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Testing audiophile claims and myths

Discussion in 'Sound Science' started by prog rock man, May 3, 2010.
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  1. AudioThief
    This reminds me of a discussion I had with my father some time back. Basically, he and his friend & colleague (both of whom are engineers) said something akin to - " The truth is something we agree upon". Now it might be a case of semantics, but I fundementally disagree with this stance. I believe that the truth is the truth no matter what us humans figure out about it. Now clearly, what we believe to be true at any given time is the best approximation of truth, but we must always be open to the truth being something else than what we currently believe is true.

    Anyways, again I am having some difficulties placing myself on the spectrum of objectivist - subjectivist. Here are my rough definitions based on some years reading on head-fi, reddit etc..


    - All DACs sound the same, this is a fact (given comptetent manufacturing/design)
    - All amplifiers sound the same, this is a fact (unless badly made/tube etc)
    - Headphones sound different, but its mainly just a matter of EQ
    - "Detail" is actually just treble heavy signature
    - Any headphone rig exceeding 600$ including amp and DAC is a matter of taste, not of quality (so for instance, HD650 cannot be beaten in a technical aspect unless you prefer a brighter signature, or more bass)
    - You can tell how a headphone sounds based on its measurements, any quality stated beyond that is simply "perceptions" and essentially disposable impressions.


    - Believes DACs sound slightly different, but with the differences being impactful - for instance adding a sense of space to recordings, lowering treble spikes, tighter bass response etc. (not measurable afaik?)
    - Believes amps sound different but even less so than DAC, except when speaking of electrostatic amplifiers, in which the differences seem to be viewed as more important than DACs
    - May or may not believe cables sound different
    - Believe a wide range of headphones deliver a wide range of different levels of quality, so for instance clearly there is a host of headphones performing strictly better (to their ears) than HD650, but not necessarily HD800. It seems most agree that its a matter of taste once you get to around HD800 and up.
    - Believes that measurements is only one part of the puzzle

    Now clearly, at least around these parts, objectivists and subjectivists seem to agree that the perceived differences are real. Then we have to ask ourselves, well why do we perceive these differences? Is there a difference in sound, or is it completely made up in our minds?

    This is interesting because to me, both stances seem reasonable. It makes completely sense to me that biases and expectations would sway the way I think of equipment. It also makes sense to me that those biases could make me hear something isn't actually there. For instance, looking back at it I remember going from my modi MB DAC to my Gustard X20 Pro and I felt it did EXACTLY what I hoped it would do - make the sound a tad bit more flat/even sounding and bigger overall sound. Thats a bit strange, isnt it? I expected it to do that, and it did that. Thats weird, that doesn't logically make sense. That sounds like a bias at work. At the same time, I can remember listening to my rig before purchasing and being annoyed several times at certain point in songs, at several different moments thinking that this is the one imperfection I want taken away. And once I did upgrade my DAC, after months of deliberation, I never once had any complaints. I really did find the rig to behave exactly like I wanted it, and I stopped looking for upgrades. So was I never annoyed with the sound in the first place, convincing myself that I needed to waste hundreds of dollars on a big box to take up desk space? Or was I in fact annoyed with the sound, then once the new DAC arrived, I just masterfully learned to simply ignore it to fool myself?

    I am looking at other aspects of my life, and I find that my view of the world would be wildly different if it turns out that my enjoyment of any experience was such a big subject of my biases that I am essentially never able to judge somethings quality without considering a host of other factors before it. When I buy a pair of shoes, I like to think that I am completely able to judge its comfort based on its comfort, not if its a 100$ adidas shoe or a 300$ adidas shoe.

    Earlier today, I sat outside bathing in the sun - I live in the city, close to a road with lots of traffic. I closed my eyes and listened to the cars driving by. I considered how hard it would be for me to recognize the sound of a semi trailer driving past if I didn't already know that semi trailers drive past the road that is there regularly - if I had no concept of where I even was, who knows what my mind told me that sound would be. A train? Some strange machine flying in space? Me being carried away rapidly past a factory? I can't help but consider that blind testing seems to be a weak sort of proof, but at the same time, clearly biases play in to a large degree also, especially in this community.

