Really wrong. Apparently you don’t actually know what expectation bias is.
Expectation bias isn’t in your conscious mind, and you can’t control it. You don’t even know what your expectation bias is - even if you think you do.
Saying you can control or compensate for it is just another audiophile myth/crutch to back up biased listening results.
Yet another baseless statement. @Sheldon_Stokes summarised what I attempted to say earlier: you cannot design and build electronics without science, mathematics and measurements. Even if listening tests were to reveal something any adjustments would be measured and understood.
So it wasn’t just me then…
Wow…this is an eye-opener for me
I suspect that linking this discussion to archimago will simply add fuel to those who want to fan flames (and that’s on both sides of the debate)! I remember contributing to this question very early on. I would never have guessed that it would have exploded the way it has.
Tim, I am full of questions??? Now I am diving in to this digital world. At heart I love math and my logic is simple but in the analog world I can hear the differences. An example would be changing a phono cartridge out. In some cases its huge. Graphs give me true answers too. I looked at THD, IM, and output using Ohms law for guidance too. But after a few months of reading about digital hardware I found myself buying products from so called experts without looking at math. I guess I needed Archimago to get me back on track. I guess I made a few mistakes and I want eveyone else to learn from mine! Too late for me but not for others.
But Bill, you would be hearing your own reproduction of the sound! If what you want worked, then you could save yourself a fortune by having someone with a $1,000,000 set up just email you a sound clip for you to listen to on your phone…
@Magnus
I’d like to go back to that post again and kindly ask you, if you’d differentiate between electronics and loudspeakers/rooms - you’re correcting your speakers and room acoustics, using measurements, after all.
You likely studied Floyd E. Toole’s book Sound Reproduction Loudspeakers and Rooms, where it’s the quintessence, that the limited set of possible measurements do very clearly show, how something will sound.
We’re looking at a lifetime of meticulous scientific work to prove that.
If you didn’t, I’d highly recommend it.
If you also had a chance to look into psychoacoustic research, you’d likely come to the conclusion, that a good portion of measurable electronic’s distortion characteristics are imperceptible to the auditory system, since they are several orders of magnitude smaller, than with electroacoustic devices.
Consequentially, there seems to be quite some hard evidence in favour of the “objectivist measurement camp”.
Most subjectivist audiophiles wouldn’t fall for equivalent marketing blah, when buying other technical appliances.
Why is that so?
Too many emotions, maybe, clouding the minds.
Peace to everybody,
Marin
To quote someone: “There are things you can measure that you can’t hear, and there are things you can hear that can’t be measured”.
There is no proof that everything we hear can be measured, which means all so called “proofs” about measurements with regards to what we hear is based on an assumption. Besides, if you have a reasonable transparent system, its not at all hard to hear difference between a Raspberry 3/4 as transport and a transport like opticalRendu or Sotm sms-200 ultra.
To sum it up: the only way to determine audible differences is to use your ear (yes, its that simple 
)
Here is a HiFi News lab report on a Project Stream Box S2 Ultra.
There was a measured 20db improvement in the jitter spectra of some DACs using it compared to the output of a pc. And virtually no improvement in the case of other DACs. So, I don’t think anyone, especially those who claim to have a technical approach to hifi, should generalize about these matters. And they certainly shouldn’t claim that all USB outputs are equal, because that is not true. Interestingly the S2 Ultra is based on a Pi, but the designer has gone to considerable lengths to clean up the USB output of the Pi, which you can read about here.
If someone were to say something just wrong like that, someone would be sure to remain anonymous!
I’m not saying this is wrong. Especially the first part is proven. The second part though… You cannot base such a conclusion on anecdotical evidence. If you want to use a human as measurement device, which in itself is perfectly fine, you need to conduct a double blind test. If you can then proof with statistical significance that the test group can hear things we cannot measure (yet), then I agree with this statement. Until then, I’m quite sceptical…
Yes, but only if I were to depend on fallible human ears! Being me, though, I would be much more likely to run them into a computer and compare analyses. That way we could see exactly what the distortions are that makes the poster think one sounds “better”.
When in doubt, measure with equipment.
As I have just pointed out in my previous post, it is perfectly possible to measure a 20dB difference in the jitter of some DACs depending on which USB source they are connected to. How can you doubt that this is possible?
