Can you hear above 20khz? Test files included.

[shadyJ]

I don’t think IMD would be that big of a factor, I actually measured a 4khz tone and a 25khz tone layered on top and did not see any side band distortions indicative of IMD out of curiosity.

What mic were you using? you would need a very good mic to measure the distortion products of those tones. You would need very good playback equipment to reproduce those tones.

 

[killdozzer]

Actually DSD sucks if you want ultrasonic response, as there is a ton of quantization noise above 20khz. DSD can’t even be mixed and edited natively, and requires conversion to pcm and back to dsd to edit in a DAW, each conversion adds additional noise. From a technical standpoint, DSD is worse than pcm, from an objective standpoint, listeners cannot differentiate between pcm and DSD.

Please explain just why are you quoting me and talking about DSD? Because SACD is DSD or what?

If so, that example was not meant to be taken literally. I'm saying any registered brain activity can not be directly translated into "buy this or that". Which >eargiant tried to smuggle behind quoting a magazine. I know what I'm talking about because I'm following these things closely. The article is published, it will get contested and peer reviewed and it will get torn to shreds. Going from "look we register some activity" to "this means "you can perceive it and prefer it"" as this arse spouts is really light years away.

 

[Pogre]

The "required answer" is clearly spelled out in the link I originally provided. It's not my fault it does not work for you. If you're still having trouble copy and paste what I highlighted in red below into a Google search. That should take you right to to the study. Please read it before you comment again:

Inaudible High-Frequency Sounds Affect Brain Activity: Hypersonic Effect
Tsutomu Oohashi, Emi Nishina, Manabu Honda, Yoshiharu Yonekura, Yoshitaka Fuwamoto, Norie Kawai, Tadao Maekawa, Satoshi Nakamura, Hidenao Fukuyama, Hiroshi Shibasaki
Journal of Neurophysiology Published 1 June 2000 Vol. 83 no. 6, 3548-3558 DOI

There is no "problem" other than the one you are trying to create, re-read post #54 which I was editing while you replied. I quoted two paragraphs for you to start with while you locate the study. Here it is again:


As requested, to make it easier for you here are not one but two paragraphs that support my comment that "Even when you don't think you hear it, you can perceive and prefer it."

But don't stop with the two paragraphs I quoted below, please take the time to read the entire study.


"Despite the fact that nonstationary HFCs were not perceived as sounds by themselves, we demonstrated that the presentation of sounds that contained a considerable amount of nonstationary HFCs (i.e., FRS) significantly enhanced the power of the spontaneous EEG activity of alpha range when compared with the same sound lacking HFCs (i.e., HCS). In parallel experiments employing exactly the same stimulus and methods, PET rCBF measurement revealed that FRS activated the deep-lying brain structures, including the brain stem and thalamus, compared with HCS. In addition, subjective evaluation by questionnaire revealed that FRS intensified the subjects' pleasure to a significantly greater extent than HCS did. We conclude, therefore, that inaudible high-frequency sounds with a nonstationary structure may cause non-negligible effects on the human brain when coexisting with audible low-frequency sounds. We term this phenomenon the “hypersonic effect” and the sounds introducing this effect the “hypersonic sound.” We do not think that the hypersonic effect is specific to the sound material used in the present study because we previously confirmed, by EEG analysis, that the same effect can be introduced by different sound sources containing a significant amount of nonstationary HFCs"

and

"In conclusion, our findings that showed an increase in alpha-EEG potentials, activation of deep-seated brain structures, a correlation between alpha-EEG and rCBF in the thalamus, and a subjective preference toward FRS, give strong evidence supporting the existence of a previously unrecognized response to high-frequency sound beyond the audible range that might be distinct from more usual auditory phenomena. Additional support for this hypothesis could come from future noninvasive measurements of the biochemical markers in the brain such as monoamines or opioid peptides."

Is that enough "led" [sic] to back up my statement for you? If you want more you'll have to read the study for yourself.

Next time, it would behoove you to actually read what one is referencing before calling them out on a statement they made.

