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BlueRockinLou:

We are definitely probing into the future here. Imagine having mics, cables, recording consoles, amps, speakers, all with 100 kHz bandwidth. Crazy talk! But who knows someday? And special metering to isolate the "EEG Factor", even future "EEG Wars" where producers maximize and over-compress the effect, followed by pleas to "return to the good old days of a natural, uncompressed EEG band..."

And maybe it is so unpredictable that we are better off with it filtered out. Some of the higher-priced speaker cables have networks to filter out content above 20 kHz - another discussion altogether.

Just when life seemed to be getting simpler.:rolleyesno:
 

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Maybe this is a simplistic view on things but I can help but think that the waves formed captured digitally are not limit to 20KHz om the recording side. It stands to reason then that the waveform captured by the recording already contain the effects of waveform shaping caused by the higher order harmonics.

Has any quantified how high the harmonics go for all the particular instruments? If not, then this is sheer speculation and taking a bit of science and running with it with no proof.
 

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Discussion Starter #23
Maybe this is a simplistic view on things but I can help but think that the waves formed captured digitally are not limit to 20KHz om the recording side. It stands to reason then that the waveform captured by the recording already contain the effects of waveform shaping caused by the higher order harmonics.
A logical assessment, indeed! And since most musical instrument harmonics fall below 20kHz, there's literally nothing to lose by restricting digital sampling to that upper limit.
 

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A logical assessment, indeed! And since most musical instrument harmonics fall below 20kHz, there's literally nothing to lose by restricting digital sampling to that upper limit.
That's my thinking too.
 

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Oohashi and his colleagues recorded gamelan to a bandwidth of 60 kHz, and played back the recording to listeners through a speaker system with an extra tweeter for the range above 26 kHz.
Unfortunately, your reference #2 is not actually a reference. That Oohashi "paper" has caused no end of problems over the years. Note that I put the word "paper" in quotes. It was written just like other scientific papers and originally published in a recognised scientific journal. So far so good but the next bit is what's caused all the problems: It was not actually a scientific paper and it was not published as a scientific paper! It was an advert and it was published in the advertisement section of the journal, not the actual scientific paper section! That extra tweeter/amp combo referred to, is the product Oohashi developed and manufactured and was trying to sell. It was an extremely elaborate and clever bit of advertising, so convincing that it's been referenced and quoted countless times as an actual scientific paper, even by other impartial respected scientists and experts, let alone by industry marketing depts with vested interests in their own ultrasonic products.

To address some of the other points:

1. There is not, AFAIK, data on the >20k content of all instruments but i have seen data for some of them. Violin for example was about 4% of it's total frequency output being above 20k. Some instruments, particularly metallic, struck instruments can have significant ultrasonic content; cymbals, gamelan, etc.

2. Until relatively recently, all studio and music recording mics' frequency response rolled off dramatically at or below 20k. There are now some with higher freq response (as high as 50k in some cases) but they're still not widely used.

3. All the evidence supports an extreme limit of 22k for human hearing, with a practical limit of 20k still being at least 2k higher than 99.9% of the adult population can detect. Despite countless studies/tests spanning decades, there is still no reliable evidence to the contrary (bearing in mind Oohashi does not qualify as reliable evidence).

4. Ultrasonic frequencies can interact and become audible. However, there are very specific conditions required. For example, significant ultrasonic energy can cause distortion in some equipment (amps/speakers) not designed for ultrasonic frequencies. This can cause tones to be generated within the audible hearing spectrum. This effect is called Inter-Modulation Distortion (IMD). Two or more individual frequencies can interact and produce measurable and audible additional tones. This is Frequency Modulation but for it to be audible, both/all the frequencies causing the modulation effect must be within the hearing spectrum. If any of the frequencies are outside the hearing spectrum (ultrasonic), the modulation effect will disappear. What you will hear is indistinguishable from the same sound but with those ultrasonic frequencies removed. If you have access to a square wave generator, there's an extremely simple test you can run yourself to prove this.

5. While vinyl can theoretically contain frequency content up to around 30k, beyond about 16k it's response rolls-off significantly and distortion increases significantly. CD can't contain anything above 22k but there is no roll-off in response or increase in distortion until that point. Between 16k and 22k, CD is orders of magnitude more accurate than vinyl and, if one chooses to accept the evidence, what goes on beyond 22k is irrelevant.

