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Launch of Pono Studio Headphones
Old 25th March 2014
  #1741
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nuthinupmysleeve's Avatar
 

Quote:
Originally Posted by jkorten View Post
Remember all those amplifier reviews where the reviewer shows the 10kHz square wave response? With CDs you don't even have to worry about them. With 192kHz you see and hear that it is a square wave once more.
What makes a square wave a square wave is the existence of harmonics above 20k.

It's true those harmonics don't exist in 44.1, so it's true the higher frequency square waves don't exist in 44.1.. as it gets closer to 20k it can only be a sine wave.

However, you assume you can hear the lack of those harmonics... that you are missing them. Or said differently... you assume if you play back that analog generated 10k square wave it will sound different than what you hear coming out of a digital audio file that doesn't LOOK like a square wave.

I'm not saying you can't hear the difference.. I am saying don't assume you CAN just because the waveform LOOKS different. We are testing hearing, not seeing.
Old 25th March 2014
  #1742
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Kenny Gioia's Avatar
 

Quote:
Originally Posted by CarmenC View Post
For all those who dismiss anything but science, a timely article...
I'm sorry.

This might be the funniest thing I've ever read on GS.

Or the internet even.

Quote:

sci·ence
?s??ns/
noun

the intellectual and practical activity encompassing the systematic study of the structure and behavior of the physical and natural world through observation and experiment.
Why would anything besides the definition I posted, even matter?

Are you against observation?

Are you against experiments?

IMHO - the only things that exist beyond science are religion, magic and ignorance.
Old 25th March 2014
  #1743
Quote:
Originally Posted by jkorten View Post
You are not the only one. Here is a picture of a 10kHz square wave from my signal generator, digitized at 44.1kHz on a professional ADC and played back on a professional DAC to my oscilloscope (OK that scope WAS professional in 1988 or so).

Attachment 391230


Here is the original waveform


Attachment 391232

Remember all those amplifier reviews where the reviewer shows the 10kHz square wave response? With CDs you don't even have to worry about them. With 192kHz you see and hear that it is a square wave once more.
You fed in a square wave and your ADC/DAC turned it into a nice sine wave. Man, that's awesome. Broken as hell (assuming the situation is as described) but awesome.

Contrary to your last paragraph, you will NOT get a true square wave at 192 kHz SR. You can't have a true square wave without infinite frequency bandwidth. But with higher SR's you, naturally enough (if one understands the basics which clearly many here do not), get faster signal ballistics, leading to a faster rise time and something 'closer' to the true vertical, instantaneous transitions of a true square wave (which still do not exist, even in analog circuits, because there IS no such thing in the real world as infinite frequency b/w.) That said, our ears do not have infinite frequency b/w either and, so, a near-square wave that represents frequency b/w above our own particular hearing perceptual boundaries will sound to us the same as near-square waves with much higher frequency b/w. Once our transcription media exceeds our own hearing b/w, we can't hear differences resulting from that enhanced media b/w -- assuming a properly functioning system, of course. As always, only math is perfect. The particular pretty much always diverges from the ideal (above the molecular level, anyhow).
Old 25th March 2014
  #1744
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fwiw a certain mixerman is a huge fan of that tape op article (check his facebook). For me an ABX is still an ABX but.... I'm no mixerman.
Old 25th March 2014
  #1745
Gear Nut
 

Quote:
Originally Posted by nuthinupmysleeve View Post
What makes a square wave a square wave is the existence of harmonics above 20k.

It's true those harmonics don't exist in 44.1, so it's true the higher frequency square waves don't exist in 44.1.. as it gets closer to 20k it can only be a sine wave.

However, you assume you can hear the lack of those harmonics... that you are missing them. Or said differently... you assume if you play back that analog generated 10k square wave it will sound different than what you hear coming out of a digital audio file that doesn't LOOK like a square wave.

I'm not saying you can't hear the difference.. I am saying don't assume you CAN just because the waveform LOOKS different. We are testing hearing, not seeing.
You are simplifying the situation grossly. I will leave alone the fact that I can easily hear the difference between a sinewave and a squarewave at 10kHz. If you can't you are lucky - go to best buy and purchase an inexpensive stereo and speakers. Alas I am not so lucky.

