While browsing through old online magazine I came across 'Distortion hearing' article in September '57 wireless world.
https://www.americanradiohistory.com/Archive-Wireless-World/50s/Wireless-World-1957-09.pdf
It is on Page 35 of pdf file and printed page no is 435
Regards
https://www.americanradiohistory.com/Archive-Wireless-World/50s/Wireless-World-1957-09.pdf
It is on Page 35 of pdf file and printed page no is 435
Regards
Actually No, whilst speaker distortion is higher magnitude , our ears for some reason
seem to mask what that distortion is doing. Getting sources , attenuators and amplifiers free of time domain errors and distortions arising, and of course speakers from the same artifacts, is where most is to be achieved
Thanks for the link to the article on audio beyond 20kHz. Confirms what I suspected regarding importance of accurate waveforms - and why I think “transient perfect” speakers sound better. My 10F/RS225 FAST speakers with a simple 1st order passive crossover that resolves transients well just sound more natural and better than speakers with steep 2nd or 4th order LR filters.
Thanks for that! It's a complex article with a lot to take in, but gives some good info on masking, different portions of the audio spectrum and levels.
(there is also a nice article on the new SECAM color video system)
IM products are a particular concern as they crop up at difference and sum frequencies, and are present in vast numbers with complex music - I suspect the ears are most sensitive to distortions when there are complex signals with stereo imaging detail - with IM, not harmonic distortion, being the main mechanism to worry about.
It is however harder to meaningfully measure IM, as there are a myriad ways it could be done. I tend to favour sometime like a test with a spread of tones across the audio band and beyond arranged so all the sum/differences frequencies are unique - then the resultant spectrum is a fingerprint of the amps behaviour, and sum of the products defines the overall distortion figure w.r.t. the sum of the original tones.
It is however harder to meaningfully measure IM, as there are a myriad ways it could be done. I tend to favour sometime like a test with a spread of tones across the audio band and beyond arranged so all the sum/differences frequencies are unique - then the resultant spectrum is a fingerprint of the amps behaviour, and sum of the products defines the overall distortion figure w.r.t. the sum of the original tones.
Weird a 14+ years old thread comes out of hibernation once in a while !
In perspective, the old 20 to 20KHz useful bandwith or 0.1% thd paradigms are clearly too simplistic. On that same line, a thd test like 20 KHz - one of the most stringent yet according to Audio Precision - probably falls short of fully scoring a given device performance.
To me the only safe choice is to do the best in each component and then try to improve, with the understanding you are probably missing something.
Rodolfo
In perspective, the old 20 to 20KHz useful bandwith or 0.1% thd paradigms are clearly too simplistic. On that same line, a thd test like 20 KHz - one of the most stringent yet according to Audio Precision - probably falls short of fully scoring a given device performance.
To me the only safe choice is to do the best in each component and then try to improve, with the understanding you are probably missing something.
Rodolfo
The THD figure is a percentage and it does not tell anything about where and how distortion takes place. A more insightful way would be to investigate the amplifier's transfer function which should be in the form of a polynomial. The first term of such a polynomial is the DC offset voltage with the input set to zero, the second is the effective raw gain of the amplifier, and the other higher order terms determine the extent of intermodulation.
Other relevant points to consider are whether such a transfer polynomial is dependent on signal frequency. If this is true, the transfer function becomes a multivariate function. This means, if one chooses to go deeper and deeper into why and how distortion arises, one enters in a never ending maze.
Other relevant points to consider are whether such a transfer polynomial is dependent on signal frequency. If this is true, the transfer function becomes a multivariate function. This means, if one chooses to go deeper and deeper into why and how distortion arises, one enters in a never ending maze.
Knowledge of the individual harmonic amplitudes gives you much the same information as the polynomial. Harmonic distortion figures are reasonably well correlated with intermodulation figures, except for close spacing.
THD tells us something, because it sets a bound on harmonics and therefore on intermodulation. Two mistakes commonly made:
1. "THD tells us nothing" - this is foolishness dressed up to look like a higher form of wisdom. It is sometimes used to justify favouring high distortion amplifiers.
2. "Sufficiently low THD is enough" - this may be closer to the truth, but pursuing very low THD as a goal in itself is likely to lead to engineering compromises which degrade something else.
THD tells us something, because it sets a bound on harmonics and therefore on intermodulation. Two mistakes commonly made:
1. "THD tells us nothing" - this is foolishness dressed up to look like a higher form of wisdom. It is sometimes used to justify favouring high distortion amplifiers.
2. "Sufficiently low THD is enough" - this may be closer to the truth, but pursuing very low THD as a goal in itself is likely to lead to engineering compromises which degrade something else.
A personal disposition with the primary aim to impress others is corroborative of narcissism, which is, a delusion. The latter, prevents sufferers from realising their limitations and shortcomings, leading one to belief there is no need to work harder to improve.DF96 said:
Trying to impress is only a sign of immaturity. Accepting reality, and working hard to improve it, is the key to success.
Science is much too young to answer this threads title
Some studies has been made on the subject, but far from enough to give an answer. There arent even enough knowledge about our ability to hear or supress distortion to even formulate the question presisely. What is partly answered, is; "Do we know anything about our ability to hear, dinstinkt and suppress distortion"?
Some studies has been made on the subject, but far from enough to give an answer. There arent even enough knowledge about our ability to hear or supress distortion to even formulate the question presisely. What is partly answered, is; "Do we know anything about our ability to hear, dinstinkt and suppress distortion"?
A fraction of a percent of any form of "distortion" is not noticable to the normal human ear.
Notice, I said "normal human", not someone that claims to have the hearing of a canine, which they don't.
However, the insistance of these self-proclaimed alien beings with "superior hearing" have infiltrated the world and internet and spread their holy words as the religion that us mortals must adhere to and follow.
And if you allow them to convince you, you're eventually going to wind up being a crazy nut-brained fool of the never-ending struggle to find that pot of gold at the end of that rainbow.
If you're a reasonable, even picky type of human, you'll follow your own mind and ears, and wind up a much happier person.
Notice, I said "normal human", not someone that claims to have the hearing of a canine, which they don't.
However, the insistance of these self-proclaimed alien beings with "superior hearing" have infiltrated the world and internet and spread their holy words as the religion that us mortals must adhere to and follow.
And if you allow them to convince you, you're eventually going to wind up being a crazy nut-brained fool of the never-ending struggle to find that pot of gold at the end of that rainbow.
If you're a reasonable, even picky type of human, you'll follow your own mind and ears, and wind up a much happier person.
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