During the wait in the elevator ?
(alternatively, the incubation period for the court-approved mental ward)
Rigid is a diplomatic way of putting it. That's like calling Hitler's Waffen SS "somewhat conservative".
Yet, I can't remember any conservative, by-the-numbers scientist who ever dreamt up anything new. That priviledge always seem to fall into the yard of wacos, nutcases, and dreamers.
The lack of simple grace of tolerance is appalingly lacking on this forum. On the other hand, we have enough wanna-be scientists with their THD analyzers, without which they obviously cannot function because they don't trust their own ears, and/or because they are actually hearing something that goes against the current views. If not for a few seasoned and proven people, all this would crumble to dust in just a few minutes due to bickering.
Yet, I can't remember any conservative, by-the-numbers scientist who ever dreamt up anything new. That priviledge always seem to fall into the yard of wacos, nutcases, and dreamers.
The lack of simple grace of tolerance is appalingly lacking on this forum. On the other hand, we have enough wanna-be scientists with their THD analyzers, without which they obviously cannot function because they don't trust their own ears, and/or because they are actually hearing something that goes against the current views. If not for a few seasoned and proven people, all this would crumble to dust in just a few minutes due to bickering.
Ed. You've said too much already.
What, airwolf? That was last year, no??You're dating yourself again
You've been spying on the cable thread??
Sheesh, fas42 and I agree on something..I must be incorrect!!
jn
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Fordism - Wikipedia, the free encyclopedia
(to my defense, mechanical students at tech universities are totally brainwashed with Ford yada yada)
You touch on something here: 1. and 2. are interrelated. The smooth nonlinearities that produce the one will entail the production of the other. Second harmonic distortion will produce sum and difference frequency energy when two pure tones are processed. Third harmonic will entail closer-in sidebands, 2f1 -f2, 2f2 - f1. So for example the popular IM test of 19kHz and 20kHz will produce 1kHz when it is a system with second harmonic distortion. This will be audible unless very small, however unlikely that input signal may be.
More likely: complex textures will have degrees of masking, but the ear-brain-mind may decode something amiss. Descriptions vary.
Anecdotally, I've found those who claim second doesn't bother them often listen to fairly simple textures. One esteemed speaker designer has a wall of CDs of female vocalists, most with a simple piano trio or such.
On IM: years ago an RF engineer wrote a fairly inflammatory article for Electronics World (UK). I sent an LTE (that I should have slept on), as did Self. In essence the writer said audio people were fools because they only talked about harmonic distortion and didn't look at IM. Besides being patently false---had this person never seen an Atkinson sidebar with IM measurements?---the tone of the article was the usual bashing of audio engineering as being naive at best (Self suggested that maybe he should write an RF article). But for those who had never considered IM, perhaps there was some motivation that was sensible, as for a single instrument (say) a harmonic distortion generator of a typically realizable sort will simply tend to change the timbre---that is, it will be heard as an effect comparable or identical to "linear" distortion.
I think it should be fairly obvious by now for those who can connect my dots that few of you have any idea about what you can detect or what your threshold of distortion(s) is/are. A few of you, and myself included who have long experience with both listening and testing can tell with some certainty the threshold is between .1 and .01% thd. That varies a lot with the harmonic structure and the speaker/headhpones used (their distortion).
As I have said a couple years before on this forum, you dont listen to just one piece of your system; You hear the entire system's distortion... even going back to the studio. If you or I want to be sure that the communications system is truely transparent, each stage needs to be very low thd/IM so the accumulated distortion remains below your threshold of detection. This is where i get my -100dB or .001% figure for components'design..... ten times better than we can detect. But this is not only for a single tone's distortion difference detection, but a multi-tone level.
When you take large piece of the system out, such as, Direct-to-Disc recording, you get a clue as to why we are never going to do anything except argue -- subjective/objective here. The distortion of the whole, complete process as what we hear is not low enough.
THx-RNMarsh
As I have said a couple years before on this forum, you dont listen to just one piece of your system; You hear the entire system's distortion... even going back to the studio. If you or I want to be sure that the communications system is truely transparent, each stage needs to be very low thd/IM so the accumulated distortion remains below your threshold of detection. This is where i get my -100dB or .001% figure for components'design..... ten times better than we can detect. But this is not only for a single tone's distortion difference detection, but a multi-tone level.
When you take large piece of the system out, such as, Direct-to-Disc recording, you get a clue as to why we are never going to do anything except argue -- subjective/objective here. The distortion of the whole, complete process as what we hear is not low enough.
THx-RNMarsh
A very few understand that THD is a marketing spec and don't try lumping everything together to demand a threshold which is meaningless.
What really goes on here, is that each of us contributes only part of the total understanding as to how we rate distortion. It reminds me of a group of college sophomores talking about the 'meaning of life'. '-)
For example, IM is one distortion product that comes from a non-linearity in the transfer process. It is related to harmonic distortion, but the ratio between the two changes with frequency, etc. SMPTE IM used to be the 'gold standard' for measuring nonlinear distortion, but it has been replaced by harmonic distortion in recent decades, especially when individual harmonics can be separated and evaluated.
CCIR (2 high frequency tone) IM is rather effective, but not ALWAYS. Sometimes one distortion measurement is best for a specific KIND of nonlinearity. For example, TIM is usually related to input stage nonlinearity and limiting. SMPTE is great for crossover distortion, two greatly divergent distortion sources.
What people usually don't realize is that LOWER ORDER harmonic distortion implies IM byproducts that are RELATED to the musical notes actually being played. IM is not completely independent of harmonic distortion, unless there is a real internal problem with the gain stage. That happens too, with 'exotic' solutions sometimes. Enough for now. '-)
For example, IM is one distortion product that comes from a non-linearity in the transfer process. It is related to harmonic distortion, but the ratio between the two changes with frequency, etc. SMPTE IM used to be the 'gold standard' for measuring nonlinear distortion, but it has been replaced by harmonic distortion in recent decades, especially when individual harmonics can be separated and evaluated.
CCIR (2 high frequency tone) IM is rather effective, but not ALWAYS. Sometimes one distortion measurement is best for a specific KIND of nonlinearity. For example, TIM is usually related to input stage nonlinearity and limiting. SMPTE is great for crossover distortion, two greatly divergent distortion sources.
What people usually don't realize is that LOWER ORDER harmonic distortion implies IM byproducts that are RELATED to the musical notes actually being played. IM is not completely independent of harmonic distortion, unless there is a real internal problem with the gain stage. That happens too, with 'exotic' solutions sometimes. Enough for now. '-)
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Of course it is used in marketing in a meaningless way. I am not using it as in marketing. You, SY, esp need to know your own best threshold and those conditions for it. From that you can determine what the thd/IM needs to be designed to for the whole system to be 'blameless'.
Multi-tone testing -- Harmonic and IM products are produced. Seems like the best way yet to test.... and run them thru the entire system would be a good thing to know and compare to your threshold.
THx-RNMarsh
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Multi-tone testing -- Harmonic and IM products are produced. Seems like the best way yet to test.... and run them thru the entire system would be a good thing to know and compare to your threshold.
THx-RNMarsh
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John is correct in that THD is a catch-all and that we use specific types of stimuli and interpretation methods to wring out different distortion mechanisms. Trying to talk about a "threshold" for something as broad in meaning as "THD" is not terribly useful.
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