    It feels as if the truth is somewhere in between, its hard to say I am a strict objectivist because it just doesn't sit right with me that its all bias.
    CoryGillmore likes this.
  2. Fuzzy789
    How?, Diminishing returns is a thing a $400 IEM/Full size will be a night and day over a $60 one. While anything at $1200 is just minimal gains versus the $400 iem/full size, like your not missing much at all if your using a ER4XR on all aspects. I don't understand how that bias when overblowing the gains on "TOTL" gear is okay around allot audiophile circles, The only one in my view that deserves it title is stax but even then your not missing out much unless you need a headphone that costs more than my PC and on par with a used car...

    The only time cables help sound is if the IEM is output Independence sensitive which is common with BA based gear, the CFA andro is a more well known case

    Not to mention sound sigs are FR based if the driver is good enough you can EQ in the same sound sig. Hence i highly doubt the gains of 5 to 12 driver's to 1 to 4 driver in the multi BA area
    Last edited: Jul 7, 2019
  3. gregorio
    You reply is particularly interesting because it highlights some of the fundamental issues very well indeed. I'll break my response down into individual points but largely, they are all one and the same point:

    1. Commonly when it comes to audio, we have two basic sides to the scientific/rational approach of working out what the actual facts are: What is the observed evidence and what are the underlying scientific principles/facts involved. Then, we combine these two sides to arrive at an answer with a "level of confidence" (sometimes this can effectively be 100%, other times we're just talking about probabilities). Before we do this though, we also have to break down these two sides individually into confidence levels. What confidence do we have in the accuracy/reliability of the "observations" and what confidence do we have in the underlying scientific principles. For example, the two confidence level extremes as far as observations are concerned are generally: Sighted A/B or "impressions" tests (being the lowest confidence) and highly controlled laboratory double blind tests with a large sample size (being the highest confidence). On the scientific principles side, are we talking about one of two or more competing theories (low confidence) or are we talking about a proven/completely accepted scientific fact, such as a "law of physics" for example (unassailably high confidence)? We also need to have a confidence level in how the underlying scientific principles are being applied, their context. It's a very common audiophile marketing trick to correctly describe some scientific principle/fact but in practice it's actually nonsense because it's out of context and inapplicable. Taking this basic rational/scientific approach, what you believe ("could swear") you heard/perceived is almost worthless, as it's "observed evidence" with the very lowest reliability/confidence level. However, on the scientific principles side; electrostatic headphones have a very unusual power requirement compared to the vast majority of headphones (extremely high impedance and voltage swings). For this reason, differences between amplifiers' output characteristics (voltage and impedance for example) which would be inaudible on the vast majority of headphones, could be quite easily audible when using electrostatics (depending on the exact design of a particular set of electrostatics). So to start with, the underlying scientific principles indicate that there is (or could be) audible differences with your headphones and those amps and furthermore, it's entirely likely that a more powerful amp will drive a set of electrostatics more linearly/accurately (audibly so) than a lower powered amp. Therefore, although your observations constitute evidence of the lowest reliability, I am more inclined (though still not convinced) to accept them as accurate, because they closely align with the underlying scientific facts.

    2. This is a very good example of the opposite situation. The underlying scientific principles (and objective measurements of DACs) demonstrate that while there certainly are differences between DACs, provided they are competently designed for high fidelity, those differences are below (and typically way below) audibility under normal usage. So now, not only is your observed evidence of the lowest confidence level but it also contradicts the science/objective facts and therefore I have virtually no confidence in it whatsoever! :) Logically, if an observation contradicts the science/facts, then it needs to have the opposite, extremely high confidence, in order to be taken seriously (highly controlled, double blind, large sample size and repeatable for example).

    3. We keep returning to: What does "better" mean? For example, a set of headphones (or other equipment) which emphasises the bass would likely be perceived as "better" by anyone who has a preference for louder/more bass but if we define "better" as higher fidelity, then this set of headphones is actually worse. In other words, "better" has no meaning beyond a particular individual's preferences, so unless we define "better" more precisely and relate it to an audio property (rather than a perception) then we can only answer subjectively. Unfortunately, the common consequence of audiophiles not appreciating the difference between a perception and an audio property is that if something sounds "better" to them personally then it is better period, regardless of how we define "better". This is an obvious problem because "better" is most commonly defined as "higher fidelity" and therefore to many audiophiles "higher fidelity" and "better to them personally" is the same thing, leading them to blindly insist that equipment which is objectively, provably lower fidelity is actually higher fidelity. Vinyl verses CD is probably the most obvious example of this but there are several.

