Where I live, there was a belief that getting a fright eventually causes jaundice leading to death if a special herb potion is not taken three times a day for two weeks. I remember people taking this potion which, obviously, causes the liver to go into overdrive to flush the body of all its toxins. People used to claim that more frequent urinations were a sign that the potion was working!
Yet another myth was to cover the ill with a high fever with tons of blankets to force profuse sweating in the false and dangerous belief it would drive the illness out with it!
Yet another myth was to cover the ill with a high fever with tons of blankets to force profuse sweating in the false and dangerous belief it would drive the illness out with it!
To follow up on the network problem I described, not too long after that happened I was informed that the network engineers reprogrammed the Cisco routers to prevent the problem from happening again. Also, the problem happened roughly about 15-years ago. Don't know how much things may have changed since then.
Speaking of myths, some people appear to believe an FFT analyzer can measure everything important to know about audio device performance. Just goes to show human cognition is strongly affected by biases and heuristics:
https://www.sog.unc.edu/sites/www.sog.unc.edu/files/course_materials/Cognitive Biases Codex.pdf
https://en.wikipedia.org/wiki/List_of_cognitive_biases
https://www.sog.unc.edu/sites/www.sog.unc.edu/files/course_materials/Cognitive Biases Codex.pdf
https://en.wikipedia.org/wiki/List_of_cognitive_biases
If I'm guessing which "cult" place you mean - care to list the parameters they are not checking for? The measurements are not all FFTs...
For one thing there are a few detailed threads that in part discuss some things we don't measure very well. Threads I am thinking of were started by Pinox76 here and over there (IIRC there are two over there). The one here is at:
https://www.diyaudio.com/community/...ve-non-linear-distortions.379592/post-6852877
Time domain transient events, non-time-invariance, signal-correlated noise modulation, etc., are a few examples of things that may not show up in a useful way on FFTs. In addition typical audio FFTs discard phase information. Some people seem to believe phase doesn't matter because humans are insensitive to it. That view can be quite wrong in some circumstances as can be heard from the files available at: https://purifi-audio.com/2019/12/07/amfm/ ...The files only differ in the relative phase of some spectral components.
There are also some of writings of Earl Geddes on the value of THD+N, SINAD, etc.
http://www.gedlee.com/Papers/papers.aspx
To quote Dr. Geddes: "The bottom line here is that we know so little about how humans perceive the sound quality of an audio system, and in particular the loudspeaker, that one should question almost everything that we think we know about measuring it. From what we have found most of what is being done in this regard is naive."
Yet some people have gone so far as to conclude from FFT data that an audio device must be literally audibly transparent to any human on earth.
https://www.diyaudio.com/community/...ve-non-linear-distortions.379592/post-6852877
Time domain transient events, non-time-invariance, signal-correlated noise modulation, etc., are a few examples of things that may not show up in a useful way on FFTs. In addition typical audio FFTs discard phase information. Some people seem to believe phase doesn't matter because humans are insensitive to it. That view can be quite wrong in some circumstances as can be heard from the files available at: https://purifi-audio.com/2019/12/07/amfm/ ...The files only differ in the relative phase of some spectral components.
There are also some of writings of Earl Geddes on the value of THD+N, SINAD, etc.
http://www.gedlee.com/Papers/papers.aspx
To quote Dr. Geddes: "The bottom line here is that we know so little about how humans perceive the sound quality of an audio system, and in particular the loudspeaker, that one should question almost everything that we think we know about measuring it. From what we have found most of what is being done in this regard is naive."
Yet some people have gone so far as to conclude from FFT data that an audio device must be literally audibly transparent to any human on earth.
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And some people believe they can hear the brownian motion of air molecules in their listening room. Doesn't change the fact that the Nordost Switch is a scam.
You keep repeating this nonsense. Phase difference is not what you hear. The rotation of phase has resulted in amplitude difference which is the reason why those files sound different. Human hearing is sensitive to amplitude and pitch, not phase.
The leader used to describe some devices as audibly transparent in some of the device reviews. Here's a quote on that subject: "...there is a point in distortion and noise where we can declare a piece of equipment as audibly transparent." https://www.audiosciencereview.com/.../averlab-understanding-thd-n.7948/post-193033
The FFT shows the spectral lines are the same for both files. Therefore in the frequency domain the only thing that has changed is the phase of some frequencies. Of course that can change crest factor in the time domain, etc. That's how the math works, both views amount to different ways of looking at the same thing. Question is whether the FFT fooling you or giving you useful insight when phase is discarded?
It is very misleading to claim that phase is the only difference in those files. And all of this has nothing to do with validity of measurements or FFT.
What might that point in distortion and noise be? Have you any studies that show humans can hear below that point in controlled listening tests?
What would make anyone think that steady-distortion and phase-free FFTs can lend useful insight into everything that is audible? AP doesn't claim that. They claim to measure 'figures of merit.' So where does the kind of thinking I linked to come from anyway?
In the frequency domain phase is exactly the difference. The time domain representation is always going to have a different waveshape if the FFT, including phase information, is different. Always.
So what. When listening files who cares about frequency domain phase. And this still has nothing to do with validity of measurements or FFT. Totally useless marketing gimmick.
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