6. Starting from the early 1970's, commercial vinyl presses went digital! IE. The (analogue) pre-masters created by the mastering engineers were stored internally by the vinyl press as digital audio and that is what was pressed. Early models were 13bit/32k but by the end of the 1970's the different commercial press manufacturers utilized different digital audio formats, anywhere from 13bit - 15bit and 32k - 50k. This often overlooked fact makes a bit of a nonsense out of much of the digital vs vinyl debate.

7. Distortion is anything which changes a signal and is inherently neither good nor bad or rather, it can be either good or bad. Even the same type of distortion and be both good or bad, depending entirely on context. Due largely to ignorance, distortion is generally a dirty word amongst audiophiles and this unfortunately usually precludes any meaningful discussion about distortion. To get around this misappropriation of the term, some audiophiles seem forced into illogical, irrational or even straight up lies to support their subjective perceptions of good and bad. "Vinyl has higher resolution or sound quality than digital" for example, and of course, many manufacturers are more than willing to take advantage of this fact in their marketing.

8. A common thread in audiophilia is the inability to differentiate between the contents and the container. This leads to all kinds of logical fallacies, not just between digital and vinyl but also between different formats of digital, CD and so called HD audio being a classic example. In reality, High Definition audio doesn't have even the tiniest bit more definition than CD and in some cases it actually has less but by manipulating the contents of the container and misrepresenting the facts about containers, it's trivial to prove to all but the most well informed that HD audio not only exists but is significantly better.

9. Directly related to #8, is the purpose and functionality of the different containers. The LP is a format specifically designed and suited for critical listening, IE. Where listening to the contents of the LP is the sole activity. You cannot for example, listen to an LP on a car stereo whilst driving or using earbuds whilst jogging or sitting on the train/bus/metro/plane/bike, etc. This difference in use, significantly affects what we put in these different containers. A typical example is the use of heavy compression, which is generally bad when critically listening; in addition to dramatically reducing dynamic range, it also affects frequency response, accuracy of the sound stage, frequency separation (or "detail") and other factors. However, when not critically listening, heavy compression (significantly reducing dynamic range) is a very good thing! It allows us to hear details, entire phrases, sections or instruments which would otherwise completely disappear beneath the ambient noise. This is an important and often overriding concern when creating digital audio content and necessitates compromising the audio quality for the critical listening scenario. HD audio is commonly a critical listening only scenario and so we don't have this concern and don't need to employ any compromise to suit the non-critical listening scenarios. LP is strictly critical listening only and can't technically accept the heavy compression used in digital anyway. All this is about content rather than container, we can just as easily put an uncompromised HD audio mix into the CD format and the result would be indistinguishable from the HD original.

Some involved in this thread already seem well informed and I'm sure I've not said anything they don't already know. Maybe some of it will be useful to others and/or initiate a bit of discussion?

G
 

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Discussion Starter #28

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Unfortunately, your reference #2 is not actually a reference.
Oh, but it is a reference. Turns out just not a good one. Wish I'd known that earlier. :R

3. All the evidence supports an extreme limit of 22k for human hearing, with a practical limit of 20k still being at least 2k higher than 99.9% of the adult population can detect. Despite countless studies/tests spanning decades, there is still no reliable evidence to the contrary (bearing in mind Oohashi does not qualify as reliable evidence).
Are you certain that's not 99.94% instead?
I had trouble finding any of those studies. Can you post a few links, please?

5. CD is orders of magnitude more accurate than vinyl and, if one chooses to accept the evidence, what goes on beyond 22k is irrelevant.
How many (scientific) orders of magnitude? The "evidence" available relies on scientific principles discovered to-date. What does the future hold? Are you surmising that sound reproduction has reached a pinnacle and no further improvement is possible? What of the scientific tests and instruments not yet developed that may be able to establish a statistically significant correlation between hearing and subtle acoustic events? The earth is flat, indeed!
 

