Prost
Scott,
Given the accuracy of those crooked shooting irons issued to soldiers at the time the tactics made sense.
However, even after proven outdated in the war between the Confederation and the Union they where also carried on into the age of the machine gun and precision field artillery by Generals so inflexible, they could not see how much the world had changed in 50 years.
The results where the appalling casualties of the first world war on all sides.
It is comforting to know that if people close their minds in Audio, the worst that happens is bad sound, not tens of thousands killed in one day.
But the underlying mindsets and failures are sadly of the same nature.
50 Years after THD has been shown useless we still measure THD.
Meanwhile other things that we know to matter are being ignored for as long.
Ciao T
Given the accuracy of those crooked shooting irons issued to soldiers at the time the tactics made sense.
However, even after proven outdated in the war between the Confederation and the Union they where also carried on into the age of the machine gun and precision field artillery by Generals so inflexible, they could not see how much the world had changed in 50 years.
The results where the appalling casualties of the first world war on all sides.
It is comforting to know that if people close their minds in Audio, the worst that happens is bad sound, not tens of thousands killed in one day.
But the underlying mindsets and failures are sadly of the same nature.
50 Years after THD has been shown useless we still measure THD.
Meanwhile other things that we know to matter are being ignored for as long.
Ciao T
Hi,
Sure archers did not, nor did musketeers shoot just straight, even in those days the sights had elevation build in.
Ciao T
Sure archers did not, nor did musketeers shoot just straight, even in those days the sights had elevation build in.
Niccolo Machiavelli in "The Prince" said:
Ciao T
Thorsten,
As far as I know Von Békésy examined the movement of the cochlear partition in human and animal cadavers. Through observation of silver particles scattered on Reissner's membrane, he presumed that this was similar to the movement of the basilar membrane.
So, what he was basically doing is looking at the mechanics of the inner ear, after preparation of samples. I don't dispute that this provided some new insights, such as the travelling waves in the cochlea, but it is research that took place over 50 years ago, and his findings have been questioned since, at least to some extent.
However, and this is not a detail, Von Békésy's research applied to prepared basilar membranes, and the ear is an active pick-up system. The basilar membrane shows considerably less frequency selectivity than either the inner hair cells or the single fibres of the auditory nerve.
In other words, even if Von B. found harmonics on the basilar membrane, it would be a stretch to translate this one on one to what comes out of an ear in vivo, as measured on the auditory nerve.
vac
Hi,
Considerable additional research backs the conclusions. Including work on distortion perception from Olson via D.E.L. Shorter to Geddes et all.
Of course, one may reject evidence contrary to ones beliefs, should one be so inclined....
Ciao T
Considerable additional research backs the conclusions. Including work on distortion perception from Olson via D.E.L. Shorter to Geddes et all.
Of course, one may reject evidence contrary to ones beliefs, should one be so inclined....
Ciao T
So?
References please?
Whether the figure is 5%, 10%, 25% or 30% does it make any material difference to the question - exactly what are you trying to establish with THD measurements of linear systems? When the ear is patently neither linear nor distortion free, does this make any sense? Or, are you saying that the ear is linear & distortion free?
And remember, these are all just hypotheses - read a 2010 paper for some other hypotheses http://igitur-archive.library.uu.nl/med/2011-0204-200555/Book Heerens de Ru EN.pdf
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reductio ad absurdum!
or just
absurdum!
or a more recent reference GUBU - GUBU is an acronym standing for grotesque, unbelievable, bizarre and unprecedented. GUBU - Wikipedia, the free encyclopedia
Again, you are so shackled to your belief system that the requirement to think about it is a threatening prospect & so you fail to see what's being said - reducing it to simplistic statements like above. Nobody is saying that low distortion isn't important - it's just not the complete picture & needs to be carefully qualified - the details might be important to achieving good sound, rather than the rather simplistic "flat frequency response" statement
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Thanks for that paper, jkeny. I was in quite desperate need for something like that. Always having wondered about the plain obviousness of the little experiment I've stated (among many others I tried in conjunction with it) I thought there MUST be some research on this somewhere, as it is so basic to any listening and musical experience...
There's a nice review of this in the AES preprint by Robinson and Hawksford (109th Convention, Los Angeles, 2000).
None of this is relevant to amplifiers, mind you, but if you're concerned with design of data compression systems like MP3, this is the kind of stuff which is needed to be taken into account.