At this point I think you owe me an apology.

That study doesn't prove anything as far as what can be heard. A hypothesis at best. More voodoo.

 

[Irvrobinson]

That study doesn't prove anything as far as what can be heard. A hypothesis at best. More voodoo.

You guys are lost. The study just measured brain activity, and it seems to prove something is going on. That isn't voodoo. Whether or not it supports anything <eargiant believes is another matter, but they measured something and got it published in a peer-reviewed journal. It's a data point, but it surprised me. Not that it's changing my buying habits one bit. 16/44.1 is what I'm doing.

 

[<eargiant]

You guys are lost. The study just measured brain activity, and it seems to prove something is going on. That isn't voodoo. Whether or not it supports anything <eargiant believes is another matter, but they measured something and got it published in a peer-reviewed journal. It's a data point, but it surprised me. Not that it's changing my buying habits one bit. 16/44.1 is what I'm doing.

That's an understatement.

I wonder if he thinks it's voodoo when an EEG scan of a brain looks different after the "witch" doctor gives the patient some dopamine.

Going from "look we register some activity" to "this means "you can perceive it and prefer it"" as this arse spouts is really light years away.

Now you've resorted to name calling, nice...

Apparently your panties are in a bunch simply because I wrote this line, "Even when you don't think you hear it, you can perceive and prefer it." So let me give it one more shot and break it down for you section by section:

"Even when you don't think you hear it,"
- The subjects in the study could not hear the ultra-sonic sounds.

"you can perceive"
- The brain scans of the subjects in the study clearly showed increased activity in specific regions associated with pleasure when exposed to the samples with inaudible high-frequency sounds. The difference in the EEGs show that they could somehow perceive the inaudible frequencies.

"and prefer it."
- When completing a subjective questionnaire, the subjects in the study claimed that they derived more pleasure, to a significantly greater extent, from the sound samples with the inaudible high frequency sounds.


These were the findings of the study and were even summarized in the conclusion of the paper.

If you think that the sentence I wrote and the findings of the study are "light years away" from each other, you have an issue with basic reading comprehension.

At this point I'm done with you. You can stick your head in the sand or up your "arse" for all I care. If you don't like the study write to the Journal, but get off my back.

 

[jinjuku]

I'm right along the standard curve for men in their mid-forties: I can't hear above 15,200 KHz

 

[mtrycrafts]

I'm right along the standard curve for men in their mid-forties: I can't hear above 15,200 KHz

But you can enjoy most everything above it, especially on the beach. Oh wait your skin reacts to that and vitamin D is created.

 

[<eargiant]

Food for thought.

I’ve been thinking about the deep-seated resistance this topic usually gets and I’ve come to the conclusion that it’s more about the personal beliefs/sensitivities and the byproducts of the hobby itself and less about the scientific method.

I get it, there’s a lot of BS in this hobby and we’re all tainted but let’s face it, few of us want to admit or even entertain the possibility that we might be missing something that is pleasurable in our audio. Especially since we can’t hear it anyway, right?

The question I have is, why do some hold our sense of hearing to a higher standard than we do any of our other senses? Why do some consider our ears to be infallible gatekeepers when acting as receptors of data that is processed by our core brain functions?

Let’s imagine for a moment that this is not an Audio related forum but a Food forum or even better, a Medical forum. Now let’s substitute some of the key components.


Heavy Argument VS No Argument

20Hz- 20Kz Music playback = Your Favorite drink (water, orange juice, etc.)

ADDED CONTENT

Inaudible HF Musical Content = Tasteless/Odorless Drug (dopamine or similar)

SENSORY PERCEPTION

2 Ears = Thousands of Taste buds

OBJECTIVE MEASUREMENT

Brain EEG Scan = Brain EEG Scan


In the examples above, neither the Ears nor the Taste Buds can detect the ADDED CONTENT (Inaudible HF Musical Content or Tasteless/Odorless Drug).

