I am clearly confused based on a previous post (#660) of yours in this thread and perhaps others where you indicated a lot of this is old hat and settled. … Clearly my mistake.
Yes, clearly your mistake! You are confusing the proven scientific knowledge of how things work, the scientific laws and theories, with the practical usage of recording/reproduction equipment to create commercial audio content. It should go without saying that recording/reproduction equipment is not some sort of magic, it’s “technology”, which is the practical application of science and therefore it must follow those scientific laws/theories. The laws of electromagnetism were proven by James Clerk Maxwell in 1865, the theory of how electromagnetic (audio) signals behave in cables was set out by Oliver Heaviside around 1876 (entirely derived from Maxwell’s Laws) and all working cables made since then comply with this theory/laws, while the theorem of digital audio (digital communication in general) was proven in 1947 by Claude Shannon. So the science is old hat and settled but how we employ the technology derived from that science to create audio content is not settled, it is constantly evolving. For example, if we want to record a sound, then we have to setup a mic, connect it with a cable to a mic pre-amp and/or recorder, etc. This is the basic science, it was true the first day that electronic recording was invented, is just as true today, and the mic, cables and analogue signals they generate/transfer follow exactly the same laws/theories (although of course recorders these days follow the theory of digital rather than analogue). What is not necessarily the same is the number of mics we use, their type and placement, which is highly variable and dependent on the engineers’ choices, as are the choices when editing/mixing subsequently.
My family members think I am “obsessed”, and while I love my job, my hifi and music habits occupy a lot of my limited processing power.
“Obsessed” relative to what? Maybe your family members think you are obsessed relative to them, who have little interest in hifi but how many hours a week do you really spend on audio? I regularly spend around 50 hours a week, have had long periods when it was more like 70 hours a week, numerous weeks of over 80 hours and this is all pretty standard for many/most engineers. But more important than just the amount of time you spend, is what you spend that time doing. For example, just casually listening to music recordings and reading reviews for entertainment or training your listening skills, critically analysing recordings and studying the science, facts, techniques, methodologies and “art” of how recordings are made?
I compared at least four different designs of USB powered HD, from USB stick, to solid state SSD drive to USB drives with a physical disk that must be powered with via the bus. My experience is that there is a difference in sound, with the physical disks sounding flat compared to solid state drives …
Again, think about that for a minute! … It’s digital information, just zeroes and ones, so for there to be a difference in sound those zeroes and ones have to be different. Presumably, the “
physical disks sounding flat” was throughout the recording/s, not just once for a tiny fraction of a second? Therefore a huge number of bits would have to be different and not just any random bits but specific bits. We can measure the error rate and such a huge error rate simply doesn’t exist with USB, unless something is broken and even then, it would not be errors only of specific bits. Additionally, if the error rate were as high as you suggest all digital files would have a huge number of different bits (errors) and therefore USB would be unusable but clearly USB is not unusable, quite the opposite, it is used by countless millions of people.
So either: Something is seriously wrong with your testing methodology, you are experiencing a perceptual error (placebo) or you are suggesting some sort of unknown process that not only magically circumvents the design of HD or SS drives and of the USB protocol itself but also magically only affects audio files and only certain specific bits within audio files. And obviously, if you do circumvent the design of drives and the transfer protocol then how do you get any data at all out of the system, let alone a recognisable audio file? Therefore, unless you have some seriously robust evidence to support your suggestion, we can only rationally conclude one of the first two options must be the case!
For the record, I expected the HDD drives to sound the same or better with the Bluesound Node than the flash drive. They didn’t. They sounded worse. What is the opposite of “expectation bias”? Doubt bias?
This question indicates that you don’t know the basics of cognitive biases. Don’t you think it’s rather nonsensical to suppose and argue about something of which you don’t even know the basics, in a science discussion forum? FYI, the opposite of “expectation bias” in this context is still “expectation bias”, it’s just a different/opposite expectation, I’m not sure how that’s not self evident? Furthermore, “expectation bias” just predicts that if you know there’s a difference, in this case HDD vs SSD, then you might perceive a difference in sound (even though there isn’t one). It does not predict that you will definitely perceive a difference, what that difference will be if you do or how you personally will evaluate it, which is dependent on numerous factors, many of which are subconscious. Therefore, you stating that it couldn’t be expectation bias because of one single conscious expectation to the contrary, demonstrates both a fallacious argument and a lack of understanding of biases! Unfortunately though, this is a very common fallacy employed by audiophiles for decades to falsely dismiss cognitive bias/perceptual errors.
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