But check this out - this is a 2.5kHz square wave recorded at 44.1kHz and look at that ringing on it! The magnitude is a lot more than -20db to the fundamental. The period of this ringing is ~21kHz - you know why? Because of the digital filtering done during sampling AND AGAIN during playback! This fixed ringing is occuring everywhere in a complex signal and if you are trying to listen to the beautiful sound of massed strings playing - and you superimpose a fixed 21kHz signal on that - you end up with a hash sound that gives you a headache.


Launch of Pono-2.5khz_dac_playback.jpg



There are many problems with a low sample rate and you folks who cling to 44.1kHz are really just barking up the wrong tree here. There are many benefits to using a higher sample rate.
Old 25th March 2014
  #1746
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Arksun's Avatar
Quote:
Originally Posted by auralart View Post
**** I must be the only one on GS that hears a difference in higher sample rates. I don't know or care about the whole science of mechanics of it, but the difference to me is that the higher you go the more it feels like the music is "in the room" with you. Maybe I subconsciously bought into the hype. Meh whatever, I like the higher sample rates and always thought the projects I did in 96 were more pleasing than the ones in 44.1
It wouldn't be at all surprising if you hear a clear audible difference between working on a project in a DAW at 96k vs 44k if it uses a lot of plugins, as its a well known fact that some plugins perform differently at different sample rates (most obvious difference being when there is more aliasing introduced at lower sample rate)

But that is an entirely seperate discussion from whether 44khz is a high enough sample rate for the final medium for consumers to hear. To gauge a sense of that, instead of comparing a 96k DAW project vs 44K DAW project. Render your 96k project to a stereo wave file, then use a high quality sample rate converter (not the one built into the DAW they tend to be fairly poor) to convert that down to 44k, that will give a far better idea of the differences being discussed in this thread
Old 25th March 2014
  #1747
Gear Nut
 

Quote:
Originally Posted by theblue1 View Post
You fed in a square wave and your ADC/DAC turned it into a nice sine wave. Man, that's awesome. Broken as hell (assuming the situation is as described) but awesome.

Contrary to your last paragraph, you will NOT get a true square wave at 192 kHz SR. You can't have a true square wave without infinite frequency bandwidth. But with higher SR's you, naturally enough (if one understands the basics which clearly many here do not), get faster signal ballistics, leading to a faster rise time and something 'closer' to the true vertical, instantaneous transitions of a true square wave (which still do not exist, even in analog circuits, because there IS no such thing in the real world as infinite frequency b/w.) That said, our ears do not have infinite frequency b/w either and, so, a near-square wave that represents frequency b/w above our own particular hearing perceptual boundaries will sound to us the same as near-square waves with much higher frequency b/w. Once our transcription media exceeds our own hearing b/w, we can't hear differences resulting from that enhanced media b/w -- assuming a properly functioning system, of course. As always, only math is perfect. The particular pretty much always diverges from the ideal (above the molecular level, anyhow).
I'm not sure what you are saying here. I didn't manage to turn a square wave into a sine wave, the filtering required during analog to digital, and then again during digital to analog conversion are required in order not to let through frequencies that are aliased. This is a result of what is built in to the equipment. Nothing that I "did" to the waveform.

Of course you don't get a "true square wave" you get something that looks exactly like the 2.5kHz sinewave sampled at 44.1kHz I just posted above.

Nobody says you have to have infinite bandwidth. But that doesn't mean you need no bandwidth. So I'm not sure what you are trying to argue. I do agree with your last statement - that once we transcribe with a b/w that matches or exceeds ours - it would probably be good enough!

