Objective proof the UpTone Regen ISO can improve a DAC's output(*)

[pkane2001]

6 hours ago, bibo01 said:

- Testing with static signal is pretty pointless, most of all to draw conclusions on SQ. One has to use dynamic signal at DAC output and confirm results with actual music too.

 

So, would you say that a measurement that shows that there is an actual AC noise linkage between the power supply of a DUT and a DAC is pointless, but listening to actual music using  an $8K power cord (as an example) is not?

 

[plissken]

6 hours ago, bibo01 said:

If I can add a couple of words on this matter...

 

- Testing gear has to be electrically isolated, one cannot risk to couple with DUT.

 

The AP is a piece of audio gear so the argument can be made it's meant to represent a typical setup. 

Quote

- Testing with static signal is pretty pointless, most of all to draw conclusions on SQ. One has to use dynamic signal at DAC output and confirm results with actual music too.

 

Alex was asked if he would do his own bias controlled evaluation. He said he would and then he disappeared from WBF immediately after Amir said he would fly out. I would still like to see this take place. 

 

Quote

- Following the above, I have shown measurements on original Regen where, depending on the DAC, Sound Quality was either improved or decreased. The DAC that was improved was not a $200 device - it was a $7000, well engineered device.  I am sure the same can be achieved with new IsoRegen.  

 

Link please I would like to read up. 

[lmitche]

33 minutes ago, plissken said:

 

Link please I would like to read up. 

Why would bib share the link? You are just going to "pliss" all over it!

[plissken]

8 hours ago, Speed Racer said:

 

...and here is the problem with just measuring. Sometimes what measures worse sounds better. Amir seems limited to just measuring which only part of the story. I would argue the least important part too. 

 

One is objective the other subjective. 

[lmitche]

28 minutes ago, plissken said:

 

One is objective the other subjective. 

The design of a testbed is subjective, as is the interpretation of test results.

[plissken]

17 minutes ago, lmitche said:

The design of a testbed is subjective, as is the interpretation of test results.

 

No, the design of the test bed is proven. Bottom line is that the UpTone improved the Modi 2 but the included SMPS is leaving some performance on the table for the Modi 2 and it's degrading the output off a DAC that otherwise was fine with out it. 

 

You are welcome to go and get your own ADC, ARTA, and setup your own testing environment and refute what Amir has done. Or end up with the same results and confirm it. 

[plissken]

1 hour ago, lmitche said:

Why would bib share the link? You are just going to "pliss" all over it!

 

Why would I 'pliss' all over it? If a well written, cogent argument is laid out why would I take issue with it. 

 

Now what HAS happened here in the past is people have posted papers and it's actually made my point for me. Just ask Jud and Jabbr. 

[tmtomh]

1 hour ago, lmitche said:

The design of a testbed is subjective, as is the interpretation of test results.

 

The use and abuse of "subjective" on these forums is quite something. 

 

I'm wondering if it might help things if we started using "repeatable" or "replicable" instead of "objective." If you can set up a test and replicate results, that's different than if you talk about, for example, your own listening impressions. 

[bibo01]

2 hours ago, plissken said:

Link please I would like to read up. 

You need to do a search at ASR in the original Regen test thread.

[pkane2001]

1 hour ago, lmitche said:

The design of a testbed is subjective, as is the interpretation of test results.

 

It's an objective result that ISO-R with Meanwell PS caused more AC noise in an otherwise very clean DAC output. It's an objective result that replacing Meanwell by a lab LPS removed this noise. Don't know what your interpretation is, but mine is that the inclusion of ISO-R with Meanwell PS can cause additional noise to be injected into the DAC.

 

Speculation about AC leakage loops formed by AP Analyzer is the subjective part in this discussion, provided with no objective evidence to back it up.

[bibo01]

2 hours ago, pkane2001 said:

 

So, would you say that a measurement that shows that there is an actual AC noise linkage between the power supply of a DUT and a DAC is pointless, but listening to actual music using  an $8K power cord (as an example) is not?

 

Nice logic.

[plissken]

2 minutes ago, pkane2001 said:

 

It's an objective result that ISO-R with Meanwell PS caused more AC noise in an otherwise very clean DAC output. It's an objective result that replacing Meanwell by a lab LPS removed this noise. Don't know what your interpretation is, but mine is that the inclusion of ISO-R with Meanwell PS can cause additional noise to be injected into the DAC.

 

I'm right there with you pkane. Not sure why we are have to deal with Alt-Facts in this thread. 

[pkane2001]

2 minutes ago, bibo01 said:

Nice logic.

Makes sense to me. You said static measurements are pointless, but listening to music is not. I gave you two counter examples to what you said.

[bibo01]

1 minute ago, pkane2001 said:

Makes sense to me. You said static measurements are pointless, but listening to music is not. I gave you two counter examples to what you said.

I said measuring dynamic signal and confirm results with music. It's possible to measure music too.

[pkane2001]

3 minutes ago, bibo01 said:

I said measuring dynamic signal and confirm results with music. It's possible to measure music too.

Got you.

