Not necessarily. General case can get quite complex and would depend. However, this can be sometimes be interesting in practice: IMD Measurement with 19 kHz and 20 kHz Tones - Audio Precision
No doubt you have seen the plots for particular amps. Sometimes quite a bit is seen at lower frequencies. But, it depends, I think we could agree. Also, probably a reason people mention cymbals as something that can be revealing of certain distortion problems. They can produce a lot of high level HF.
No doubt you have seen the plots for particular amps. Sometimes quite a bit is seen at lower frequencies. But, it depends, I think we could agree. Also, probably a reason people mention cymbals as something that can be revealing of certain distortion problems. They can produce a lot of high level HF.
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Hi Bimo,
After reading that paper for that study, I didn't see anywhere where it was claimed people could hear those frequencies. Sensing them is an entirely different mechanism and I also noted that the power levels had to be increased a fair amount to generate clear results.
So no. You cannot directly hear those frequencies at normal listening levels.
-Chris
After reading that paper for that study, I didn't see anywhere where it was claimed people could hear those frequencies. Sensing them is an entirely different mechanism and I also noted that the power levels had to be increased a fair amount to generate clear results.
So no. You cannot directly hear those frequencies at normal listening levels.
-Chris
I'm not interested in the general case. I been talking about the specific case of high NFB at lower frequencies, but with 40-60dB less at 20kHz. I can't see this as actually being a bad thing and in this case it holds the IM distortion in the audio band WILL be supressed by the NFB. By inference I'm struggling to understand the advantage of having increased NFB at 20kHz and no one has come up with a good reason other than claiming they can hear ultrasonics.
20kHz may be arbitrary. Again, where people commonly notice problems is with cymbals. They tend to produce a lot of harmonically unrelated frequencies over a fairly broad bandwidth. Some of it extends into rather high frequencies maybe at 20kHz or higher. Wherever in the frequency spectrum the problem arises cymbals seem to be one of the first things audibly affected.
Don't know about anyone else, but I like my cymbal reproduction to be as undistorted as possible. I would suspect a good deal of what people do hear could well be related to falling loop gain and increased IMD up where some cymbal frequencies reside. Whether 15kHz or 18kHz is a better number to look at as compared to 20kHz for test purposes I don't know.
I would agree that people are probably not directly hearing normal level ultrasonics. Sean Olive seems to think some youngsters might be able to hear up as high as 30kHz, at least that was a number he once said as being a possibility, but not for adults.
Don't know about anyone else, but I like my cymbal reproduction to be as undistorted as possible. I would suspect a good deal of what people do hear could well be related to falling loop gain and increased IMD up where some cymbal frequencies reside. Whether 15kHz or 18kHz is a better number to look at as compared to 20kHz for test purposes I don't know.
I would agree that people are probably not directly hearing normal level ultrasonics. Sean Olive seems to think some youngsters might be able to hear up as high as 30kHz, at least that was a number he once said as being a possibility, but not for adults.
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Suggest go to a music store and listen to some cymbals. They sound different and distinct depending on how they are made and how they are struck. Then go home and listen on the stereo. On many stereos they sound a lot like you describe, almost like noise bursts. To me that would indicate a problem somewhere.
As I wrote, very very few papers over a long time doesn't bode well for it being verifiable. At this point it might be true. It might also be something to do with their setup and what they're actually testing isn't what they're thinking they're testing. Might it have been a form of modulation through their test setup? Similarly, external EEG is very noisy, so subtle signals are hard to discern. This kind of stuff happens all the time, which is why multiple researchers with different approaches is important to verify something. Or for the really big experiments, lots of people picking it apart (plus huge huge huge positive predictive value). See for example the interconnect timing correction error that had LHC and the partner neutrino site in northern Italy (iirc!) measuring supraluminal particles for a bit. (They weren't)
I've recently been able to discern 17khz on some of the online tests on my laptop (late night curiosity, can't remember which one but it used a ABX protocol), but that could be from aliasing or other garbage on the cheap sound card just as much as anything. Nor do I claim to have that great of ability to discern a sixth of what some folks claim. (Take that in any way you will, I take it in a mix of my own lack of training and incredible claims by others--edit, no this is not aimed at anyone in specific)
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I had to do a lot of research on U/S safety because we use it in production.