For instance - in the case of the ringing on the 10kHz square wave sampled at 192kHz it would be somewhere near 90kHz and would be ultrasonic and we probably wouldn't notice it (well except for bats maybe and I doubt that).
Old 25th March 2014
  #1748
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Arksun's Avatar
Quote:
Originally Posted by jkorten View Post
But check this out - this is a 2.5kHz square wave recorded at 44.1kHz and look at that ringing on it! The magnitude is a lot more than -20db to the fundamental. The period of this ringing is ~21kHz - you know why? Because of the digital filtering done during sampling AND AGAIN during playback! This fixed ringing is occuring everywhere in a complex signal and if you are trying to listen to the beautiful sound of massed strings playing - and you superimpose a fixed 21kHz signal on that - you end up with a hash sound that gives you a headache.
I think you need to watch the last section of the Digital Show and Tell youtube video that explains this very clearly. Try to think of all sounds as fundamentals and harmonics, what you're seeing there is a fundamental and odd harmonics up to half the sampling rate (ie up to the upper limits of human hearing), what you're describing as ringing artifacts are in fact those very harmonics!. If you were to keep increasing the harmonics higher and higher up to infinity, it would start looking a lot more like a square shaped wave on the screen. Does it matter that it doesn't look like a perfect square wave?, no, well not unless you believe we can actually hear up to a far higher frequency than 20khz.

So what you're seeing on the oscilloscope is completely normal behaviour and nothing to worry about really.
Old 25th March 2014
  #1749
Quote:
Originally Posted by jkorten View Post
You are simplifying the situation grossly. I will leave alone the fact that I can easily hear the difference between a sinewave and a squarewave at 10kHz. If you can't you are lucky - go to best buy and purchase an inexpensive stereo and speakers. Alas I am not so lucky.

But check this out - this is a 2.5kHz square wave recorded at 44.1kHz and look at that ringing on it! The magnitude is a lot more than -20db to the fundamental. The period of this ringing is ~21kHz - you know why? Because of the digital filtering done during sampling AND AGAIN during playback! This fixed ringing is occuring everywhere in a complex signal and if you are trying to listen to the beautiful sound of massed strings playing - and you superimpose a fixed 21kHz signal on that - you end up with a hash sound that gives you a headache.


Attachment 391235



There are many problems with a low sample rate and you folks who cling to 44.1kHz are really just barking up the wrong tree here. There are many benefits to using a higher sample rate.
You are misinterpreting well-understood products of the Gibbs Phenomenon, which, crudely put, results when Fourier transforms are applied to discontinuous signals like square waves.

Gibbs phenomenon - Wikipedia, the free encyclopedia

As Arksun notes, the Xiph/Monty Montgomery vid does a fairly nice job of giving a simplified explanation of the Gibbs phenomenon as well as discussing its implications.
Old 25th March 2014
  #1750
Gear Nut
 

Quote:
Originally Posted by theblue1 View Post
You are misinterpreting well-understood products of the Gibbs Phenomenon, which, crudely put, results when Fourier transforms are applied to discontinuous signals like square waves.

Gibbs phenomenon - Wikipedia, the free encyclopedia

As Arksun notes, the Xiph/Monty Montgomery vid does a fairly nice job of giving a simplified explanation of the Gibbs phenomenon as well as discussing its implications.

You guys are so very wrong. There is no fourier transform going on when we digitize a waveform.

This is the result of the convolution of the digital filter kernel (usually diplayed as the "impulse response" of a DAC) and the signal.

There is NO FREQUENCY TRANSFORMATION occuring here. Sorry guys. This is pure and simple digital filtering artifact.

If you aware of an analog to digital converter, or a digital to analog converter that is performing time domain to frequency domain conversion and back again to generate a signal - stay away from it. It will bring you no joy.
Old 25th March 2014
  #1751
Quote:
You guys are so very wrong. There is no fourier transform going on when we digitize a waveform.
LOFL

Damn, this place gets funnier and funnier.
Old 25th March 2014
  #1752
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Quote:
Originally Posted by Kenny Gioia View Post
I'm sorry.

This might be the funniest thing I've ever read on GS.

Or the internet even.



Why would anything besides the definition I posted, even matter?

Are you against observation?

Are you against experiments?

IMHO - the only things that exist beyond science are religion, magic and ignorance.
Did you read it?
Old 25th March 2014
  #1753
Gear Guru
 

Quote:
Originally Posted by nuthinupmysleeve View Post
I'm not saying you can't hear the difference.. I am saying don't assume you CAN just because the waveform LOOKS different. We are testing hearing, not seeing.
this guy flips between sine and square at different frequencies. Unsurprisingly, the differences disappear as you go higher. The 'missing overtones' become inaudible precisely where your hearing leaves off. In other words, it's all sine waves.

