Why did Amir got it wrong ?
Fourier methods are the basis of audio design and at the heart of psycho-acoustic research...We all benefit from Fourier methods...
i only say this to be CLEAR about my next point..
What are Fourier methods : a very complex mathematical subject i will not enter in details for the goal of this discussion...
Suffice to say that the Fourier approach inspire some theory of hearing which claim that the ears/brain compute the spectral characteristic, and amplitude and duration and phase of any natural sounds or of any speech sounds or of any musical timbre playing tone by dissecting all aspects of these natural or human produced sounds and REDUCE them to be a LINEAR sums and a linear products of these ABSTRACTED FACTORS and only of that : frequencies, amplitude,phase, duration...No qualities are real, save these abstract measurable factors...
In a word the ears/brain are supposed to compute the qualitative WHOLENESS of any natural or musically produced sounds because all these qualities and all aspects of these sounds MUST be reducible to linear relation between, frequencies , amplitude and phase and duration...
This Fourier approach had been very successfully applied in the electronic design of gear, thanks to Fourier we have Dac and cd among other marvels...
Now if we come back to the hearing theories...
it is a well known fact for 60 years that the hearing theory frequencies based inspired by Fourier linear methods are not able by itself alone to explain hearing...
The experiment of Magnasco ande Oppenheim that Amir minimize and distort from his real results and separate from the conclusion of Magnasco and Oppenheim , because he minimize this experiment by claiming it was only a test of perception threshold forgetting to say the essential about these human hearing threshold : they exceed any possible explication in the window of Fourier theory... It is the reason why Oppenheim and Magnasco appeal clearly in hearing theory field for experiments in the ecological hearing theory domain...
What it means ?
it means that the natural sounds and musical sounds qualities are WHOLENESS perceived as WHOLE qualities IRREDUCTIBLE to the linear composition of abstract factors from the Fourier methods : frequencies, amplitude, phase and duration among others, Which are ALL LINEARLY connected in a window where it is impossible to precise infinitely one factor as frequency and at the same time infinitely precise a factor as duration they are all linearly bounded .... it is the Fourier uncertainty limit , analogous to the Heinsenberg uncertaintu in quantum mechanics...
Magnasco and Oppenhein testing human hearings for accuracy discovered that this accuracy exist in A TIME DEPENDANT DOMAIN... Whats does it means ? it means that unlike Fourier methods which are time INDEPENDANT, the human ears perceive and distinguish out of the Fourier mathematical uncertainty bounds the difference in time between different qualitative sounds when the sounds are played as they appear in a natural context , in a time ordered preference , sharp attack, long decay, not so much in the reverse direction...
in the words of Magnasco and Oppenheim :
« Time-reversal symmetry breaking is a key feature of many classes of natural sounds, originating in the physics of sound
production. While attention has been paid to the response of the auditory system to ‘‘natural stimuli,’’ very few
psychophysical tests have been performed. We conduct psychophysical measurements of time-frequency acuity for stylized
representations of ‘‘natural’’-like notes (sharp attack, long decay) and the time-reversed versions of these notes (long attack,
sharp decay). Our results demonstrate significantly greater precision, arising from enhanced temporal acuity, for such
sounds over their time-reversed versions, without a corresponding decrease in frequency acuity. »
production. While attention has been paid to the response of the auditory system to ‘‘natural stimuli,’’ very few
psychophysical tests have been performed. We conduct psychophysical measurements of time-frequency acuity for stylized
representations of ‘‘natural’’-like notes (sharp attack, long decay) and the time-reversed versions of these notes (long attack,
sharp decay). Our results demonstrate significantly greater precision, arising from enhanced temporal acuity, for such
sounds over their time-reversed versions, without a corresponding decrease in frequency acuity. »
Then Amir confused two things in his posts answering me , he confused the time dependant dimension of human hearings which works non linearly out of the Fourier bounds with the usual relative duration domain in the Fourier window which is an independant time domain because it imply a bounded linear relation and a reversible one between frequencies and time ...He did not understand the article of Magnasco and Oppenheim nor my argument then..
He also confused the true goal of this experiment which was not a mere simplistic experiment about the treshold of human hearings as his claim in a dismissive manner at the begining of the debate in his posts, but a PROOF that human hearings beating the uncertainty limits of the linear Fourier time independant WINDOW , the human hearings cannot be explained by the Fourier method ALONE so useful and INDISPENSABLE for designing and measuring electronic material design it was, it is, and will be...
Van Maanen know all that , it is why i cited many of his articles... Amir dismiss them as marketing propaganda... He even ask me the proof that his speakers sound good 😁... Only fools will believe him, no people able to read science...I dont want to insult here, but the Oppenheim and Magnasco articles are not so hard to read, nor the Van maanen articles..
Now If Fourier methods are not enough to give us a hearing theory which is able to explain human performance, what other approach will do it ?
Here the answers come from Magnasco and Oppenheim mouth :
«The results have implications for how we understand the way that the
brain processes sound, a question that has interested scientists for a long
time. In the early 1970s, scientists found hints that human hearing could
violate the uncertainty principle, but the scientific understanding and
technical capabilities were not advanced enough to enable a thorough
investigation. As a result, most of today's sound analysis models are
based on old theories that may now be revisited in order to capture the
precision of human hearing.».........................
brain processes sound, a question that has interested scientists for a long
time. In the early 1970s, scientists found hints that human hearing could
violate the uncertainty principle, but the scientific understanding and
technical capabilities were not advanced enough to enable a thorough
investigation. As a result, most of today's sound analysis models are
based on old theories that may now be revisited in order to capture the
precision of human hearing.».........................