[jabbr]

11 hours ago, plissken said:

 

Ok, but he's testing the unit AS SOLD by Uptone. 

 

You have to take the good with the bad. It helped make a poor DAC better and it made an otherwise good DAC poorer.

 

So now additional money beyond the $325 HAS to be spent not to get the problems with the included SMPS. Makes you wonder how much validation, if any, was done.  Why even include a 3rd party SMPS when you have all the design chops in house to build a straightforward linear 5v .5 amp power supply. That would cost $10 in a BOM. 

 

Well at least we are acknowledging the real issues. I don't know what a reasonable LPS would cost -- I use Chinese ones at are ~$100 (the r-core El-Cheapo) and I think that actually the transformer is a good part of the cost and good transformers are themselves a bit more than $10 -- I don't even know how the regen would work on a linear *unregulated* supply because I think it has its own onboard regulators. So really the PSU is a preregulator...

 

I do think that leakage current is probably more of an issue than PSU ripple! The Uptone supercap supply is bundled as an option so perhaps the recommendation is to go with that. 

 

The Meanwell is bundled because ? @Superdad feels the need to bundle something with the regen ... they aren't bad but I prefer the Inventus Medical grade series: https://www.digikey.com/product-detail/en/inventus-power/MWA020012B-10A/EPS499-ND/2764483 for low leakage current.

 

In any case the fact that these issues are being found to make a difference supports the idea that leakage current affects the DAC.

[jabbr]

28 minutes ago, pkane2001 said:

 

It's an objective result that ISO-R with Meanwell PS caused more AC noise in an otherwise very clean DAC output. It's an objective result that replacing Meanwell by a lab LPS removed this noise. Don't know what your interpretation is, but mine is that the inclusion of ISO-R with Meanwell PS can cause additional noise to be injected into the DAC.

 

Speculation about AC leakage loops formed by AP Analyzer is the subjective part in this discussion, provided with no objective evidence to back it up.

 

Lab power supplies are typically floating which reduce the issues with leakage currents (to the extent that the floating supply is not ground coupled by parasitic capacitance)

[plissken]

7 minutes ago, jabbr said:

 

Well at least we are acknowledging the real issues.

 

I have to again point out that it's not a manufacturer showing this but someone with some skepticism showing this. But somehow the messenger is getting some backlash over it. 

 

[lmitche]

11 minutes ago, jabbr said:

 

Lab power supplies are typically floating which reduce the issues with leakage currents (to the extent that the floating supply is not ground coupled by parasitic capacitance)

I can't think of a single person, of the 10 or so people I know that own a ISO REGEN, that uses anything but an LPS-1 for power,  Amir's assumption is that everyone chooses to purchase the ISO REGEN with a Meanwell is incorrect.  The Meanwell is an option at time of purchase. Perhaps Alex can tell us the the ratio of those that do so.

 

Again the design of the test is incorrect, or incomplete.

[plissken]

1 minute ago, lmitche said:

Again the design of the test is incorrect, or incomplete.

 

How so? 

[lmitche]

8 minutes ago, plissken said:

 

How so? 

Amir's test is based on "how sold". The ISO REGEN is sold two ways, with and without the Meanwell. With the Meanwell measures worse than with an LPS, that is expected, but as I said most people use an LPS or more specifically an LPS-1 to power the ISO REGEN.

 

Not testing with an LPS or LPS-1 is an error in the design of the test.

[pkane2001]

4 minutes ago, lmitche said:

I can't think of a single person, of the 10 or so people I know that own a ISO REGEN, that uses anything but an LPS-1 for power,  Amir's assumption is that everyone chooses to purchase the ISO REGEN with a Meanwell is incorrect.  The Meanwell is an option at time of purchase. Perhaps Alex can tell us the the ratio of those that do so.

 

Again the design of the test is incorrect, or incomplete.

 

It would be nice to know if LPS-1 is needed for proper ISO-R operation. A $325 ISO-R price tag is significantly different than the $655 bundle with LPS-1.

 

[mansr]

Just now, pkane2001 said:

It would be nice to know if LPS-1 is needed for proper ISO-R operation. A $325 ISO-R price tag is significantly different than the $655 bundle with LPS-1.

In the real world we call this "bait and switch."

[plissken]

Just now, lmitche said:

Amir's test is based on "how sold". The ISO REGEN is sold two ways, with and without the Meanwell. With the Meanwell measures worse than with an LPS, that is expected, but as I said most people use an LPS or more specifically an LPS-1 to power the ISO REGEN.

Great so we can agree:

 

1. Amir doesn't have a LPS-1

2. Amir does have a bench power supply

3. Amir does have a MeanWell power supply

4. Of the two supplies measured one introduces noise

5. None of the above rises to the definition of 'incorrect'

 

[plissken]

3 minutes ago, pkane2001 said:

 

It would be nice to know if LPS-1 is needed for proper ISO-R operation. A $325 ISO-R price tag is significantly different than the $655 bundle with LPS-1.

 

 

But that's ok. Since you will just need to pair with a $350 DAC and for $1000 you are at the ultimate in noise reduced, accurate, veil lifting, audio reproduction.