On the “No Argument” side, no one in their right mind would argue with the fact that a subject would not be able to taste the difference of his favorite drink with or without the tasteless/odorless dopamine. No one would question the fact that the dopamine would get into the brain and affect pleasure even though the taste buds did not detect it. This is a well-accepted fact.

Why do we lose our minds on Audio forums when faced with the possibility that something in the audio content may get past our ears abilities and affect our brain?

Do you really believe that something that can affect brain activity and pleasure (as proven by brain scans) can get past our taste buds but not our ears?

 

[shadyJ]

That paper isn't thorough enough for the conclusions you want to draw from it. What is says is that we can't hear stuff above 20 kHz, but we can hear some effects of ultrasonic content on that playback material in that system. The question is how was the ultrasonic content modifying the audible spectrum playback to make it different?

 

[<eargiant]

That paper isn't thorough enough for the conclusions you want to draw from it. What is says is that we can't hear stuff above 20 kHz, but we can hear some effects of ultrasonic content on that playback material in that system. The question is how was the ultrasonic content modifying the audible spectrum playback to make it different?

In my example, I should have clarified that the hypothetical "Drug" ONLY works when mixed with your favorite drink.

Right, we cannot hear sounds above 20 kHz and we can detect the effects of ultrasonic content when it is added back to the musical recording it was originally a part of...

But no, the ultrasonic content is NOT "modifying the audible spectrum playback" at all. If the audible spectrum was being modified when ultrasonic content was added back we would easily be able to measure that on a graph and show the difference. On a graph the content below 20 kHz will remain identical and unchanged with or without the ultrasonic content.

What they are saying is that when the ultrasonic content is added back to the music, it changes how we perceive the the recording. This is about a physiological change that happens to the listener and not a change to the "audible spectrum playback to make it different". So, the "audible spectrum playback" content remains identical, what changes is how we perceive it.

See the two possible explanations they cite below:

"...it is not straightforward to explain the neuronal basis of the hypersonic effect characterized by the fact that HFCs showed significant physiological and psychological effects on listeners only when presented with audible sounds. Although how inaudible HFCs produce a physiological effect on brain activity is still unknown, we need to consider at least two possible explanations. The first is that HFCs might change the response characteristics of the tympanic membrane in the ears and produce more realistic acoustic perception, which might increase pleasantness. However, this hypothesis is unlikely to explain the fact that the subjects who showed significant hypersonic effect were not necessarily aware of the difference of sounds in a conscious manner. An alternative explanation is that HFCs might be conveyed through pathways distinct from the usual air-conducting auditory pathway and therefore might affect the CNS, including the deep-lying brain structure. It was reported that the vibratory stimulus of ultrasound modulated by the human voice activated the primary auditory cortex (Hosoi et al. 1998) and was successfully recognized by people with normal hearing as well as those whose hearing is totally impaired (Lenhardt et al. 1991). Recently evidence has accumulated that stimuli outside the frequency and amplitude boundaries of an auditory neuron's receptive field can influence responses to stimuli inside the classical receptive field determined with pure tone stimuli (e.g., Schulze and Langner 1999). This modulatory interaction between inside and outside the classical auditory receptive range is noteworthy."

So it's not "modifying the audible spectrum playback to make it different" but rather that it's somehow producing "a physiological effect on brain activity". The audible content remains the same, what is changing is how we perceive (physiological) and prefer (psychological) it.

 

[mtrycrafts]

...
OBJECTIVE MEASUREMENT

Brain EEG Scan = Brain EEG Scan


...

Why is this the "objective" measure? No one validated the EEG that in fact what it means other than the EEG shows activity. Does that translates to a conscious effect? Can the person consciously have a valid judgement selection for that effect? Can the person's conscience select in a statistically valid manner or just the EEG shows some sort of reaction? Would that EEG react similarly to other stimulations? Has that possibility been tested? Why not?

How about a DBT listening test? More relevant in fact. If the person cannot differentiate between content without that ultrasonic vs with, what else is there left but the EEG is not an indicator of relevance.