"Such increases in performance cannot occur in general without some
assumptions," Magnasco said. "For instance, if you're testing accuracy
vs. resolution, you need to assume all signals are well separated. We have
indications that the hearing system is highly attuned to the sounds you
actually hear in nature, as opposed to abstract time-series; this comes
under the rubric of 'ecological theories of perception' in which you try to
understand the space of natural objects being analyzed in an ecologically
relevant setting, and has been hugely successful in vision. Many sounds
in nature are produced by an abrupt transfer of energy followed by slow,
damped decay, and hence have broken time-reversal symmetry. We just
6/7
tested that subjects do much better in discriminating timing and
frequency in the forward version than in the time-reversed version
(manuscript submitted). Therefore the nervous system uses specific
information on the physics of sound production to extract information
from the sensory stream.
"We are also studying with these same methods the notion of
simultaneity of sounds. If we're listening to a flute-piano piece, we will
have a distinct perception if the flute 'arrives late' into a phrase and lags
the piano, even though flute and piano produce extended sounds, much
longer than the accuracy with which we perceive their alignment. In
general, for many sounds we have a clear idea of one single 'time'
associated to the sound, many times, in our minds, having to do with
what action we would take to generate the sound ourselves (strike, blow,
etc)."
More information: Jacob N. Oppenheim and Marcelo O. Magnasco.
"Human Time-Frequency Acuity Beats the Fourier Uncertainty
Principle." PRL 110, 044301 (2013). DOI:
10.1103/PhysRevLett.110.044301
assumptions," Magnasco said. "For instance, if you're testing accuracy
vs. resolution, you need to assume all signals are well separated. We have
indications that the hearing system is highly attuned to the sounds you
actually hear in nature, as opposed to abstract time-series; this comes
under the rubric of 'ecological theories of perception' in which you try to
understand the space of natural objects being analyzed in an ecologically
relevant setting, and has been hugely successful in vision. Many sounds
in nature are produced by an abrupt transfer of energy followed by slow,
damped decay, and hence have broken time-reversal symmetry. We just
6/7
tested that subjects do much better in discriminating timing and
frequency in the forward version than in the time-reversed version
(manuscript submitted). Therefore the nervous system uses specific
information on the physics of sound production to extract information
from the sensory stream.
"We are also studying with these same methods the notion of
simultaneity of sounds. If we're listening to a flute-piano piece, we will
have a distinct perception if the flute 'arrives late' into a phrase and lags
the piano, even though flute and piano produce extended sounds, much
longer than the accuracy with which we perceive their alignment. In
general, for many sounds we have a clear idea of one single 'time'
associated to the sound, many times, in our minds, having to do with
what action we would take to generate the sound ourselves (strike, blow,
etc)."
More information: Jacob N. Oppenheim and Marcelo O. Magnasco.
"Human Time-Frequency Acuity Beats the Fourier Uncertainty
Principle." PRL 110, 044301 (2013). DOI:
10.1103/PhysRevLett.110.044301
What these deep analysis by Oppenheim and Magnasco means for understanding what is an ecological theory of hearing ?
In a simnple sentence because my post is already too long for many , the abstract linear Fourier conmposition of factors as frequencies, duration, phase, and amplitude are not ENOUGH information to recompose the sounds qualities which are as integral wholeness RECOGNIZED and differentiated accurately ( in the Magnasco and oppenheim experiment) by the ears/brain after a long natural evolution and the relation between these sound qualities and our own abilities to GENERATE these sound qualities and control them on any musical instrument and with the voice is a crucial part of the ecologixcal theory of hearing and future experiments ....
Then in conclusion to stay short and sweet;😊
Amir claims that his set of linear time independant measures extracted from material design of gear , when he used to verify and falsify the market gear specs cannot be extrapolated in any way to a LINEAR predictive affirmation about the sound qualities of this material design by the set of measures ALONE ....Because human hearing extract and perceive information attuned to his structure and history by evolution and by training, and these qualitative information are sometime out of the uncertainty limit of the Fourier windows... They are qualities that cannot be completely reduced to abstract mathematical physics factors as : frequencies, amplitude phase and duration; they even cannot be understood doing so ...
The ears brain dont work in the same artificial controlled context as Fourier tools did, nor it work the same way ..
Then Amir say that he listen as we do, for sure he did , but this saying mask the fact that if the system did not measure as he hope he will declared it "non musical"...He even said it is useless for him to listen to an amplifier or to speakers as Magnepan that dont measure perfectly... He is wrong, some qualities are not measurable by Fourier tools and Magneplanar speakers, so imperfect their measure can be, could be embedded in a dedicated acoustic room specifically for them where they will shine... I know because i could tune this room, it will not be perfect, but music is in the controlled imperfection...Perfection is death...
For his bragging about auditory test, i see that Amir confuse testing for qualitative accuracy with testing for quatitative resolution between Fourier abstract factors in hertz and decibels and duration, and testing a musical trained maestro for qualitative timbre perception and musical qualities... i will not cite a Van Maanen article about why it is not so sad a slight lost of hearing with age than most people think... My post is too long for some hateful brain ,who will ask me to stop and go, even if i side with them about listenings fundamentals...
In a word the relation between well measured design piece and their qualitative listening tests is not LINEAR ... The design can be behave well under Fourier linear analysis tools and can be evaluated bad by human hearings... it is better to know what we do designing a piece of gear, there is no universal perfect recipe to design PERFECT gear for all possible needs... And human ears are not tools...The brain is not a computer...not a Turing machine and not even a non-Turing machine ...