None of this is relevant to amplifiers, mind you, but if you're concerned with design of data compression systems like MP3, this is the kind of stuff which is needed to be taken into account.
the role of an amplifier is not to replicate any distortion of the ear - if distortion in the ear is significant you only want it to happen once - in your own ears for which your brain's neural nets already are wired for
anyone serious about audio looks at the distortion products, IMD not "just THD" - the "THD, only THD" is a obnoxious Strawman being pushed here for rhetorical purposes - not to advance the discussion
the reason engineers like ultra low distortion (including IMD - which also inclues PIM) is it is a indicator of Linear Amplification - you know the old "straight wire with gain" rubric - maybe by itself it isn't the prime determinant of "audio quality" but it is part and parcel of a Linear response
it gets tiring pointing out that engineering in general does/has/continues to use all sorts of "dynamic" tests, steps, bursts, asymmetric waveforms - anyone know how old the BBC "Noise Fill" test is? – or actually look a (noninteger, logarithmic) multitone – particularly near the peaks that give “high crest factor” – the reason to search for sequences without the highest peaks is simply a S/N argument – higher average power over the course of the test
citing a paper that spends so much time on the "amplitude only fft" Strawman is really silly given the info that has been referenced so far in diyAudio on the subject
and now after trashing poor engineers who are claimed to be stuck with just the amplitude spectrum, only "infinite" sine waves, symmetrical, continuous signals - the last few pages has every one excited over 48 KHz soundcard measurements - because of the "innovative" pulse stimulus???
these really aren't arcane/unknown issues to serious audio designers that have been awake, reading Signal Theory books, JAES papers, patents, industry white papers by real experts, even the Audio Precision analyzer Manual
anyone serious about audio looks at the distortion products, IMD not "just THD" - the "THD, only THD" is a obnoxious Strawman being pushed here for rhetorical purposes - not to advance the discussion
the reason engineers like ultra low distortion (including IMD - which also inclues PIM) is it is a indicator of Linear Amplification - you know the old "straight wire with gain" rubric - maybe by itself it isn't the prime determinant of "audio quality" but it is part and parcel of a Linear response
it gets tiring pointing out that engineering in general does/has/continues to use all sorts of "dynamic" tests, steps, bursts, asymmetric waveforms - anyone know how old the BBC "Noise Fill" test is? – or actually look a (noninteger, logarithmic) multitone – particularly near the peaks that give “high crest factor” – the reason to search for sequences without the highest peaks is simply a S/N argument – higher average power over the course of the test
citing a paper that spends so much time on the "amplitude only fft" Strawman is really silly given the info that has been referenced so far in diyAudio on the subject
and now after trashing poor engineers who are claimed to be stuck with just the amplitude spectrum, only "infinite" sine waves, symmetrical, continuous signals - the last few pages has every one excited over 48 KHz soundcard measurements - because of the "innovative" pulse stimulus???
these really aren't arcane/unknown issues to serious audio designers that have been awake, reading Signal Theory books, JAES papers, patents, industry white papers by real experts, even the Audio Precision analyzer Manual
Thorsten,
I gave you some factual information about Von Bésésy's work, implying that the bar graph you showed is not what you make it out to be.
I can't have a serious discussion with you on the basis of remarks like the above. Distortion perception is something very different from the topic we are discussing: the blank statement that the human ear distorts 30% or more. You came out in favour of that statement, and I think it is a fallacy. As I pointed out, Von Bésésy's work is limited to the basilar membrane (or rather, from measurements on Reissner's membrane as a proxy).
As I mentioned in an earlier post, there are distortion products noticable in the auditory system, but this is not HD, but IMD in a complicated way. This distortion is audible. When two tones are presented to a subject, a third tone may be percieved (difference tone, cubic difference tones and derivatives).
This is the only kind of distortion generated by the ear itself I have been able to find in the vast literature on this topic (apart from the known non-linearities, which are not the kinds of distortion we are discussing here). Please inform me if you know otherwise, otherwise concede this point.
I think it is relevant to audio, as everything is that we can find out about the ear and auditory system. Therefore, for the benefit of others, I want to take away misconceptions you try to muscle in through discussion tactics.
To believe in the statement that the ear has high distortion, opens the door to other nonsensical ideas. For example, that THD does not matter and that 50 years of THD measurements and efforts to bring it down to 0.00008% have been futile.
So, let me finish with an analogy: the human eye and chromatic aberation. Any single lens system has chromatic aberation plus a number of other distortions, and so has the one in your eye. Yet, this is compensated for, so we don't percieve any. In response to John Curl's suggestion that the same might happen with the ear, you throw one of your other low balls. Completely unfounded. Because whatever distortions the ear produces, and whatever non-linearities are present, any able subject can distinguish distortion above a certain level, deviations from a flat FR, and many other fine differences.
In other words, whatever the shortcomings of the ear and auditory system are, we as human beings are finely tuned to percieve minute differences in sound stimuli. Something must compensate for these shortcomings, so I think John is exactly right.
vac
Nobody ever said it was - talk about strawman arguments!!
Anyway, time you & your "poor trashed engineers"should try & ignore all this side issue & get back to doing what you do only too well ....................trash JC!!
From the rules: ''diyAudio reserves the right to terminate accounts that over time have demonstrated a negative effect on the community.'' This account has a history for infractions about offensive posting, and unfortunately it goes to no better, demonstrably so by receiving reports on your last posts that got team examined today. Goodbye.
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