supposed hearing limit of 20khz is b.s., just saying

[freddemillio]

rifftrax, All I am trying to say to you is, of course you can hear 25khz at that volume. 116 DB!!! Try that at 1khz and your ears will not like it for very long. Or white noise. The reason the volume is so high, is because there is damping and less mechanical coupling at the cilia. I'm sure you could figure a roll off slope by trying the same thing the guys that made the Equal Loudness Contour did, and use your perception to judge the loudness of different tones. Would it matter in a musical context?

I would imagine that at 116 dB, all sorts of ear and general head parts start rattling around at sub-resonant frequencies and start triggering the sense of hearing.

I believe most occupational safety agencies would consider the safe exposure time to 116 dB of sound to be in the area of 30 seconds or less. I would guess that if someone was directly hearing the 25 kHz tone at 116 dB, after long exposure to this (long as compared to the safety limits), they probably would not be hearing it directly anymore as the ear structure would have been irreparably damaged.

[IncarnateX]

Still won't technically "prove" anything to a typical naysayer.

At KVR not even proof would prove anything to a naysayer, so what is really your point by posting in the first place?

[ermi]

I would just like to encourage OP to continue posting his research, with a moderate tone. Perhaps KVR is not ideal for this type of discussion, since it's more music oriented, but surely on hydrogenaudio it will be appreciated.

I think that even if (!) we were to find out 25k played back gets "reduced" to some lower freq first (by the ear canal or whatever), before being actually heard, producing 25k could still potentially affect the final outcome and could at least in theory contribute to a more pristine music reproduction.
My guess is that it would be still hard or even impossible to ABX regular musical content* with frequencies above 20k against content without them, but it's at least an interesting hypothetical scenario.


*who says test tones aren't music?

[Meffy]

Excellent. Progress! Excelsior! Testing, measurements, that's where the fulfilling fun is.

LOL, I already have all the actual data. Question is are people going to believe me when I post the spectrograms and say "you see that line? That's the sound I'm hearing". Still won't technically "prove" anything to a typical naysayer.

Then design tests and measurements in such a way that someone else won't be able to poke holes in them. That's how science works. If someone can show that your procedures or your data have flaws, you haven't got proof.

Science also doesn't work by starting with a conclusion and designing tests that you hope will prove it's true; it works by starting with a hypothesis and designing tests that determine whether it's true or false. How much you want to believe the conclusion you like is irrelevant and should not be considered.

To the extent that your tests are designed to prove your pre-accepted conclusion right rather than to determine the facts regardless of where the chips may fall, you will find others unwilling to accept them.

[edit] This isn't paranormal stuff, but I still recommend asking on the JREF (James Randi Educational Foundation) forums how to set up and conduct tests. You'll find experienced scientists and amateurs who understand the scientific method, who are used to spotting flaws in procedures and weeding out self-fulfilling prophecies. With their help you can probably get some serious, demonstrably valid research done.

[A_SN]

lol, I read the whole thread because I love the elephant in the room that is OP's confrontational and polarising style, from the very first post. The first post and even the thread title have a certain conspiracy theorist/Donald Trumpesque quality that is quite funny to read. To me the first post reads like "Hey guys check this out, science is wrong, everything you know is a lie, kay, that's some bullshit right here, cause I did a test in my office and everybody even old ass chicks can hear ultrasounds that scientists say we can't hear, we've been lied to or something, kay, like, I should write a paper about it cause the scientists who wrote papers about it before are too damn dumb to sort this shit out themselves nahahmeen?".

I mean check out these nuggets:

Myth = BUSTED

"audiologists" know f**k-all lol

what you've been taught is wrong

After the last one I was kind of expecting a theory involving the Illuminati

Not to mention the whole part where he dismisses entirely well established methods of testing as simply being "bullshit". Then he wonders why so many people in this thread are somewhat mildly antagonistic. That's the tone you set, OP. Nothing inherently wrong with the claims made, the way they were presented is pretty counter-productive. It would be better to just present what you tried and think and to ask people what they think about that. Making claims such as '"audiologists" know f**k-all' is just asking for trouble.

Why 116 dB though? If it's way loud enough at 116 dB why not try a more reasonable level like 90 dB? It actually would be quite interesting to see how low you and your co-workers can hear it.

[whyterabbyt]

what you've been taught is wrong

After the last one I was kind of expecting a theory involving the Illuminati

You do know the Illumanti beam their secret control messages to us at 23KHz, dont you? That's why 'the scientists' tell us we cant hear that high. Fnord.

[trimph1]

what you've been taught is wrong

After the last one I was kind of expecting a theory involving the Illuminati

You do know the Illumanti beam their secret control messages to us at 23KHz, dont you? That's why 'the scientists' tell us we cant hear that high. Fnord.

Snid.

[UltraJv]

As expected, hes backing out and saying that hes shown us all the data. Like I said nothing to see here...

[rifftrax]

To the extent that your tests are designed to prove your pre-accepted conclusion right rather than to determine the facts regardless of where the chips may fall, you will find others unwilling to accept them.