If people don't trust the YouTube audio, that's perfectly reasonable, but it is so easy to run this test for yourself as well.

Old 25th March 2014
  #1754
Gear Nut
 

Quote:
Originally Posted by joeq View Post
this guy flips between sine and square at different frequencies. Unsurprisingly, the differences disappear as you go higher. The 'missing overtones' become inaudible precisely where your hearing leaves off. In other words, it's all sine waves.

If people don't trust the YouTube audio, that's perfectly reasonable, but it is so easy to run this test for yourself as well.

Rubbish to do this on a computer. You have no idea what digital filtering is occurring in your computer's codecs.

The only way you can discern where your own threshold is, is to hook up a signal generator to a speaker, switch between sine and square at successively higher frequencies, until you hear no more difference. You can then safely infer your preferred sample rate from that experiment.
Old 25th March 2014
  #1755
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bogosort's Avatar
Quote:
Originally Posted by jkorten View Post
You are simplifying the situation grossly. I will leave alone the fact that I can easily hear the difference between a sinewave and a squarewave at 10kHz. If you can't you are lucky - go to best buy and purchase an inexpensive stereo and speakers. Alas I am not so lucky.
It is you who are grossly oversimplifying. The second harmonic (first overtone) of a 10 kHz square wave is at 30 kHz. Are you seriously claiming in public that you can hear a 30 kHz harmonic?

Quote:
But check this out - this is a 2.5kHz square wave recorded at 44.1kHz and look at that ringing on it! The magnitude is a lot more than -20db to the fundamental. The period of this ringing is ~21kHz - you know why? Because of the digital filtering done during sampling AND AGAIN during playback! This fixed ringing is occuring everywhere in a complex signal and if you are trying to listen to the beautiful sound of massed strings playing - and you superimpose a fixed 21kHz signal on that - you end up with a hash sound that gives you a headache.
Please research the Gibbs phenomenon. What you are seeing is not filter ringing; it is the way the universe handles discontinuities. Try graphing a square wave, one sine wave at a time, and you will see that very same "ringing". You could try sampling a 2.5 kHz square wave at GHz rates and you would still see the "ringing" at the same amplitude. It is a mathematical certainty.
Old 25th March 2014
  #1756
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bogosort's Avatar
Quote:
Originally Posted by jkorten View Post
The only way you can discern where your own threshold is, is to hook up a signal generator to a speaker, switch between sine and square at successively higher frequencies, until you hear no more difference. You can then safely infer your preferred sample rate from that experiment.
This test fails at the frequency where the linearity of any part of the system stops. In other words, if your speakers are linear only to 20 kHz, you cannot use this test because what you will most likely be hearing is in-band intermodulation distortion from the nonlinearities.
Old 25th March 2014
  #1757
Gear Guru
 
Kenny Gioia's Avatar
 

Quote:
Originally Posted by GJ999x View Post
fwiw a certain mixerman is a huge fan of that tape op article (check his facebook). For me an ABX is still an ABX but.... I'm no mixerman.
Quote:
Originally Posted by CarmenC View Post
Did you read it?
I did and I have no issue with it actually. My statement was about how you phrased as if we should believe anything other than what can be proven.

Anyhoo.

The disconnect that some people seem to have is that even if you are correct. And there is some ultrasonic information that we can sense. Or that (something we all agree on) we're not capturing live audio perfectly,

WHY DO YOU ASSUME THAT 192KHZ IS SOLVING THAT PROBLEM???

You test to see if something is solving a problem. You don't assume that just because there is a problem that you've solved it just by raising a particular variable.
Old 25th March 2014
  #1758
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Quote:
Originally Posted by jkorten View Post

The only way you can discern where your own threshold is, is to hook up a signal generator to a speaker, switch between sine and square at successively higher frequencies, until you hear no more difference. You can then safely infer your preferred sample rate from that experiment.
What is the highest frequency sine wave you are able to hear?