At that level, I am not comfortable. You are a talking several hundred acoustic watts off the shelf.
I suspect that when the initial work was being done, Google scholar wasn't around. I found significant information on problems associated with high U/S exposure in the workplace. However, the upper limit info I found was 60kHz, and that was for measurement of the eyes to brain transfer function.
At that energy density, I would be concerned with cataracts; I note that I've not seen any data regarding that. However, I suspect no testing was done as that would not be allowed.
Jn
Yes, I am Batty! but that is beside the point. hearing cut off is not a brick wall. Also it is a bell curve. There are people who can hear very well beyond 20 khz.
I presume cymbals are very difficult to mic, mix and reproduce accurately, you'd know better than me. My point is that they are such a wideband source, with the majority of their output in the 300 to 3k range, as I understand it, that IMD would be very hard to discern?
I can sense Ultrasonic sound despite my pathological HF ear response. It drives me nuts.
I am also allergic to harsh HF response on music reproduction.
By coincidence, hypersensitivity to HF sound reproduction aberrations is a documented symptom on people with problematic hearing.
George
If it sounds different on the stereo than at the music store there are only so many things that could account for the difference. They might be classified as added noise, nonlinear distortion, and linear distortion. Where they occur in the signal chain could be measured to some extent. As a test one could record the mic output and every output after that in the signal chain to see where and how much the signal changes. If it doesn't change much at all that might suggest a problem at the mic. Is that the type of thing you are talking about?
Or maybe you just mean hard to discern by listening?
I don't know. I guess some people might say they find it hard to believe in General Relativity, or something. Belief is a funny thing and it usually seems to work best when people can do an experiment for themselves. Why don't you try going to a well equipped music store and listen to some cymbals. Hold the stick loosely and hit them lightly with a wood-tipped stick in different places. There are some that are really ideal for that because they are designed to be very versatile and I would recommend trying these if possible: Zildjian K Custom Hybrid Cymbal Box Set - 14" HiHats, 17" Crash, 21" Ride | Sweetwater (By the way, that is a terrific price on the set if you know a drummer who likes that kind)
If you listen to them for awhile and see for yourself the wide variety of distinct sounds they produce then go home and listen to whatever recording you want that might have clean cymbals and just see for yourself. I think your doubts will dissolve pretty instantly. If not, I would certainly be interested to hear what you might have to say on that.
EDIT: If you have trouble hearing then maybe you could take someone with you that you trust to help out with the experiment? Not sure, I thought you may have said there was some issue at some point in the past, IIRC. Or, maybe I mis-remember, could be.
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I linked to hyperacusis and recruitment not long ago, but I think it fell on “deaf ears” ;-)
https://www.deafhear.ie/DHFiles/docs/Hyperacusis, Recruitment and Loudness Discomfort.pdf
It’s known that hyperacusis (changes in perceived loudness) is frequently found in those with hearing loss / recruitment. However, one doesn’t require the other. It doesn’t seem to be fully understood.
But it does seem relatively common and not just in the very old or very hard of hearing.
That to me would indicate it’s worth seriously exploring that what may “sound right” to a trained audio professional changes as they age despite the sound emanating from the loudspeaker remaining the same.
This could explain these small differences in taste much more easily than “golden ears”..... In other words, it’s not across the board precision but pronounced dumps and dips in certain areas that’s actually related to a problem, not a super power.
Of course device measurements and designer skill are relevant, but many in the high end tune by ear.