    4. Agreed.
    4a. This really is the heart of it all! What we perceive is, for virtually the entirety of our lives, our only experience of reality and also, if there is a difference between what we perceive and reality, the vast majority of the time it makes relatively little practical difference to our lives, so we can (and naturally do) just accept our perception as reality. Therefore, "coming to terms" with our perception not being reality (and sometimes being extremely different to reality) is really not required most of the time and it if is, it's a bitter pill to swallow. Very few of us can just easily override/discard the experience of a lifetime, it takes time and requires a lot of counter-experience, for example comparing our perception to reality by using objective measurements and performing blind tests and, doing this repeatedly over time. It's worth it though, it really is an eye opener. For some people (and many audiophiles fall into this category), it's too bitter a pill to swallow and in some extreme cases, it's a pill they won't even accept exists, despite the obvious evidence: For example, we all know our vision is a perception which doesn't entirely represent reality, we don't perceive a complete loss of vision every second or so (when we blink), our brain creates a perception with the blanks filled in and, we all know that because perception is at least partially just an invention of the brain that our vision can be easily fooled, we've all seen a variety of optical illusions which prove this but for most of us, most of the time, it makes relatively little difference, it's little more than a curiosity. However, there are exceptions, visual art (paintings, etc.) for example is largely/entirely based on visual illusion/perception. Likewise, if we just want to enjoy listening to music, then it also doesn't really make much practical difference but if we're going to analyse/discuss music (or it's recording and reproduction) then it makes a huge difference because music is also almost entirely based on perception/illusion! In fact, music is itself a perception, it doesn't really exist, it entirely depends on the brain's propensity to emphasise sonic patterns and create relationships between them. That's why we don't even have a proper definition of "music", there are various different definitions but there are exceptions to all of them. Probably the most surprising and obvious example of the brain completely changing the sense of hearing to create a perception is the McGurk Effect, it's well worth the 3.5 minutes if you haven't seen it before.

    4b. It works both ways. A well designed blind test tries to focus on what we're actually hearing by eliminating biases, regardless of which way they are working. Of course, an individual can effectively lie, for example by selecting random answers when in fact they can identify a difference and that is why we have more confidence in the results of controlled tests with a larger/wider sample size. It's also worth noting that biases are relatively complex things. Firstly, there a lot of different biases, Secondly, our perception is virtually never under the influence of just one of them, Thirdly, many of these biases are subconscious and Lastly, there's no set priority between them, the brain is constantly evaluating them, making a judgement/perception for each event and again, doing this subconsciously. A common fallacy inadvertently employed by many audiophiles is along the lines of: "I didn't expect to hear a difference but was surprised that I did and this proves that the difference I heard was not due to (expectation) bias". This is a fallacy because it ignores all the other biases (including other expectation biases) of which they were not consciously aware and which typically have more influence over our perception than the biases we are aware of!

    5. Again, glad it helped. Yes, it does take time but it's time I enjoy spending more than the time I spend going round in circles, trying to respond logically to completely illogical, false assertions of facts. Having said that, it perhaps doesn't take as much time as you might imagine, as for several years I was a university lecturer in audio engineering/music technology and so have already thought at length how to explain how audio works and the perception of it to those just starting the journey.

  4. bigshot
    Again... I'll repeat myself. Subjectivist and Objectivist has nothing to do with specific opinions about home audio. It's a PROCESS for determining the truth. Subjectivists trust their own perception and feelings. Objectivists trust verifiable facts that can be tested.

    Look at your own post critically here. You dearly want the truth to be somewhere in the middle. You've had several lengthy answers that pointed out things that you hadn't considered, yet none of that has affected what you are saying. This post is pretty much the same as your first post on this subject. Is your bias preventing you from incorporating solid information from other people? THAT is why we try to eliminate bias. The way to define what is real is to take input from others and look for patterns. We don't try to create the patterns in our own head and then go on to prove them. That's what we do when we conduct controlled listening tests and work out the odds by averaging samples. The chips fall where they fall and we figure out the truth from that. It's an ongoing process of refining that is never completed. Logical analysis is a skill that becomes stronger from regular use.

