I've (quite regularly) emphasised in the past that we must learn to hear for perceptual evaluation purposes.
As Bech&Zacharov wrote in their preface:
Although they do concentrate on the professional/scientific listening tasks, it is the same for personal use. Maybe even more important as one might have to live with a unlucky choice. ....
As Bech&Zacharov wrote in their preface:
(Bech/Zacharov; Perceptual Audio Evaluation - Theory, Method and Application, John Wiley & Sons, 2006, xii)
Although they do concentrate on the professional/scientific listening tasks, it is the same for personal use. Maybe even more important as one might have to live with a unlucky choice. ....
Detecting a difference
Human perception can be easily fooled, mine included. As an engineer in training I built a class A solid state amp. My neighbour had bought an expensive commercial amp and speakers. I so liked the speakers that I found the money to buy the same. However my setup never sounded like his, even though we had the same room shape and similar furnishings and we tried the same sound sources too. Discontented I saved up and bought the same amp. It was great for about a week, then I started noticing things that I didn't like.
I had been fooled into thinking that the high cost commercial amp was better than my home-brew amp just because it was different.
Human perception can be easily fooled, mine included. As an engineer in training I built a class A solid state amp. My neighbour had bought an expensive commercial amp and speakers. I so liked the speakers that I found the money to buy the same. However my setup never sounded like his, even though we had the same room shape and similar furnishings and we tried the same sound sources too. Discontented I saved up and bought the same amp. It was great for about a week, then I started noticing things that I didn't like.
I had been fooled into thinking that the high cost commercial amp was better than my home-brew amp just because it was different.
I very much like "The Psychology of Music" by Diana Deutsch, particularly the chapter
on grouping mechanisms:
http://deutsch.ucsd.edu/pdf/PsychMus_Ch9.pdf
on grouping mechanisms:
http://deutsch.ucsd.edu/pdf/PsychMus_Ch9.pdf
Are you sure time can exist without frequency? Thats the way we measure it. ( the earths rotation, a pendulums or atoms frequency )
Non mathamatical time is more obscure than frequency so that comment is useless.
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In more recent years, cognitive science has started to gain the interest of musicologists: https://www.cogsci.msu.edu/DSS/2008-2009/Huron/HuronSweetAnticipation.pdf
Yes, a very influential researcher & voice in auditory perception research
The whole field of Audio Scene Analysis & how auditory perception dynamically groups individual sounds into audio streams from moment to moment & how there is often a tension in this decision - it's only a best guess most of the time.
Jakob mentioned Top-down Vs bottom-up approaches & it is generally recognized that both are at play so that the prediction of what sound instant should come next will be compared with the actual sound that arrives at the eardrum. If this match-up doesn't happen then it involves more processing to analyse if this is a sound from a glitch in the existing soundstream or the start of a new sound stream coming from another sound creating object "perceptual fusion and separation"
I'll repeat again here that I feel this tension is at the heart of why some systems lead to fatigue (usually digital audio) & some systems feel very natural sounding & relaxing to listen to.
When we listen to sound in nature we still have these decisions & issues but they are at a lower level than when we are listening to a stereo playback system trying to create an illusion of a natural 3D soundfield between two speakers.
Already our auditory system is on notice that something is not quite right & not receiving the natural presentation of the soundfield as we would experience it if the group of musicians was in front of us. But this system is close enough to allow us suspend our belief enough to immerse ourselves in the performance in a way satisfying enough to mimic the real thing
What is crucial to our making sense of the auditory world is the stability of each auditory stream as it progresses through time - we don't want to suddenly confuse the double bass with the baritone. So the rules by which this grouping occurs & the non-violation of these rules all through a music track is crucial to our sense of the playback sound being as natural as possible, interesting & relaxing to listen to.
This can be profound when heard - it's like something clicks into place about how the whole playback now sounds. I reckon this occurs when the level of rightness reaches a certain threshold of boxes ticked - when the illusion is sufficiently strong that it can be enjoyed without being constantly made aware that it is an illusion & not natural sounding.
I have no clue what you are talking about? I must be thick as it makes no sense to me?
Let's presume Bruno has made some progress in correlating measurements with perception, how do we wring it out of him?
Demian's original files are still online here Index of /ProAudio/Demian_Tri _Band _files
Cheers
Alan
If you mean derivative in the normal everyday sense then yes. However, be aware that if a signal is brief then not only can we not determine 'the frequency' but in reality the signal does not have a frequency but a significant band of frequencies.mmerrill99 said:
Yes two different "plots' but they show the same phenomenon and contain the same information. Two different views of the same reality.
You keep dragging FFT into this conversation. I am not sure why. FFT is a popular method for getting from a sampled time waveform to a sampled frequency spectrum. Not what I am talking about.
We may make more progress if ears are left out. What I am saying does not depend on how ears work.
They are random sinewaves. I believe I am correct in saying that the Fourier transform of random noise (in the time domain) is random noise (in the frequency domain) - the grass at the bottom of an FFT plot.