 

[shadyJ]

But no, the ultrasonic content is NOT "modifying the audible spectrum playback" at all. If the audible spectrum was being modified when ultrasonic content was added back we would easily be able to measure that on a graph and show the difference. On a graph the content below 20 kHz will remain identical and unchanged with or without the ultrasonic content.

The spectral content of the graph does change below 20 kHz from the full signal to the low passed signal. Look at it closely. But it is impossible to determine how a system's behavior is affected by using extremely complex signals like music. A multi-tone test was needed here, to ensure that ultrasonic playback does not significantly modulate audible frequencies. They have not ruled out behavior by the equipment itself, or, if they have, they have said nothing about how they did account for it. I think if they tried to publish this in the JASA or JAES that detail would have been caught. The tests themselves have to be tested. You can not go by manufacturing specs; their response has to be published.

Here is a problem:
"Then, LFCs and HFCs were separately amplified with P-800 and P-300L power amplifiers (Accuphase, Yokohama, Japan), respectively, and presented through a speaker system consisting of twin cone-type woofers and a horn-type tweeter for the LFCs and a dome-type super tweeter with a diamond diaphragm for the HFCs. The speaker system was designed by one of the authors (T. Oohashi) and manufactured by Pioneer Co., Ltd. (Tokyo, Japan). This sound reproduction system had a flat frequency response of over 100 kHz."

So it turns out this test was all about justifying the ridiculous specs of some high-end gear by Pioneer. This testing isn't impartial and needed careful peer-reviewing before being published, but we don't have evidence of that since we don't know the system's true behavior under extreme wide-band content. The thing is I have seen plenty of speakers spec'd with an ultrasonic frequency range, but what I have never seen is a smooth flat response out to 100 kHz as one of the authors claim. Speakers that have these ultra-extended responses usually get pretty ragged up there, but usually no one cares since no one can hear that high anyway.

This research only proves that this particular sound system might be causing some kind of effect in the audible frequency range. It is not rigorous enough to indicate anything about human sensitivity to ultrasonic frequencies.

 

[mtrycrafts]

... This testing isn't impartial and needed careful peer-reviewing before being published, ...

I don't think that Journal can give a valid peer review as it pertains to audio signal detection by the human ear, not an EEG machine.

 

[Irvrobinson]

The thing is I have seen plenty of speakers spec'd with an ultrasonic frequency range, but what I have never seen is a smooth flat response out to 100 kHz as one of the authors claim. Speakers that have these ultra-extended responses usually get pretty ragged up there, but usually no one cares since no one can hear that high anyway.

And it wouldn't matter to this test, since they weren't measuring preference, only brain activity.

 

[Irvrobinson]

How about a DBT listening test? More relevant in fact. If the person cannot differentiate between content without that ultrasonic vs with, what else is there left but the EEG is not an indicator of relevance.

In the second experiment the tests were DBTs:

"Neither the subjects nor the experimenters knew which conditions were being performed."

Personally, I think this thread is silly, but it has been entertaining watching you and ShadyJ get all worked up.

 

[shadyJ]

In the second experiment the tests were DBTs:

"Neither the subjects nor the experimenters knew which conditions were being performed."

Personally, I think this thread is silly, but it has been entertaining watching you and ShadyJ get all worked up.

Nothing, and I mean NOTHING, gets me angrier than erroneous claims about human hearing in ultrasonic frequencies. Poverty, worldwide hunger, child abuse, genocide, slavery; I am not saying all that is not bad, but it isn't the call to action quite like arguments based on faulty studies about perception of 20 kHz+ frequencies. This situation is intolerable!

 

[everettT]

Nothing, and I mean NOTHING, gets me angrier than erroneous claims about human hearing in ultrasonic frequencies. Poverty, worldwide hunger, child abuse, genocide, slavery; I am not saying all that is not bad, but it isn't the call to action quite like arguments based on faulty studies about perception of 20 kHz+ frequencies. This situation is intolerable!

Relax Tweek, have a cup coffee

 

[mtrycrafts]

..., but it has been entertaining watching you and ShadyJ get all worked up.

I am happy and pleased to entertain.