KeithEmo
Member of the Trade: Emotiva
- Joined
- Aug 13, 2014
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First of all, yet again, you are assuming that there is some well established standard for "what quantities of jitter cannot possibly be audible".
In fact no such standard exists.
(Although a few tests have shown that, under certain specific conditions, relatively high levels of jitter may be inaudible.)
Your second assertion is technically incorrect... although, yet again, you persist in describing "inaudible levels" as if such a clearly established standard actually existed.
(When you're talking about things like jitter sidebands, which occur at audible frequencies, there is no such thing as "inaudible",
there is only "too far below a specific noise floor to be heard".)
Start with 100 watts of pink noise....
Now add 1 watt of pink noise....
You will find that the added pink noise, spread over the entire spectrum of the original noise floor, will result in an inaudible rise of a tiny fraction of a dB in the noise floor....
Now, start with the same 100 watts of pink noise....
And add 1 watt of a pure 440 Hz sine wave....
You will find that the 440 Hz tone, at exactly the same level as the added pink noise, but limited to a single frequency, will result in a clearly audible tone....
Your last one is easy.....
Up until recently "it was well known" that "the range of frequencies audible to human beings went from about 20 Hz to about 20 kHz.....
Until recently published test results proved that humans can actually hear as low as 10 Hz....
(And, now, knowing that one end of the "well established range" was wrong, I'm not sure how much faith I place in the "well known limit" at the other end.)
https://www.ncbi.nlm.nih.gov/m/pubmed/15273023/
https://www.sciencedaily.com/releases/2015/07/150710123506.htm
Note that, in the article in Science Daily, while an MRI was used initially, "All persons concerned explicitly stated that they had heard something --".
In fact no such standard exists.
(Although a few tests have shown that, under certain specific conditions, relatively high levels of jitter may be inaudible.)
Your second assertion is technically incorrect... although, yet again, you persist in describing "inaudible levels" as if such a clearly established standard actually existed.
(When you're talking about things like jitter sidebands, which occur at audible frequencies, there is no such thing as "inaudible",
there is only "too far below a specific noise floor to be heard".)
Start with 100 watts of pink noise....
Now add 1 watt of pink noise....
You will find that the added pink noise, spread over the entire spectrum of the original noise floor, will result in an inaudible rise of a tiny fraction of a dB in the noise floor....
Now, start with the same 100 watts of pink noise....
And add 1 watt of a pure 440 Hz sine wave....
You will find that the 440 Hz tone, at exactly the same level as the added pink noise, but limited to a single frequency, will result in a clearly audible tone....
Your last one is easy.....
Up until recently "it was well known" that "the range of frequencies audible to human beings went from about 20 Hz to about 20 kHz.....
Until recently published test results proved that humans can actually hear as low as 10 Hz....
(And, now, knowing that one end of the "well established range" was wrong, I'm not sure how much faith I place in the "well known limit" at the other end.)
https://www.ncbi.nlm.nih.gov/m/pubmed/15273023/
https://www.sciencedaily.com/releases/2015/07/150710123506.htm
Note that, in the article in Science Daily, while an MRI was used initially, "All persons concerned explicitly stated that they had heard something --".
I'll just take two points rather than refute all of them individually because they're all effectively the same. Everything you've stated is true or true under certain circumstances but it's all irrelevant as a response to my post and irrelevant to the thread title and is therefore off topic.
1. And when are they present in such large quantities? Maybe a faulty device? I don't think such quantities were even present in the earliest CD player when digital audio was first launched to the public.
2. A single sideband frequency at an inaudible level cannot be "more audible" than a spread of sidebands with the same average energy level because it's inaudible!!
1. I don't overlook it, I continually point it out to you but you carry on using circular logic anyway!
2. That's clearly false! That view was based on an existing body of un-established, unreliable evidence but was the best available at the time (IE. Before science established a body of reliable evidence!).
3. Quite a significant percentage? Can you give just one example of audio science that we knew 50 years ago but has since proved to be wrong?
G