    I would explain point by point the problems in your specific examples representing both subjective and objective "beliefs on reddit", but you threw out so much wrongness in one bullet point list, it would take three Gregorios to have the patience to go through it all.

    You can't learn without taking input, testing it, and putting it into proper context. Critical thinking is how we do that. That is why for technical things, objective analysis is better than blindly trusting subjective impressions.

    Instead of trying to find out who is right, start thinking critically for yourself. Take one achievable subject and discuss it with us, Stay on point and see how we approach it and the facts we use to support our case. You'll understand what objective analysis is better by doing it than by letting reddit cut to the chase and just tell you the conclusion. Objectivism is all about HOW YOU REACH CONCLUSIONS... not the conclusions themselves.
    Last edited: Jul 7, 2019
    Fuzzy789 likes this.
  5. sander99
    Question (and maybe an answer to AudioThief's doubts concerning blind testing):
    Would it be a good idea to do the following, or can there be any problems with this from a scientific perspective:
    First do extensive sighted listening to the things you want to compare, take as much time as you like. Get "familiar" with the sound, and try to find "suspected differences" and specific audio fragments with wich you seem to hear these "suspected differences". Then do a well set up double blind ABX test using those specific audio fragments. Only if you can confirm the "suspected differences" in this test they can become "accepted differences".
    In fact, I am wondering if this approach should not even be considered mandatory before concluding that there is no difference (or rather: I think this approach would raise the level of confidence that there is no difference). (Certain differences are maybe only audible with specific kinds of audio fragments, and not by all people. If you just do an double blind ABX test with a "random group of people" and a "randomly chosen set of audio/music fragments" and just look at the "statistical relevance" of the deviation from 50% correct score you could get to a false conclusion if for example none of the audio/music fragments was suitable to hear the difference.)
    [Edit: I just now discovered the following thread:
    Maybe this is already discussed there? I found the thread because I wanted to refer to the example of Swedisch Radio where - as someone claimed - important differences were missed in a blind test. Differences that someone else immidiately picked up in a "sighted test". Hence my idea to first do sighted listening to find "suspected differences". (I don't know about what all the real facts in the Swedish Radio case are, still have to look at that.)]
    Last edited: Jul 7, 2019
  6. bigshot
    What would the purpose of the sighted listening be? To train yourself to hear differences? Because if there isn't a difference, and you can prove that conclusively in a blind, level matched, direct A/B switched test, there's nothing to train yourself to hear, all you would be doing is convincing yourself that differences exist that don't actually exist.

    You'll note that I said "blind, level matched, direct A/B switched". There are reasons for each one of those controls. Blind testing reduces the impact of bias. Level matching avoids the human tendency to think louder sounds automatically have better sound quality. Direct A/B switching helps avoid auditory memory from fading between samples. You can google why these controls are important. These are all well established techniques with solid reasons behind them. They can help you discern differences that are smaller than can be discerned in uncontrolled tests. You can go ahead and throw them all out and do a sloppy test first, but it isn't going to change the results of the controlled test. And you're not going to hear things you couldn't hear in the controlled test either. The controls are already guaranteeing that you are getting the most precise and accurate comparison possible- free from bias , perceptual error and memory problems. Why would a test with bias, perceptual error and memory lapses give you a more accurate result?
    Last edited: Jul 7, 2019
  7. sander99
    We crossed posts here, see my edit under my previous post.
  8. bigshot
    Feel free to discuss here. It's more on topic than the rest of the stuff in the comments lately. You also might want to look at the first post in the thread. It has a section on controlled testing and why it's important and examples of tests that have been conducted.