Woah woah woah. Hold on. Pre-accepted? First I need to cement something down here for everyone. I have already done the tests. I know the results. It's not like I'm some scientist going into a testing procedure with an inherent bias of "I want the outcome to be this because it's what I've always assumed was true blah blah blah". I want to make it very clear that after a full year of studying this stuff very intently I came to a specific set of conclusions based wholly on the research that I've been doing day in and day out.

This is not me with some axe to grind trying to corroborate as much evidence as I can to support some wild "theory" I have. I already explained that I KNOW what the outcome is. At this point all I'll be doing is posting the information so everyone can pick it up. That's it. That's all I'll be doing. I might make an additional sensitivity chart which plots out a sort of nominal ultrasonic hearing curve but that's really where the additional actual data collection and testing ends for this purpose. If you think I "designed" tests to "support" my "theory" then you haven't read all my posts.

To be honest I knew very little about ultrasonic sound in general before starting the current job I have about a year ago. I had no "god wouldn't it be awesome if I could prove everything I've ever thought about human ultrasonic hearing by working here...!!" kind of thought process. None. I just started doing testing. Seriously. That's all it amounted to here. I'm now describing my results and findings. Very basic stuff. No subterfuges. No ulterior motive. No 'hidden agenda' and all that B.S. Preeeeetty straight-forward actually.

rifftrax, All I am trying to say to you is, of course you can hear 25khz at that volume. 116 DB!!! Try that at 1khz and your ears will not like it for very long. Or white noise. The reason the volume is so high, is because there is damping and less mechanical coupling at the cilia.

Not true, it's because a human's tympanic membrane has too much mass to even respond to low pressure level sound at that frequency. The cilia are (of course) the lowest mass portion of the entire auditory system, they have to be. The limiting factor certainly does not come down to that. Even the middle ear structure will limit higher frequency sound more significantly (due to higher mass) than the inner ear.

I'm sure you could figure a roll off slope by trying the same thing the guys that made the Equal Loudness Contour did, and use your perception to judge the loudness of different tones. Would it matter in a musical context?

Apparently it does, the white paper by Tsutomu Ōhashi contained extremely detailed tests involving playback of recorded gamelan music with and without 20khz+ content which showed additional enjoyment (measured by increased brain activity in particular areas) which correlated to the participants own "rated" subjective measurements of their feelings about what they heard and how enjoyable it was to listen to.

So, yes. I believe it does. Unless you want to refute his white paper.

And on harmonics, metallic tweeters generate all kinds of ultrasound via non-linearity. It's not as appearent because it's not boosting, it's natural.

My monitors use ribbons, and plenty others use silk domes that are rated out to 30khz or beyond. Also I bet I could test my JBL 4410's with ultrasonic sine tones and find very little if any additional harmonic distortion at all (those are titanium diaphragms). I don't know why you would assume a metal diaphragm would suffer from higher distortion modes than any other tweeter material. Anyway.

I would imagine that at 116 dB, all sorts of ear and general head parts start rattling around at sub-resonant frequencies and start triggering the sense of hearing.

I'm not familiar with what you're terming "sub-resonant frequencies". You're saying that if I play a 10khz tone I can get a 5khz sympathetic resonance mode activated in a material that typical resonates at 5khz? Um. Yeah.

If you're talking about sub synchronous resonances then that only happens with mechanical interactions (like with generators) on an electrical circuit. Totally not the same thing at all.

A "sub-resonant" frequency doesn't actually even technically exist because your fundamental resonance is by definition the lowest frequency resonance of a material/etc:

http://hyperphysics.phy-astr.gsu.edu/hb ... unhar.html

I believe most occupational safety agencies would consider the safe exposure time to 116 dB of sound to be in the area of 30 seconds or less.

Completely depends on frequency actually. OSHA standards are different for ultrasonic and audible sound (which then also depends on the environment and safety precautions being taken).

I would guess that if someone was directly hearing the 25 kHz tone at 116 dB, after long exposure to this (long as compared to the safety limits), they probably would not be hearing it directly anymore as the ear structure would have been irreparably damaged.

I'm sure, which I why I don't sit there with the devices and torture my ears like that. Of course.

At KVR not even proof would prove anything to a naysayer, so what is really your point by posting in the first place?

Good point. I've been here long enough to see it play out this way first hand plenty of times.

As expected, hes backing out and saying that hes shown us all the data. Like I said nothing to see here...

No. Actually, you're not reading. Go back and read my posts. I was busy as hell yesterday and I'm going back into work next week to figure out a way to export the spectrograms to post them here. OK? OK. Yeesh.

[trimph1]

You still have not shown your data. What size of sample did you use here? What kind of hypothesis were you testing? All I see here are assertions that all audiologists lie.

I want to see the 'proof' as it were. Not assertions.

Oh well..back to the anti-aliasing....

[rifftrax]

You still have not shown your data. What size of sample did you use here? What kind of hypothesis were you testing? All I see here are assertions that all audiologists lie.

