer formerly from Krell and nowadays with his own company. Went from designing deeply based on measurements on the later Krell days to less reducing distortion and more...

www.audiosciencereview.com

Just a few examples.

kn

 

[MarkS]

In the cable test under discussion, the speakers with different cables were in different positions in the room. Also they were not the exact same speakers, but different samples of the same model. Every speaker has sample-to-sample variations. According to measurements, both of these effects (positioning and sample variation) are expected to be larger than any cable-caused differences.

I'm happy to believe that Fremer has better ability to hear small differences than the average show attendee.

We also know for an abso!ute fact that Fremer believes he hears differences that provably do not exist. This was revealed by l'affaire MoFi, in which vinyl records that Fremer had praised for their no-digital-grain analog purity turned out to have been digitized before beging converted back to analog.

 

[kemmler3D]

Some manufacturers have a “golden ears” on staff to determine whether results of design decisions for new gear are consistent with the “house sound”.

Right but what design decisions? What exactly are they changing and hearing that we can't measure?

There are of course egregious examples of gear in the development process measuring great on the bench but not performing well when actually listened to.

Which well-measuring products are generally agreed to sound egregiously bad? This truism is often repeated but personally I can't think of any.

 

[knownothing]

Right but what design decisions? What exactly are they changing and hearing that we can't measure?



Which well-measuring products are generally agreed to sound egregiously bad? This truism is often repeated but personally I can't think of any.

Hmmm, to answer to first question, I think the Acoustic Research engineer might not reveal specifics of design changes in a YouTube post about their company’s development process.

On your second question, in the 2nd article I posted there was a specific description about a design element that measured well but did not sound good and required a later work around. If they hadn’t listened to it and instead only relied on meter readings, they would have shipped a poor sounding product.

“I recall one instance when we were building a coil EQ and discovered that the prototype was noisy. As a solution, the engineer sourced a series of induction coils with individual shields, and after he had retrofitted the parts, he said it worked perfectly. Not so!

Although electronically it tested fine, it sounded absolutely awful. I sent him back to his cave and told him not to come back until it was fixed. He discovered that the small shield collapsed the coil’s natural magnetic field, causing the tone to shift. The problem was solved by building a mu-metal box around the complete EQ section to shield the sensitive coils from the power supply’s magnetic field.”

 

[knownothing]

We also know for an abso!ute fact that Fremer believes he hears differences that provably do not exist. This was revealed by l'affaire MoFi, in which vinyl records that Fremer had praised for their no-digital-grain analog purity turned out to have been digitized before beging converted back to analog.

I had not heard about this - LOL. I think MoFi owes me some money as a part of their settlement. No matter what, the Ultradisc of Monk’s Dream is best sounding LP in my collection. Must be the excellent digital master…

 

[antcollinet]

So maybe some people hear things the rest of us don’t, and maybe some people hear differences reliably that our measurements can’t detect.

Or - as has been clearly pointed out - the test was not set up to sufficiently control for tells. In particular two differnet sets of speakers (with unit to unit variance) combined with different in room positioning. They are bound to sound different even with the same cable. And to an extent far greater than cables can cause.

 

[antcollinet]

If someone can reproducibly hear a difference that you can’t measure, instead of saying their mind or their hearing is broken, maybe it’s your measurement device that needs be improved.

so far no-one has adequately demonstrated this.

 

[antcollinet]

Well, apparently Fremer was better than 39% of the people who took the test described in the WSJ article who were unable to distinguish between the sound of one cable set up or the other.

Or - as has been clearly pointed out - the test was not set up to sufficiently control for tells. In particular two differnet sets of speakers (with unit to unit variance) combined with different in room positioning. They are bound to sound different even with the same cable. And to an extent far greater than cables can cause.

 

[antcollinet]

Some manufacturers have a “golden ears” on staff to determine whether results of design decisions for new gear are consistent with the “house sound”.

There are of course egregious examples of gear in the development process measuring great on the bench but not performing well when actually listened to.