    The only thing to avoid is throwing out too many specific areas to discuss at once. That inevitably leads to chaos. Just take it one point at a time and help keep the discussion focused.
    Last edited: Jul 7, 2019
  9. bigshot
    The important thing to remember about listening tests is that they are not intended to detect all differences, just AUDIBLE ones. There can be differences that are measurable, but not audible. That may be important from a theoretical point of view, but not from a practical one. We are looking for differences that will impact our systems when we are listening to music in our living rooms. The average controlled listening test with tones detects differences that are an order of magnitude smaller than anything that would make a difference when you're listening to Beethoven on the couch. There is such a thing as good enough. Too many people chase down rabbit holes of absolutism. Most differences you read about in audiophile forums are completely irrelevant to real world music listening. You have to make an effort to learn what the numbers actually sound like to really understand. There are a couple of good AES demonstrations in my sig file if you are interested.
    Last edited: Jul 7, 2019
  10. sander99
    Ok, I didn't know that. Note I would never accept a difference heard in a non-blind test as prove that there is a difference, I only considered the possibility that some differences might be easier found with a sighted test.
    Oh, I absolutely agree. We are basically in the same camp I think. My intension was just to have "something to give" to the people who criticise or doubt controlled blind testing, without giving up the conrolled blind test as a final demand to prove audible differences.
  11. bigshot
    The truth doesn’t always lie halfway between opposing opinions. I’ve learned that over the years. I had to unlearn all that stuff they taught kids on the Smurfs!
  12. castleofargh Contributor
    the way I see it, your suggestion would try to reassure people who believe their own sighted impressions but doubt blind tests. and you consider that it could help setup a more relevant test. maybe that would help on occasion but as it would for the wrong reasons, IDK if it's desirable.
    a blind test can have mistakes and will have limitations. but a sighted test is always a flawed test. lack of control, extra variables, nothing done to limit personal biases and preconceptions, how could that ever count as a conclusive experience and support the idea of finding audible differences? that would be a pretty dangerous game where we validate something we should not, for the sake of convincing someone. but once we have given such value to sighted experience, why would those people let us take that back? they were already in a position of trusting themselves and not the blind test, and now we would tell them that their sighted impressions are legit enough to condition how and when we should do a blind test. if I was on their side, I would conclude that sighted impressions are legit and that we need blind tests even less than before. ^_^

    to find test signals or conditions favorable to spot differences, think of that as engineering. we want to test something and some people with know how and the right mind, will be in charge of creating the tool that does it. they may come up with lousy solutions full of flaws, or they may build a very clever test, humans will be humans. but consider that science doesn't consist of one test and we're done. ideally, people with proper qualifications would set up and administer the test. ideally, we'd have other scientists look at the test and try to find errors(with some fame when they succeed, so the incentive is there). ideally, the guys making the experiments would share as much information as they can, and report potential issues if they find them, instead of trying to achieve a result they want at any price. ideally, other people would try to replicate the experience and check if the results agree with the first one.
    when the entire science machine is in action, the likelihood for a test to do what it was supposed to do will dramatically increase along with the confidence in the results and the quality of the interpretation of those results.
    on the other hand, when none of this is applied, well, the results may or may not be informative, the conclusion may be an overreach, and I wouldn't blame anybody for not placing 100% confidence in them. :wink: IMO even the first post in this thread has conclusions that go too far compared to the experiments described and their results.

    once you start to consider things not in truth and falsehood but as statistics, degrees of confidence, and conditional truth, the facts become more compact, specific, and I find them easier to digest.
  13. AudioThief
    Thank you for this great post.

    I have gotten a much better idea, and my perceptions have indeed changed quite drastically since entering this sub forum a couple of days ago. In large part because of your great way of explaining things, gregorio.

    @bigshot I have no idea why you are being rude, I think I've come across as completely honest as to what is my core belief entering this sub, and trying to understand/get it explained. I am looking for truth, nothing more nothing less. I'm sorry that I'm too stupid to understand it as quick as you'd like me to, I guess.

    I think I got what I came for from Gregorio.. I'll keep lurking, thanks for the enlightenment.
  14. bigshot
    We had an earthquake in my neighborhood recently. I was watching the news and they had the seismologists from the USGS on TV and one of them answered a question by saying, "Earthquakes were much simpler back when we didn't have so much data." That made me laugh, but it's true. More data may be more complicated, but you're closer to the truth too.

    I'm not being rude at all. I'm asking you to look at your own biases. You have biases. I have biases. They are as plain as the noses on our faces to everyone but us. It isn't rude to point out that you might have human failings just like me and the rest of the human population.

    Subjectivists get mad at objectivists because they honestly believe that they can control their biases and make an honest effort to simply look for the truth. But I'm sorry. No human can do that without the proper tools. Bias, placebo, cherry picking, slips in logic... all these things operate below your conscious level. You are operating on bias and making illogical decisions every single minute of every day. If you didn't, it would take you hours to make every small decision you make in a typical day.