I’m sorry, but I’ve lost the thread of your argument. We were talking about jitter from the USB port of a Raspberry Pi, to a modern DAC. I don’t see that the test you pointed to addresses that. Without knowing more about the unspecified “PC” used in that “lab report”, I don’t even see how to even treat that as evidence of anything in particular.
Do you dispute the measurements? Do you think they are incorrect? In what way? Have you any of your own? What bit of science says that all DACs behave identically with all USB sources? The measurements are from an extremely well respected reviewer with decades of experience. You evidently didn’t read the post from John Westlake listing some of the weaknesses of the Pi architecture, so here it is in full.
“Basically its weakness are all based on Clock Phase Noise (Jitter) and local PSU noise (which directly impacts the Jitter performance) and also the resultant local RF emissions:-
The USB HUB / LAN IC is clocked by the CM3 SoC which has significantly higher jitter then an external Clock oscillator. More detrimental is that fact that clock phase noise is heavily correlated with the SoC software processing – resulting in Data correlated jitter.
The USB HUB / LAN IC PLL clock circuits are powered from the switching supply rail that also powers the SoC Memory, so as data is “processed” though the memory this causes modulation of the PSu Rail directly correlated with the Data patterns which then modulates the critical PLL in the USB HUB / LAN which is used as our USB “source” via this noisy PSU rail.
As one would expect little care has been taken with the quality of the 5V rail for USB DAC power – in fact its really pretty poor by “Audio” standards.
There are multiple “free running” switching regulators on the RPi PCB – whose clocks are not related to the USB clock Rate so there switching products are free to induced multiple / complex RF and Ground noise spurie in the system.
I could list more weakness, but you can start to appreciate the “Deficiencies” (not unexpected) of the simple Pi3”
I did indeed read the post, the entire thread, in fact.
First, about the “lab report”: I don’t “dispute the measurements”, but the documentation of the experimental design does indeed seem to be incomplete, so I’m not sure what he’s proving with them. In any case, this would seem to have nothing to do with measurements of a standard Raspberry Pi 3B+, which I thought this thread was about.
Then, about Westlake’s post: just parenthetically, I think this list of grievances by John Westlake, about the standard Pi, is more relevant to DACs powered by the master side of the USB connection. But even there, he talks about such concepts as “Audio” standards. Which are what? And how evidence-based are they? One might wonder if the proposed “fixes” are really more about propitiating the more clueless audio reviewers, than about actually making a useful improvement. More about bowing to the requirements of audio mythology than actually doing something important.
Again, Westlake offers no evidence, no measurements, showing that his improvements make a significant difference. It’s just argumentation. Hypotheses. And of course he has an ax to grind, a product to sell. I’m not saying he’s lying, just pointing out that it’s in his interest to argue that his product is somehow better for its purpose than the unimproved and much less expensive Pi (sales of which will not enrich him). Since we have no head-to-head measurements of the two, it’s an unproven hypothesis, I’d think.
If people wan’t to believe that measurements from Amir and Archimago tells everything about how it sounds, than they are free to do so. But notice the emphasis on “believe” because there is no proof involved. And thats one of the things I dislike about measurement discussions, some seem to think its all hard science vs bias-influenced listening, but as long as there is no proof that everything we hear can be measured its nothing but a theory at best.
Another thing: how many times have we read something like this from measurement descriptions: “there is a peak at 50Hz compared to XXX, but its not audible so nothing to worry about”. Not audible for whom and in what system? Because lets get one thing clear, what is audible or not depends a great deal on the HiFi system, room acoustics and even the listener.
I have the RME ADI-2 DAC (which does measure well), and I compared it to the Chord Qutest. I liked both, but they don’t sound the same. The treble is different, and Chord Qutest have a little wider (but less homogeneous) sound stage. Can someone point me to what difference in Amir’s measurements shows this? Nope, there is none, but they still do sound different
To you.
So much of what we hear is in our individual minds, it makes little sense to compare two pieces of equipment with any one person’s ears and brain. That’s why objective controlled measurement is so important.
In fairness, RME have been making studio grade audio interfaces that are designed to be connected to noisey powerful workstation class computers for a long time. I wouldnt expect anything less from them 
OTOH, with a less expertly designed DAC, your mileage may vary - alot!