So, the eye plot published by Uptone Audio is supposed to illustrate what? ISO Regen breaking up leakage currents? Looks to me more like USB signal regeneration. That's exactly why I'd like to see more measurements. I want to understand what this gadget does and how it does it.
Who's buying the UpTone Audio ISO REGEN?
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So, the eye plot published by Uptone Audio is supposed to illustrate what? ISO Regen breaking up leakage currents? Looks to me more like USB signal regeneration. That's exactly why I'd like to see more measurements. I want to understand what this gadget does and how it does it.
The eye plot stands for itself, its obviously cleaner. It's a normal-mode measurement, just as any measurement made with an AP or dScope will be, so completely unable to give a clue about leakage currents.
When you start asking for common-mode noise measurements you might start to be taken seriously with your request. But fact is there aren't any standardized common-mode noise measurements yet. You'll need to specify things like loop impedance for example.
When you start asking for common-mode noise measurements you might start to be taken seriously with your request. But fact is there aren't any standardized common-mode noise measurements yet. You'll need to specify things like loop impedance for example.
Those are technical assessments all of which should be verified with instrumentation. We have no evidence that such instrumentation was made to confirm any of them.
I have two of them and they make no difference to my ears. Now what? Is your data more valid than mine? You see the issue? This is why we measure. It takes you and I out of the equation and gives us objective data to analyze which can be repeated and confirmed.
Here is one of the measurements I made of last generation product, the regular Regen:
First notice that our instrumentation is more than sensitive to find such differences.
Second and more importantly, more distortion products were added, not less. They are not of audible consequence but do invalidate our assumption that all of these devices do good in reducing noise and distortion. We perform measurements to confirm our understandings which may very well be faulty.
I know from conversations with the Regen team that they had no way to instrument the analog output of the DAC such as above and hence were in the dark that they generated extra distortion products. This is the danger in purchasing products from companies who won't bother confirming their (often lay) assumptions about how things work.
In this case, who says a cleaner USB signal is better? A strong USB signal conveys more energy to the DAC in its digital pulses. So if you are worried about bleed-through, you may not want a better signal. And further, we need to know the spectrum of that bleed-through which our DAC output analysis shows. The eye pattern as posted by Alex, not so much.
Bottom line is that more data is better than less. It lets us weed out the good implementations from bad.
So you argue that my request for jitter measurements cannot be taken seriously, because leakage currents are the main issue that ISO Regen is trying to solve. I'm OK with this. Then why publish a diagram showing improved edge timing that says nothing about leakage currents and everything about jitter?
You seem to have grasped the issue. Which is more than I can say for Amir
Does the eye diagram say 'everything about jitter' ? To me it doesn't, and I've read some of the technical background arguments about the Regen.
Perhaps explain why you see an eye diagram in the way you do?
Incidentally I agree with your first point - the eye diagram says nothing at all about common-mode noise.
You seem to have grasped the issue. Which is more than I can say for Amir
I'm glad we reaching some common ground
Very simply there is no effect, other than jitter, that digital data transmission errors, noise or distortion can have on analog output if the bits are not flipped. Jitter is it.
I'm glad we reaching some common ground
Me too
In terms of the normal-mode output (that which is typically measured) this is true. However in the real world the downstream kit is not 100% immune to common-mode noise. So even when the measurements indicate effective perfection, the SQ can suffer due to this noise which never shows up in a normal-mode measurement (coz its common-mode). Its the elephant in the room for audio quality which measurement-baters don't wish to notice.
Guy goes to visit his friend and notices that he is snapping his fingers. He asked him what he is doing. He said he is keeping pink elephants out. Friend asks how that is possible. He says, "you don't see any pink elephants, do you?"
Come back with some data you have personally gathered to confirm your theories. If you have no such data, then I guess pink elephants don't exist....
The "fruits of labour" seems to consist of posting forever on forums, than any effort spent verifying the the devices do audibly, what you say they do. Or objectively do the same. You have neither. Do you even have the eye pattern that Alex post about your product?
Also, exactly what is your role in the products you sell?
Ah, but you are switching context on me. We were talking about the eye pattern posted by Uptone. We agreed that the eye pattern is not an illustration of common mode noise rejection. My point was that this leaves jitter reduction as the only possible reason to show such a measurement, as that is the only way a better eye pattern can manifest itself at the output of a DAC. Do you disagree?