It’s Alive: The Process Of Bringing New Pro Audio Products To Life - ProSoundWeb

Product development is an undertaking that begins with an idea or concept, and most of the best ideas come by way of filling a need.

www.prosoundweb.com

And there is discussion of this topic on this site.

Dan D'Agostino interview on measurements

I posted this on another thread but it is too interesting and deserves its own discussion. Dan is a legendary amp designer formerly from Krell and nowadays with his own company. Went from designing deeply based on measurements on the later Krell days to less reducing distortion and more...

www.audiosciencereview.com

Just a few examples.

kn

You realise all you are doing here is quoting audio company marketing material - in which they are trying to create a "mystique" to help them sell. None of this demonstrates anything valid in terms of science or engineering.

I suggest you just go and continue drinking the koolaid. You are so deep in it you can't even see how deep you are. Non of your arguments have any validity here.

 

[kemmler3D]

Hmmm, to answer to first question, I think the Acoustic Research engineer might not reveal specifics of design changes in a YouTube post about their company’s development process.

So you know that they make audible tweaks that can't be measured, but you don't actually know of any such tweaks. I will wait for examples before I accept this premise, nothing personal.

Speaking from experience as an audio marketer, audio marketers are typically short on concrete differentiators and long on BS to sell their products. When engineering comes up with a real improvement we typically talk about it as much as we can. Audible trade secrets? An odd thought when reverse engineering audio gear is easier than parallel parking for top engineers.

Although electronically it tested fine, it sounded absolutely awful. I sent him back to his cave and told him not to come back until it was fixed. He discovered that the small shield collapsed the coil’s natural magnetic field, causing the tone to shift

Sounds like the engineer messed up the filter response while fixing the noise problem. This would be eminently measurable, but the engineer didn't bother to measure it at the time.

I think this basic misunderstanding is behind most or maybe all of this "some things measure good and sound bad" / "some things can be heard but not measured" narrative.

As far as I know everything that can be heard can be measured, in theory. But just because you can hear something and certain measurements exist, doesn't mean the appropriate measurement to characterize what you heard has actually been performed already.

Not having data on hand to explain what you hear does not mean the data couldn't be gathered.

An engineer optimizing for noise and accidentally impairing frequency response doesn't poke a hole in audio science, it's just a simple oversight. It does show why listening is an important part of the process (catch mistakes) but it doesn't show that ears have secret magical properties.

 

[RexrothPigeon]

@knownothing - There is tremendous incentive for audio manufacturers to find evidence that important audible differences exist but cannot be measured. And yet there is no evidence to support that position. Measuring instruments are many, many times more sensitive and accurate than is human hearing, and every time someone thinks they have discovered a category of sound for which they are not, it turns out to be fool's gold.

As a supporter of science I am happy to admit that there remains some possibility, however slight, that there exist sonic qualities we can hear but somehow cannot be measured, but anyone who honestly considers the available facts (and there are SO many! This topic has been gnawed on for decades!) will arrive at the conclusion that the probability is exceedingly remote, and that the discovery of such qualities would turn established science on its head and deliver its discoverer fame and admiration.

 

[GabrielPhoto]

@knownothing - There is tremendous incentive for audio manufacturers to find evidence that important audible differences exist but cannot be measured. And yet there is no evidence to support that position. Measuring instruments are many, many times more sensitive and accurate than is human hearing, and every time someone thinks they have discovered a category of sound for which they are not, it turns out to be fool's gold.

As a supporter of science I am happy to admit that there remains some possibility, however slight, that there exist sonic qualities we can hear but somehow cannot be measured, but anyone who honestly considers the available facts (and there are SO many! This topic has been gnawed on for decades!) will arrive at the conclusion that the probability is exceedingly remote, and that the discovery of such qualities would turn established science on its head and deliver its discoverer fame and admiration.

Exactly. If they had even the most minute piece of real evidence to share, they would add it all over their ads instead of the usual BS romantic prose they use