I want to see the 'proof' as it were. Not assertions.

Oh well..back to the anti-aliasing....

See above. The last response in my last post. I'm not going to go into work on my days off just to pander to KVR's inability to hold their horses and wait for a second.

lol, I read the whole thread because I love the elephant in the room that is OP's confrontational and polarising style, from the very first post. The first post and even the thread title have a certain conspiracy theorist/Donald Trumpesque quality that is quite funny to read.

Well, now we've got a decent size thread where it seems people are actually interested in knowing more. I would say that the approach worked to garner enough interest for me to feel it's worth throwing up the actual spectrograms I was working from

To me the first post reads like "Hey guys check this out, science is wrong, everything you know is a lie, kay, that's some bullshit right here, cause I did a test in my office and everybody even old ass chicks can hear ultrasounds that scientists say we can't hear, we've been lied to or something, kay, like, I should write a paper about it cause the scientists who wrote papers about it before are too damn dumb to sort this shit out themselves nahahmeen?"

Well, when you have the experience talking to person after person after person who assumes that 20khz is the "limit" of human hearing and look at tons of "positing" online that anyone can only ever hear up to 20khz then, yeah it certainly does appear to me that people have been fed some generic B.S. that was super easy to regurgitate and is now 100x harder a 'myth' to kill. Did I mention how many producers/audio engineers I've talked to who 'assume' exactly the way I'm describing that school of thought goes? I'm pretty sure I mentioned it at some point. A shit-load of people recoil when you tell them you can hear a tone @ 25khz - As we've seen so conveniently here in this thread.

The back-lash in this thread really says it all. I shouldn't even need to point it out.

I mean check out these nuggets:

Myth = BUSTED

"audiologists" know f**k-all lol

what you've been taught is wrong

After the last one I was kind of expecting a theory involving the Illuminati

I'm sorry, you'd prefer some banal boring language like "my findings suggest that certain things people have described about human hearing limitations have been greatly overestimated and needlessly bolstered"?

Not to mention the whole part where he dismisses entirely well established methods of testing as simply being "bullshit".

I called out a specific frontal testing method as totally inadequate (I would say "totally inadequate" is pretty synonymous for "bullshit" actually). I hardly think calling a single audiology testing method useless means I've single-handedly attacked all of the "established methods of testing" (remember to say that in your best snooty 'I'm-an-expert-in-my-field' voice). May I say that I love how your style is rife with aggrandized attempts to undermine my general point. Bravo.

Then he wonders why so many people in this thread are somewhat mildly antagonistic.

"Somewhat mildly antagonistic". Awesome. I don't wonder about that. I know very well that I'm posting right here at good 'ole KVR. I know the drill.

That's the tone you set, OP. Nothing inherently wrong with the claims made, the way they were presented is pretty counter-productive. It would be better to just present what you tried and think and to ask people what they think about that. Making claims such as '"audiologists" know f**k-all' is just asking for trouble.

I'll agree that was definitely too much. Fair assessment.

Why 116 dB though? If it's way loud enough at 116 dB why not try a more reasonable level like 90 dB? It actually would be quite interesting to see how low you and your co-workers can hear it.

That's the plan.

[dreamkeeper]

I want to make it very clear that after a full year of studying this stuff very intently I came to a specific set of conclusions based wholly on the research that I've been doing day in and day out.

And after all this "research", all you can come up with is (paraphrased): "All the folks in my office could hear a 25kHz tone by blasting it with 116dB at a certain angle into their ear"? Right. Very scientific!

[rifftrax]

And after all this "research", all you can come up with is (paraphrased): "All the folks in my office could hear a 25kHz tone by blasting it with 116dB at a certain angle into their ear"? Right. Very scientific!

Would you prefer I put some fancy acronyms and extra fanfare with bright ribbons and pastel balloons in there? Maybe a pull my report out from a nice attache' case in front of the judgement panel?

Honestly. You have a problem because I put my findings in a one-sentence summary readable by the general public? Wow, ok boss. Maybe if I served my findings with coffee and doughnuts I'd get a more positive response.

[dreamkeeper]

You surely have an "interesting" point of view about what 'scientific' means. No coffee and doughnuts required - some real data will suffice, thanks.

[trimph1]

And after all this "research", all you can come up with is (paraphrased): "All the folks in my office could hear a 25kHz tone by blasting it with 116dB at a certain angle into their ear"? Right. Very scientific!

Would you prefer I put some fancy acronyms and extra fanfare with bright ribbons and pastel balloons in there? Maybe a pull my report out from a nice attache' case in front of the judgement panel?

Honestly. You have a problem because I put my findings in a one-sentence summary readable by the general public? Wow, ok boss. Maybe if I served my findings with coffee and doughnuts I'd get a more positive response.

not quite.

If you go around making general assertions that 'all audiologists hold to the 20Hz to 20kHz dogma' don't be surprised at the kind of response you will get. Meffy has suggested some good resources that can be used to test the scenario you are proposing here. All I perceive from this thread is that you really have no idea what science actually involves...