Great experiment, but here we are talking about an effect that is tied to the file not the hardware. That is with random playing of the two files through the same hardware the same one shows the impairment each time. As Waly points out you show an analog impairment not the bits or in other words the information contained in the file. Again, this is a very well thought out experiment.
AFAIK thumb drive memories run multi voltage level storage cells and are prone to noise on write and read processes with auto error detection/correction process ensuring correct data output/read.
Differing auto correction/processing activity could be a cause of "Logic Induced Distortion"....I have suggested this ages ago.
Dan.
Differing auto correction/processing activity could be a cause of "Logic Induced Distortion"....I have suggested this ages ago.
Dan.
Ah, the old blameshifting tactic (blame your -imagined in this case- adversory for your own wrongdoing) comes into play.
It simply doesn´t matter what you could or couldn´t not imagine, as i was only responding to your example (as cited and it was not about the same hardware).
And then you made something up; yeah as if i think about violation of.....
Maybe your obsession with "fighting" is the underlying problem. Just admit when you, as in this case, did something wrong, move on and try to think less about fighting but more about constructive discussion.
Ok, let's call it swimming in jello. Lots of effort and nearly zero outcome.
I'm sure you'll find even the subject of Bybee devices worth discussing, nitpicking about, and grasping at every straw to defend the indefensible.
Not for me, sorry, the entertainment part is gone. If you feel like defending each and every outrageous claim made in Audio that's your hobby, not mine.
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Likely obvious to many here. When Scott Wurcer talks about us arguing less around here and getting something done instead, I have to agree with that intent. Don't know why a self-proclaimed competent engineer can't get on board with the program.
Perhaps. It does seem to be more a thought exercise. What do you think about using headphones? I see too many uncontrollable variables otherwise.
Headphones are probably a good idea, unless there is a particular need to avoid them for a given experiment. Very near field monitoring might be okay too, again where possible.
Jakob's profile says audio development, I think he should get on and do something if he really wants to, I presume he can, he's not going to get a consensus here, he will get plenty of feedback!
Thats not what I said or meant. What I descriibed is two uncorrupted transfers of bit-identical data was arranged such as the bit pattern in the ASIO buffers and consequently the USB data blocks wasn't identical.
Say, USB block size is 4 and we have a sample sequence of "ABCD" looped forever. Thus, depending on the startpoint of the sequence we can have 4 different USB packets, ABCD, BCDA, CDAB and DABC. The bitstream to the actual DAC chip is bit-identical (otherwise a -110dBFS null would not be possible) but the USB data pattern is not, and the feedtrough of this was measured, actually a difference of feedthroughs. And the difference appears to be non-linear, this means the bit stream somehow managed to modulate the analog signal. Whenever I used the same USB packets (the null test) I didn't get a nonlinear residual, and also a clean residual when the sample block size was prime so that the disturbance -- just as any other non-correlated disturbance like mains hum - averages out (another null test).
The specific conditions depend on the objective of an experiment; if one is looking for differences important for the daily listening to loudspeakers, usage of headphones is most likely not such a good idea, as due to the many confounding variables transferability of results will be questionable.
If reproduction via headphones is the main area of interest it is obviously a different situation and if it is more about examining general mechanisms or audibility issues, usage of headphones can be the right/ultimate choice.
@DPH,
as said before, level of significance is always debatable, but as we already have overcome the quite senseless NHST-ritual, we know that it is no black and white decision criterion, can´t be matched in small trial experiments and that we should rely on replications before finally accepting results, it seems generally not as important as it was.
A bit different is the case of extraordinary claims and the extraordinary evidence needed, therefore i was more stubbornly asking about that.
@Waly,
main difference seems imo to be that quite a few members of the "nongolden ear" group obviously have clairvoyant abilities while i don´t .....
I thought the point was if two bit-identical playbacks on the same hardware could ever result in systematically different audio signals. Depends of the defintions of bit-identical, though. I would assume we agree that two different WAV files containing the same sequence of audio samples but one of them with a bunch of leading zeros is considered bit-identical as from the perspective of the actual DAC chip. From the view of the OS and the ASIO/USB packeting it is not bit-identical under these specific conditions.
But even one and the same identical WAV file may result in different packets depending of the history of the buffers. Assume a gapless playback list in foobar, once our test file starts it depends on what was played before how the packets transfered to the DAC device actually look like. This is also true for SPDIF packets, etc.
I fully agree that there is no -- and can't be any -- hidden information in the file *itself* (there was a huge and fruitless discussion in a german forum if a bit-identical file could sonically "remember" whether it was ripped from a CD using a notebook, one time on battery power and one time on mains power), but the actual playback process may contain variables that are not immediately obvious.
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It's not like OP is the official arbiter of audio electronics comparison. There is no need to seek an approval from OP.
Usually? You mean there are times we can be sure that it's possible to control all variables? Did that ever happen? If so, when and where?
Didn't imply he was, or say he needed to approve; but he did pose a question, so can get an answer.
Extraordinary claims would be audibility of immeasurable effects (or requiring absolutely heroic and contrived edge cases within the electronics realm) to start. I would say that it is pretty extraordinary for someone to claim audibility of effects that are way way outside of the ballpark range (let's say more than an order of magnitude) that has been established in the literature (where I openly acknowledge that I have a pretty incomplete view and there's a lot of the academic work in acoustics that falls into the traps given here: Why Most Published Research Findings Are False). Like every other human being, I use my old arbitrary and wholly internal form of Bayesian analysis. 😉
I expect some/much of the old literature to be overturned in time, but it's what we have now.
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