Chris
Old 25th March 2014
  #1759
Quote:
Originally Posted by jkorten View Post
Rubbish to do this on a computer. You have no idea what digital filtering is occurring in your computer's codecs.

The only way you can discern where your own threshold is, is to hook up a signal generator to a speaker, switch between sine and square at successively higher frequencies, until you hear no more difference. You can then safely infer your preferred sample rate from that experiment.
The Xiph video demonstrates its points using analog test gear. Analog test gear, properly applied, confirms what the math tells us will happen in digital transcription.
Old 25th March 2014
  #1760
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Quote:
Originally Posted by Kenny Gioia View Post

The disconnect that some people seem to have is that even if you are correct. And there is some ultrasonic information that we can sense. Or that (something we all agree on) we're not capturing live audio perfectly,



You test to see if something is solving a problem. You don't assume that just because there is a problem that you've solved it just by raising a particular variable.
To be fair, if there was any advantage to extending the frequency bandwidth to contain ultrasonic content, a higher sampling frequency would be the way to do it.

Chris
Old 25th March 2014
  #1761
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bogosort's Avatar
Quote:
Originally Posted by Kenny Gioia View Post
You test to see if something is solving a problem. You don't assume that just because there is a problem that you've solved it just by raising a particular variable.
Of course, but marketing pushes the more is better mantra, which preys on our fallible intuition. If there were a 128-bit button on our converters, how many do you think would push it?
Old 25th March 2014
  #1762
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Quote:
When you digitize a waveform you store it's voltage at a certain point in time. You apply a low pass filter to the signal before it is digitized to prevent frequency components higher than half the sample rate from appearing in your stored waveform. This is what is generating the artifact. (And the playback filter as well.
The limits of the human auditory system also function as a low pass filter, so even if the ultrasonic content was still there and was reproduced by the speakers, the information arriving at your brain would still be subject to the same effect.

Chris
Old 25th March 2014
  #1763
Quote:
Originally Posted by joeq View Post

Where is this science you say "proves" it?
It's a study published in peer-reviewed journal; the study demonstrates the mechanisms and pathways by which ultrasound is a component of the hearing process.
Quote:
Originally Posted by joeq View Post
... The one study you linked to was not even about perception, merely transmission....
For a start I didn't introduce the study to the thread - I did link to the paper though because it does indeed demonstrate the mechanism and pathway by which ultrasound becomes a component of hearing.
Perception is a red-herring that you've repeatedly thrown in when presented with data which contradicts your position. The fact is that what constitiutes 'perception' is another discussion better-suited to another forum and certainly not something I will waste my time debating with you as you already seem to have a fixed position about that.
Quote:
Originally Posted by joeq View Post
...It, in fact, showed the opposite of what you claim...
I wrote that ultrasound is a component in hearing...where does the study show the opposite?
Quote:
Originally Posted by joeq View Post
...That even though ultrasonic vibrations were present at the inner ear, the subjects were unaware of their existence...
That doesn't mean that ultrasound isn't a component in hearing though. It is you who seem to have misinterpreted the study.
Quote:
Originally Posted by joeq View Post
...You not only did not understand the purport of the study the first time you posted it, you deliberately ignored the posts that pointed out your error and posted it again hoping to slip it by as "evidence" of ultrasonic perception.
You are making that up; throughout the thread you've consistently misrepresented others positions to support a non-existent argument. I've provided enough data to show that ultrasound is a component in hearing; it is yourself who has failed to acknowledge that and has obfuscated the debate to cover up.
Quote:
Originally Posted by joeq View Post
...There is a reason why texts, references and encyclopedias all agree on the values for the range of human hearing. That is because all the experiments studies and measurements agree...
The point you've again failed to acknowledge is that science is an ongoing and contested field of endeavour...not a rigid set of 'rules' - I don't disagree that texts/references/etc. show a given human hearing range...I've designed and taken part in similar experiments myself BUT those experiments are designed to measure sound that can be heard; those experiments are not not designed to measure the effects of sound which the subject cannot consciously perceive. The tinnitus study does that; it demonstrates that sound which the subject cannot consciously perceive does indeed have an effect on the human hearing mechanism and it clearly identifies the pathway involved.
Quote:
Originally Posted by joeq View Post
...When a lot of experiments all agree, that's a pretty good sign that your opinion is no longer relevant. ..
This is such a wrong notion...you should read up on the history of science...lots of examples of how certainty and proof have held back human understanding.
Quote:
Originally Posted by joeq View Post
The only place where there is any 'controversy' is from the audio woo-woos and they don't do any controlled studies or blind tests. While they frequently seek out or claim the imprimatur of science, they don't do "science". If they did conduct a scientific test - without cheating - they would get the same result because that's what the reality happens to be.
If that's your opinion then that is it - as I said earlier I have no desire to change your opinion.
Quote:
Originally Posted by joeq View Post
...If new studies got 'new' results, these references and encyclopedias can be literally updated in a matter of days!..
So that allows for the fact they could be incorrect...very wise.
Quote:
Originally Posted by joeq View Post
...Unlike YOU, scientists are not stubborn. They are fact-slutz. If the facts say something, they go with it. Even if they "wish" it said something else.
Believe it or not I am a scientist...a qualified scientist with a degree from an outstanding university (which is enough validation for me whatever your opinion is). I think you misunderstand and misuse science. Science isn't a shield to defend a chosen theory it is field of dreams in which the thinkers can move human understanding beyond the confines of dogma.