You have limited knowledge, and no data whatsoever that leakage current is a) there and b) dealt with in ISO Regen yet you are taking strong positions in this thread?
You don't think this is an objective measure that can be measured? If it is not measureable, how do we know it has been dealt with? And if it is measureable, what to make of the fact that such measurements are not made/posted?
Not quite - I'm saying that any normal-mode measurement is going to be insensitive to common-mode noise. Audio test equipment is designed like that in general.
Rejection of common-mode noise is not something I've talked much about, other than to say audio test equipment is fairly good at it. Audio (listening) gear generally is NOT good at rejecting it.
I disagree. A cleaner eye pattern I believe Swenson found resulted in lower power supply noise at the USB receiver PHY. Power supply noise can very easily translate into common-mode noise, just as easily as it could translate into jitter.
The DAC is invariant. We show measurement with and without. Here again is the spectrum of regular Regen vs nothing using iFi DAC:
We see that contrary to manufacturer assurances and our lay assumptions, the levels of distortions increased using Regen, not the other way around. This is why we measure.
'Strong' is entirely a figment of your own mind. I take the position of a scientist open to new observations - I note you've brought none. In science a new observation can overturn an earlier hypothesis. What I've been offering is my best fit hypothesis for the observations.
Sure I do - looks as though you've not been keeping up in this thread. Suggest digest all I've said here before asking questions which have been already dealt with.
Again I have alluded to this a bit earlier on.
Good news - if you consider that your measurements show that nothing shown has audible consequences, people will feel more push to listen and decide by themselves. It is what the overwhelming majority of our readers fortunately do - they look for measurements to please their technical conscience (or their wallet) and then buy by just listening in sighted conditions.
But yes more data is better than less. It would be great if someone could show other type of measurements that show correlation with audible effects.
Oh dear, your interest in my commercial endeavours is endearing - do you wish to apply for a position, pray tell?
People with APs need to demonstrate they know how to use them however before I would even grant an interview & so far you are not a suitable candidate.
Hopefully, if you listen to what Opus & others tell you & do your lessons well, you can be some day?
Guy goes to visit his friend and notices he is snapping his fingers. He asks him what he's doing. Says he is keeping black swans out of his living room. Guy asks how that's possible, since black swans don't exist. He says, they don't where you live in Europe mate, but in Aussie we have truck-loads of them.(1)
If you're going to try and create little aphorisms, at least lease try and avoid mistaking absence of evidence for evidence of absence.
853guy
(1) "Rara avis in terris nigroque simillima cygno." Juvenal, AD 82. Despite the black swan being used as a European metaphor for that which could not possibly exist, Dutch explorer Willem de Vlamingh made the first European recorded discovery of the Cygnus atratus when travelling to New Holland in 1697, overturning one-and-a-half millennia of "evidence" for the non-existence of black swans. I should add that this sort of evidence is only ever uncovered by people willing to venture outside their narrow world-view and their domain of 'expertise'.
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This is how our problems in audio start. A hypothesis is created about lack of fidelity. Even though the hypothesis is grounded in real technical terms, no attempt is made to confirm it either with measurements or controlled listening tests. Folks then skip to "fixing" the problem but once again, they do nothing as far as measurements/controlled listening test to see if the thing they thought they were fixing, is actually fixed.
Now you could surprise and impress us by showing any data that confirms the above. Without that, it is just pure advertising to sell products of the above type.
I am not smart enough to have created it 853 guy ( BTW, you forgot to say "Hello Amir" this time). It is an expression with real meaning that is used in conversations, mostly in corporate world. In this case, my great boss at Sony told me that story with respect to lawyers wanting to put all kinds of terms in contracts that never come true. I deleted the lawyer reference to make it more politically acceptable.
Just do a google on "pink elephant" and be mindful of people who confuse it with "elephant in the room." They are two seperate things. Here is an example: https://www.quora.com/What-is-the-meaning-of-the-phrase-the-pink-elephant-in-the-room
"Pink elephant - a drunken hallucination."
And another random one: https://english.stackexchange.com/questions/104243/what-does-the-pink-elephant-in-the-room-mean
"When your body is physically dependent on alcohol, you will hallucinate when you can't get more alcohol. Pink elephants are the stereotypical image of what drunks see when they they get the shakes and possible seizures from lack of booze."
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