What I meant was that we develop our understanding of how the world works by seeing how things change with time, so naturally we grow up thinking that time is somehow more fundamental and real than frequency. Physicists have to learn to think differently, as do crystallographers and electronic engineers.
Once again you are dragging FFT into the discussion. As Jakob2 explained, if we have phase information then we have all we need. Phase is usually omitted from an FFT plot because in most cases people are not interested in seeing it. However, the FFT process delivers phase as well as amplitude, so we have all we need to perform an Inverse FFT to get back the original waveform.
On a moment to moment basis means you are in the time domain, so of course it looks like a waveform and not sine waves. The answer is included in the question. However, it is equally valid and real to see things in the frequency domain: then there are sinewaves hitting the eardrum and no waveform. What you don't seem to get is that these two different views of reality are equally valid and real and contain exactly the same information.mmerrill99 said:
That may or may not be true; I am not in a position to comment. However, I can assure you that time domain noise is lots of tiny random sine waves i.e. frequency domain noise. How we hear it is a different question entirely.
Yes, I mean derived - I should avoid terms which also have a mathematical significance. Again I mean just a solitary point on a signal waveform, not a short signal waveform - so what I was saying is that a sufficient sampling of the waveform over time is needed before frequency can be established - the longer the time period the more accurate the frequency, as you said.
Yes but seldom presented
OK
I was countering the idea put forth (not by you) that the ear? or hearing? performs an FFT or FFT-like processing
But the level of that grass is not the noise floor level, right?
OK, I see but really frequency is amplitude variation over time & frequency is derived from these two - it's not really a direct phenomena that we encounter naturally.
Sure
There is a useful test signal called pseudo-random noise. You add say 65536 sine waves of equal amplitude and random phase together. You can do this tediously by computing all the sine waves and adding them or by simply putting a constant magnitude and random phase value into 65536 FFT bins and taking the inverse transform. The result is indistinguishable from random noise and made up of sine waves. You can do this at any sampling frequency or length of transform.
It's pseudo-random because you have limited the crest factor by choosing a finite number of bins, a real Gaussian process has a finite probability of very large values.
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Yes but auditory perception does not deconstruct random noise into these sine waves for analysis - as I said it would be very inefficient
Just because what is perceived as random noise can be constructed from a large number of sine waves doesn't mean the reverse process therefore occurs
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Different should be perceived as better only if it is.
must admit though I have been stumped between two versions of different and could not decide.
Everything seems to be a trade off of some sort.
But like Merrill says there is a place where the the stars and planets align and if never experienced is a bit hard to explain.....took me 40 yrs to find it and still really have no idea what ‘it’ is! 😛
What I'm saying is that there is no such thing in the real world as "the frequency domain" - frequency is derived from amplitude & time - we don't directly encounter derived aspects. I was answering DF96 comment
"That is probably because like most of us you have not spent much time exposed to frequency domain phenomena"
That's interesting, it really must be a perception thing, I see the frequency domain as more "real" than the time domain. Look at an oscilloscope trace then a spectrum analyser, which is more "real" to you?
that's why i suggest people use blind preference listening rather than "spot the difference" style listening
Yes, I'm interested in what the "it" is & look towards auditory perception for the answer - still searching but there are hints emerging
As requested:-
Technicolor in the right hands was and still is the ultimate optical process in analog emulsion colour cinematography, and is a subject of great fascination to me.
Invented by Herbert Kalmus, Technicolor, like Western Electric sound, had a near monopoly in the cinema industry for nearly 25 years. Technicolor owned all the Technicolor cameras, Technicolor RGB film stock, Technicolor processing and made in house all the CMYK Technicolor projection prints - and to a very high standard, too. It’s only problem was Herbert’s wife Natalie, who tyrannically oversaw the major Hollywood studio’s on site soundstage colour management of how Technicolor recorded certain ‘difficult’ colours.
Because Technicolor could handle saturated colours, she wanted it that way- no matter what a director wanted, so that Technicolor could sell itself over and over again all around the world. This is why MGM’s ‘The Adventures Of Robin Hood’ looks so completely over the top. If Natalie wasn’t satisfied with the dailies, she had the contractual power to pull a production, and the studios hated her for it.
In Europe it was a slightly different matter. Technicolor’s lab in Paris was a lot more tolerant with continental film directors and cameramen, and the greatest of them all to use Technicolor was cameraman Jack Cardiff who worked for filmmakers Michael Powell and Emeric Pressburger, who amongst other achievements, wrote and directed ‘Black Narcissus’ - possibly the greatest colour film ever made. Cardiff was adventurous enough to understand that Technicolor could simultaneously record both saturated colours and pastel washes within the same frame, and reproduce the most subtle or extreme colours anywhere within the tonal range of light.
When horror bag Natalie dutifully turned up on the set at Pinewood to throw her weight around yet again, Powell politely listened, said yes to everything she demanded, and after she left the set, ignored her terms and conditions completely. The result is a masterpiece in high fidelity colour.
So in real terms, Technicolor is the visual equivalent to 2inch wide stereo tape with perfect miking running at 30 inches per second, and is the closest anyone will ever see human colour vision as it is on a cinema screen.
ToS
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