Earlier in the thread you accused me of having an obsession with ultrasound (amongst your other ad hominems) but from my perspective it is you who has a phobia of ultrasound or that it should play any part in human perception or hearing. The fact is that ultrasound exists - both inside our bodies/minds and the the world we inhabit.

From a limited set of studies (of which the design does not account for the effects of ultrasound) you've extrapolated that to mean that ultrasound has NO ROLE in hearing; you have your opinion but that isn't enough for me to discount ultrasound as worthy of further study.
Old 25th March 2014
  #1764
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Quote:
Originally Posted by bogosort View Post
Of course, but marketing pushes the more is better mantra, which preys on our fallible intuition. If there were a 128-bit button on our converters, how many do you think would push it?
That would have an actual noise floor advantage though...


Chris
Old 25th March 2014
  #1765
Gear Nut
 

Quote:
Originally Posted by bogosort View Post
It is you who are grossly oversimplifying. The second harmonic (first overtone) of a 10 kHz square wave is at 30 kHz. Are you seriously claiming in public that you can hear a 30 kHz harmonic?



Please research the Gibbs phenomenon. What you are seeing is not filter ringing; it is the way the universe handles discontinuities. Try graphing a square wave, one sine wave at a time, and you will see that very same "ringing". You could try sampling a 2.5 kHz square wave at GHz rates and you would still see the "ringing" at the same amplitude. It is a mathematical certainty.
A Quote from the wiki page:

"From the point of view of signal processing, the Gibbs phenomenon is the step response of a low-pass filter, and the oscillations are called ringing or ringing artifacts. Truncating the Fourier transform of a signal on the real line, or the Fourier series of a periodic signal (equivalently, a signal on the circle) corresponds to filtering out the higher frequencies by an ideal (brick-wall) low-pass/high-cut filter. This can be represented as convolution of the original signal with the impulse response of the filter (also known as the kernel), which is the sinc function. Thus the Gibbs phenomenon can be seen as the result of convolving a Heaviside step function (if periodicity is not required) or a square wave (if periodic) with a sinc function: the oscillations in the sinc function cause the ripples in the output."

Here they are explaining how the low pass filter used (convolution of filter kernel with the signal) exhibits RINGING. So I grant you - the Gibb's phenomenon can be used to explain this too - but we are not dealing with a frequency transformation in the ADC/DAC case here.

The Gibbs phenomenon EXPLAINS why the ringing is caused by the digital filtering, this is true - by example in the case stated above of a frequency transformation of both the kernel and the signal.

