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Old 12th October 2011, 10:58 AM   #16501
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Quote:
Originally Posted by PMA View Post
Thanks for the link, seems to be an interesting article. I am often saying that we examine deterministic periodic test signals, which is contrary to the nature of musical signals.

Hopefully I speak Russian
This paper stresses on possible un-deterministic properties of the transfer function, and its influence on output signals. Sine wave has minimum information, and any even narrow transmission channel can handle it. While music is an information dense signal, and limited channel transmission possibilities, caused by stochastic component of transmission function, can be a reason that information at the output is not complete.
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Old 12th October 2011, 12:13 PM   #16502
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Quote:
Originally Posted by VladimirK View Post
Here are some short translated parts of this paper:

Condition for the absence of information loss when converting the input X to output Y = G (X), including non-linear transfer function, is the presence of a single-valued inverse transform of H (V), reducing input X = H (G (X)).
Thus, in one transformation input to the output, a loss of information in a channel without noise does not occur, even if the transfer function is nonlinear.
Are you sure this is not just a way of saying that if you know the non-linerarity and it is time invariant you can undo it mathematically? If the distortion is bad enough the problem rapidly gets intractable and ultra sensitive to noise. This is similar to Weiner filtering in optics or inverting almost singular matricies.
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Old 12th October 2011, 12:28 PM   #16503
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Originally Posted by scott wurcer View Post
Are you sure this is not just a way of saying that if you know the non-linerarity and it is time invariant you can undo it mathematically? If the distortion is bad enough the problem rapidly gets intractable and ultra sensitive to noise. This is similar to Weiner filtering in optics or inverting almost singular matricies.
Hello, Scott
It is difficult for me to comment this professionally, I am sure you are write as for the important role of numerical artefacts. But Chumakov speaks on an analytical level, and states about the basic impossibility to recognize information in its complete form, if the transfer function is not comletely deterministic.
I attract attention to this paper, because I was impressed by complete coincidence of the conclusions made in the paper, with my listening experience and intuition. I for already few years do not care about linearity, but take all possible measures for lowering noise, use external power supplies, multystage RC filtering in PS, diode switching noise suppression, high quality parts, no NFB or very short-loop and fast current NFB, all-jFET schematics, SE class A, etc. All these measures are aimed at diminishing stochastic components of the transfer function.
I was very encouraged that my intuition has got analytical support. For a long time I listened, that distortions have a sub-class, called losses. Now I can imagine, about what losses people spoke.

Last edited by VladimirK; 12th October 2011 at 12:43 PM.
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Old 12th October 2011, 05:19 PM   #16504
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Here is another paper on stochastic nonlinearity

http://citeseerx.ist.psu.edu/viewdoc...=rep1&type=pdf
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Old 12th October 2011, 06:23 PM   #16505
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Thanks Vlad, I sent this on to Dick Sequerra. He is very happy about it.
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Old 12th October 2011, 06:33 PM   #16506
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http://www.filigrane.ru/Chumakov_Sto...earity_EAT.pdf

it works on a Mac with Google translate:
The analysis of the electroacoustic channel as a channel for information transfer.
A model of the influence of distortion components in auditory perception channel audio
of information.
Evaluate the effect of deterministic and stochastic nonlinear distortions
on the subjective perception of audio information.
The technique of measurement and the percentage for stochastic nonlinear
distortion power amplifiers, audio-frequency measurements based on feedback
intermodulation AMI (RIMD).
Presented and discussed results of the measurements and subjective assessment of quality
amplifier designed with a view to ensuring the requirements for the reverse
nonlinearity, and without such records.
Formulated quantitative eligibility criteria and the subjective perception of the measured parameters of the stochastic nonlinear electroacoustic tract.
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Old 12th October 2011, 07:13 PM   #16507
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Quote:
Originally Posted by QSerraTico_Tico View Post
The technique of measurement and the percentage for stochastic nonlinear
distortion power amplifiers, audio-frequency measurements based on feedback
intermodulation AMI (RIMD).
This translation may be misleading. RIMD means Reverse Intermodulation Distortion, and it is measured by injection of 2nd signal to the output. This is not about "feedback intermodulation".
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Old 12th October 2011, 07:31 PM   #16508
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Quote:
Originally Posted by PMA View Post
This translation may be misleading. RIMD means Reverse Intermodulation Distortion, and it is measured by injection of 2nd signal to the output. This is not about "feedback intermodulation".
complain with Google
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Old 12th October 2011, 07:43 PM   #16509
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Just clarifying. Google translation is usually useless. They failed to translate "obratnych", which means both reverse and feedback. Anyway, there is an english definition of RIMD in the text.
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Old 12th October 2011, 07:55 PM   #16510
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Sounds like IIM to me.
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