    Feeling insulted is proof that you aren't being totally free of investing your ego into this. I didn't call you stupid. I said that I told you something and it didn't seem to register with you. I said that you got a lot of new input but after going through it your original premise didn't change in the least. I suggested that you seem to prefer to tread a line between the two concepts. Is that not a true statement?

    All I was doing was pointing out bias. Feel free to point mine out! I am aware of my bias. I use bias where it's helpful, but if I am looking for an objective fact, I use objective tools to eliminate it. When I go to do a test to determine if one amp sounds different from another I go to great pains to control my ability to express preference by making the choices blind, and I negate my perceptual error by level matching and direct switching. I analyze my results using critical thinking and logic. That is how I know I'm getting closer to the truth. I deny myself a chance to have a preference. What I want to believe is completely irrelevant to the truth, so I make an effort to remove it from the equation. Subjectivists make no effort at all. That's why their results are "impressions" not "facts".

    Objectivism is a process, not a destination. I can't emphasize that enough. It doesn't mean all amps sound the same. And it doesn't mean cables don't matter. I would be happy to be found wrong on both of those things. It wouldn't be an insult to me because evidence that proves I am wrong about it puts me a step closer to the truth,... and it's a gold plated invitation to a whole new line of inquiry. If you can do that, you're doing me a favor. But to do that, you are going to have to apply the same stringent controls to your test that I do with mine.

    I take the time to puzzle things out because I want to understand how they work. I don't want to rely on one group or another to make my mind up for me. These aren't baseball teams, they are processes for discerning the truth. As an objectivist, if I'm wrong, that is the best thing that can happen because it's an opportunity to learn.

    Hopefully, this clarification will help you understand what I'm saying a little better.
    Last edited: Jul 7, 2019
  15. KeithEmo
    I'm seeing a major flaw here in terms of how the idea of "subjective vs objective" is being conflated with the difference between blind and sighted tests.
    Doing a double blind test does NOT ensure you of getting objective results...
    All a blind test does is to avoid one specific sort of bias - a false positive based on expectation bias.
    For one thing, if you have an expectation bias NOT to hear a difference between two devices, a simple blind or abx test will do nothing to eliminate it.
    For another thing, a blind test doesn't eliminate purely subjective responses; for example, even in a blind test, a subject might PREFER the sound of a device with more distortion.
    (And, even if you're supposedly testing for "whether they hear a difference or not" they may still apply a subjective standard to reporting "tiny differences" or "significant differences".)

    There is a classic example of "visual bias" that is often described in psychology textbooks...
    A well-prepared steak is divided into two halves - and one half is dyed bright green with an odorless tasteless food dye.
    When subjects are invited to compare a green piece of steak to a normal looking piece, with their eyes closed, they routinely report no difference (proving the dye has no effect on taste).
    But, when invited to sample pieces, and allowed to see what they're eating, subjects consistently report that the green steak doesn't taste good.
    This clearly demonstrates some sort of bias to percieve green steak as "bad" (almost certainly because we've been taught to associate that color with "spoiled meat").
    HOWEVER, this is NOT a matter of "subjective vs objective"... (which would suggest something based on "opinion or expectation).
    Even when the subjects know that the steak is identical, and have no conscious expectation or opinion that they will taste different, they STILL perceive a difference.
    It is in fact a demonstration that, due the complex way in which our rbains are wired, input from one sense may affect how we interpret input from a different sense.
    We actually, OBJECTIVELY, experience the taste of the steak differently when we see a green color associated with it - and an MRI will show a different sensory response in our brain.

    To me it seems like an exact parallel if a certain audiophile finds that a "big impressive speaker" sounds better - but only when he or she can see those "non-audible attributes"....
    - or "one with a big impressive price tag"
    - or "one with better specs"
    (something "we imagine we hear because we expect to hear it" is quite different from "a subjective evaluation of something"...)

    I would also agree that I personally prefer to know whether what I'm hearing is being influenced by this sort of bias or not.
    Therefore, at least as a starting point, being able to determine how various devices sound while avoiding various common types of bias is certainly useful...
    However, I DO NOT believe that the terms "subjective" and "objective" apply here.

    The proper way to phrase the situation would be that "a blind test will rule out most positive expectation biases due to recognizing or seeing the product".

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