However, no one seems to want to go there... for reasons I’d have to assume are ego driven? Or maybe I’m just on everyone’s ignore list by now!
https://www.deafhear.ie/DHFiles/docs/Hyperacusis, Recruitment and Loudness Discomfort.pdf
It’s known that hyperacusis (changes in perceived loudness) is frequently found in those with hearing loss / recruitment. However, one doesn’t require the other. It doesn’t seem to be fully understood.
But it does seem relatively common and not just in the very old or very hard of hearing.
That to me would indicate it’s worth seriously exploring that what may “sound right” to a trained audio professional changes as they age despite the sound emanating from the loudspeaker remaining the same.
This could explain these small differences in taste much more easily than “golden ears”..... In other words, it’s not across the board precision but pronounced dumps and dips in certain areas that’s actually related to a problem, not a super power.
Of course device measurements and designer skill are relevant, but many in the high end tune by ear.
However, no one seems to want to go there... for reasons I’d have to assume are ego driven? Or maybe I’m just on everyone’s ignore list by now!
From the article:
“Continuous and loud noise is a source of irritation to most people. However, some people have especially sensitive ears and are unable to tolerate ordinary levels of noise. Although this does occur in people with normal hearing, recruitment or loudness discomfort is more commonly associated with a hearing loss.
A situation familiar to many will be the response, often of an older person, having difficulty in hearing what you say, “Speak up a bit, I can’t hear what you’re saying” and then “Don’t shout! I’m not deaf”.
In this situation, hearing becomes impaired, usually due to the loss of tiny hair cells in the inner ear, and most commonly for the high frequency sounds (bird call, telephone bells etc.) Because the overall population of hair cells and nerve endings responsible for picking up sound in the inner ear is reduced, the ability to grade different intensities of sound is also impaired.
This means that as the intensity of sound increases above the threshold of hearing, it very rapidly ‘switches on’ (or ‘recruits’) all remaining nerve fibres running from the cochlea, producing a sensation of near maximum loudness. Therefore, even in an ear in which there is hearing impairment, quite moderate intensities of sound in the environment may seem to be unbearably loud.
A normal ear is able not only to hear extremely quiet sounds (between 0 and 20dB hearing level) but can also tolerate very loud sound without discomfort (up to levels of 110dB hearing level). An ear with recruitment might well be unable to hear sounds, particularly high frequency sounds, below 50dB, but find any sounds above 80dB not only uncomfortable but liable to produce distortion.”
“Continuous and loud noise is a source of irritation to most people. However, some people have especially sensitive ears and are unable to tolerate ordinary levels of noise. Although this does occur in people with normal hearing, recruitment or loudness discomfort is more commonly associated with a hearing loss.
A situation familiar to many will be the response, often of an older person, having difficulty in hearing what you say, “Speak up a bit, I can’t hear what you’re saying” and then “Don’t shout! I’m not deaf”.
In this situation, hearing becomes impaired, usually due to the loss of tiny hair cells in the inner ear, and most commonly for the high frequency sounds (bird call, telephone bells etc.) Because the overall population of hair cells and nerve endings responsible for picking up sound in the inner ear is reduced, the ability to grade different intensities of sound is also impaired.
This means that as the intensity of sound increases above the threshold of hearing, it very rapidly ‘switches on’ (or ‘recruits’) all remaining nerve fibres running from the cochlea, producing a sensation of near maximum loudness. Therefore, even in an ear in which there is hearing impairment, quite moderate intensities of sound in the environment may seem to be unbearably loud.
A normal ear is able not only to hear extremely quiet sounds (between 0 and 20dB hearing level) but can also tolerate very loud sound without discomfort (up to levels of 110dB hearing level). An ear with recruitment might well be unable to hear sounds, particularly high frequency sounds, below 50dB, but find any sounds above 80dB not only uncomfortable but liable to produce distortion.”
Mechanism please. That's all I am asking. Not suspicion, mechanism. Or its another case of belief over-riding everything else.
I have tinnitus and some high frequency hearing loss. I think I understand what you are saying, but attributing the difference to IMD seems like a bit of a stretch to me, unless I'm misunderstanding you, which is entirely possible
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