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How many (scientific) orders of magnitude? The "evidence" available relies on scientific principles discovered to-date. What does the future hold? Are you surmising that sound reproduction has reached a pinnacle and no further improvement is possible? What of the scientific tests and instruments not yet developed that may be able to establish a statistically significant correlation between hearing and subtle acoustic events? The earth is flat, indeed!
There are those who seem to embrace limitation. Do not let them slow you or turn you from your chosen path.
 

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16/44 does not contain as much information as analog. When we increase the density of information with higher resolution, the sound becomes MORE analog-like. Digital is an analog signal that has been given a bath in software.

It is my opinion that analog sources have sharper images and superior soundstaging, simply because there is more information being conveyed to the loudspeakers and listener. Frequency response well past 20 kHz is evidence of this.


http://www.kvart-bolge.com/#!Audiophile-Myths-No-4-Hires-Audio-but-wait-a-minute/c1rr6/553ac80c0cf2836c87f2d045
 

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Discussion Starter #33
AudioPost;1327865 1. We have been able to measure "subtle acoustic events" for many decades and we can measure levels of subtlety way beyond (some or many orders of magnitude!) the ability of the human ear to detect.[/QUOTE said:
Apparently not subtle enough.

If it measures bad but sounds good, it is good!
If it measures good but sounds bad, it is bad!



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How about:
If it measures good but sounds bad, you've measured the wrong thing.
Yep, that's much better. As far as sound waves are concerned, we can measure ALL their physical characteristics extremely accurately. We can't measure people's perception of sound waves hardly at all though. So while we may have measured the wrong thing (the sound waves), we currently have nothing else we're able to measure. Maybe one day we'll be able to measure people's brains, their bio-chemical and bio-electrical reactions, their emotions and what they perceive and maybe recreate them without even needing to involve any sound waves in the first place. Until then, all we can do is measure the sound waves themselves and leave judgements about whether they're perceived as good or bad to individual opinion.

G
 

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After all, the story the pseudo-science paints is very convincing and infinitely more readable that a series of equations that that only engineers and math grads can comprehend.
Good point! All too convincing sometimes. I think that's because pseudo-science tries to appeal to common sense and oversimplified aspects of the world we live in. Biasing conductor insulation in a cable is one example.



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If you mean that by increasing the density of digital information we run the risk of degrading accuracy to analogue levels of accuracy then yes, possibly a fair statement. If you mean that analogue is more accurate than digital and that by increasing the density of digital information we would get more accurate digital, then no, your statement is utterly incorrect.
Increasing the density of digital information reduces quantization noise, the bugbear of digital reproduction. The evidence can be seen in Hi Resolution digital (higher than 16/44), which makes the stair steps smaller.... more analog-like wave forms are reproduced.

This statement is absolutely correct. The point you appear to be missing though, is that this fact is exactly what makes digital so inherently more accurate than analogue! Analogue attempts to perfectly record a continuously varying signal, which is possible only up to a combination of the physical limitations of electrical, electro-magnetic and mechanical components. Digital audio on the other hand just records data, namely; a relatively few coordinates which allow the original signal to be mathematically recreated perfectly. The fact that we can mathematically perfectly dissect and reconstruct a continuously varying signal is not disputed, except by "flat earthers" ignorant of the undisputed proofs or those deliberately lying about them.

G
High resolution digital approaches, perhaps exceeds, the capabilities of analog reproduction. 16/44, as the article I linked to points out, is a data lossy medium. All recording mediums can be said to be data lossy, some more than others.
 

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Discussion Starter #38
This was meant to be an informative and entertaining thread. When discovered that the thread's premise was questionable, I acknowledged that fact. Unfortunately, some members became extremely disrespectful and argumentative. Scientists embrace the unknown with open minds. That' how technology advances. Thread closed to further discussion.
 

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Let me be very clear. It is OK to disagree. It is not OK, however, to deride others, or a group, because one thinks that his/her view is more correct than another's view.

No matter how sure you are of your facts, there is always room for discussion. The discussion should be targeting ideas, not others. Calling others irrational, or referring to a group(e.g. audiophiles) similarly, is not the way we conduct discussions here. Keep to YOUR point and discuss what others say respectfully.

HTS has always required this kind of mutual respect and civil discourse and it is one of the things that set us apart from other forums. There are plenty of places you can go if you want to bicker or demean others. No one will be allowed to do it here.
 
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