But the ringing has to do with the digital filter being convolved with the waveform. But this does not mean the ringing isn't due to the digital filtering required by a particular sample rate. It is.
Old 25th March 2014
  #1766
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Quote:
Originally Posted by Arthur Stone View Post
Perception is a red-herring that you've repeatedly thrown in when presented with data which contradicts your position. The fact is that what constitiutes 'perception' is another discussion better-suited to another forum and certainly not something I will waste my time debating with you as you already seem to have a fixed position about that.
I wrote that ultrasound is a component in hearing...where does the study show the opposite?
That doesn't mean that ultrasound isn't a component in hearing though. It is you who seem to have misinterpreted the study.
.
"Hearing, auditory perception, or audition is the ability to perceive sound by detecting vibrations,[1] changes in the pressure of the surrounding medium through time, through an organ such as the ear. Sound may be heard through solid, liquid, or gaseous matter.[2] It is one of the traditional five senses. The inability to hear is called deafness."

Chris
Old 25th March 2014
  #1767
Gear Nut
 

Quote:
Originally Posted by bogosort View Post
It is you who are grossly oversimplifying. The second harmonic (first overtone) of a 10 kHz square wave is at 30 kHz. Are you seriously claiming in public that you can hear a 30 kHz harmonic?
Where is it stated that you have to hear 30kHz to hear the difference between a sine wave and a square wave at 10kHz?

Just do a simple experiment and play a signal generator through your headphones or a speaker at 10kHz and switch between a square wave and a sine wave. I guarantee you will hear the difference.
Old 25th March 2014
  #1768
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bogosort's Avatar
Quote:
Originally Posted by Chris93 View Post
That would have an actual noise floor advantage though...
That's the thing: intuitively one would think so, but the reality is that we'd gain absolutely nothing except for bigger file sizes. I haven't done the arithmetic, but my hunch is that 128 bits can hold the dynamic range of the universe: from quantum interactions to the big bang. When our very best analog electronics can hardly fill 24 bits (and most has far less precision), there is clearly no point in trying to store more.
Old 25th March 2014
  #1769
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Arksun's Avatar
Quote:
Originally Posted by Arthur Stone View Post
Believe it or not I am a scientist...a qualified scientist with a degree from an outstanding university
Then as a qualified scientist, you of all people should know that study you linked to was mearly proving that direct physical contact (or extreme close range direct firing through air to the eyball) of ultrasound causes vibrations to the bone or possibly even brain, but nowhere in that study did it make a case for ultrasonic signals being actually processed by the brain in such a way the person is aware of it.

It's like arguing sticking a knife into the brain will be felt just because the act of sticking some physical into the brain tissue is possible. Surgeons perform brain surgery on live patients, when the brain is prodded, they don't feel a thing because there's no nerve endings up there. The inner ear is what converts the vibrations we feel (either via the eardrum-bones or some other form of vibration transmission) into electrical signals through the movement of hairs giving us the perception of what we call sound, but that inner ear doesn't have the hairs required to detect frequencies higher than 20khz (or lets say, 22khz in young humans with exceptional hearing ability).
Therefore, causing the eardrum, or the bone, or even the brain to vibrate at a higher frequency does not in of itself prove that it is felt or 'detected' by the conciousness of the person.

It's an amazing world we live in when you think about it, we are constantly bombarded by an insane range of wavelengths, from cosmic rays to radio waves, wireless and mobile technology, infrared and ultraviolet, x-rays, yet we are completely unware of it.
Old 25th March 2014
  #1770
Quote:
Originally Posted by Chris93 View Post
"Hearing, auditory perception, or audition is the ability to perceive sound by detecting vibrations,[1] changes in the pressure of the surrounding medium through time, through an organ such as the ear. Sound may be heard through solid, liquid, or gaseous matter.[2] It is one of the traditional five senses. The inability to hear is called deafness."

Chris
Quote:
The eye is an airborne ultrasonic window to the ear and, as such, extends the range of human hearing. The mechanics of ocularly transmitted ultrasound should be similar in all other respects to ultrasound delivered to the skin of the head or neck as vibration [15], with the eventual activation of the auditory cortex in normalhearing and deaf individuals...Source: ITJ - The International Tinnitus Journal - Eyes as Fenestrations to the Ears: A Novel Mechanism for High-Frequency and Ultrasonic Hearing
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