Topic: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

There is now a "ADI 2 PRO" on the Diffmaker loop back Didier Brest test on  Gearslutz.
(https://www.gearslutz.com/board/gear-sh … er-52.html)             

The result in this test should correlate well with sound pureness.
Unfortunately it turned out very disappointing.

It is below my cheap now discontinued "Mackie Onyx Blackjack".
(I use the Mackie for playing a midi keyboard instrument.)

/Göran Nilsson

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

And what makes you believe these measurement results should be taken for serious? I learned: Doing measurements is not easy at all and needs a lot of experience.

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

This is a very easy test. You just connect out to in on your interface and record your result in a DAW.

I have heard no argumet against this test more than it not is corrected for frequency nonlinearyty.

Didier Brest wants more tests of the same interfaces so you can do it youself and upload.
Try it with the most linear filters. (DS sharp ?)
I have done it 4 times with other interfaces. I am waiting for my "ADI 2 pro AE" to come tomorrow.

Mybee I will send it back ?

/Göran Nilsson

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

RME also had great problems with the "babyface"
wich is the worst interface ever in this test!

And now this ?
Strange !

/Göran Nilsson

5 (edited by Randyman... 2018-03-21 18:04:53)

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

Let your ears be the judge.  I don't buy into the validity of DiffMaker as it directly relates to perceived audio quality.  Even in the GS thread itself - you will find many that love converters that score "worse" than other converters they ditched.

If you can't make a good capture and a good mix with a 'modest' converter (say a Digi002), then I really don't think the converters are to blame...

But it's up to you in the end smile

MADIface-XT+ARC / 3x HDSP MADI / ADI648
2x SSL Alphalink MADI AX
2x Multiface / 2x Digiface /2x ADI8

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

I paid 1800 EURO for my ADI 2 pro AE (I am waiting for it)
but I paid less then 200 EURO for the Mackie.

And the Mackie is better so of course you can make a good
capture and a good mix with a 'modest' (Mackie) converter.

Also remember:
there is no sound differences between converters in double blind tests !

But if you use it for mastering with hardware effects and several passes
the "ADI 2 pro will" degrade the mix (that is just what this test shows).
And this is of course audible.

/Göran Nilsson

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

kegn51 wrote:

I paid 1800 EURO for my ADI 2 pro AE (I am waiting for it)
but I paid less then 200 EURO for the Mackie.

And the Mackie is better so of course you can make a good
capture and a good mix with a 'modest' (Mackie) converter.

Also remember:
there is no sound differences between converters in double blind tests !

But if you use it for mastering with hardware effects and several passes
the "ADI 2 pro will" degrade the mix (that is just what this test shows).
And this is of course audible.

/Göran Nilsson

I doubt it! I mean I doubt that the ADI pro has these issues.

Vincent, Amsterdam
https://soundcloud.com/thesecretworld
Babyface pro fs, HDSP9652+ADI-8AE, HDSP9632

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

I did not dig very deeply into this test method, but what I did find out with some experimenting is how disproportionately large the influence of even minute phase shift turns out to be for the resulting "difference" - even if the files as such are otherwise absolutely identical. Depending on the sample rate, it can be very difficult to align two wave forms well enough to lead to maximum cancellation, even "half a sample" can make a significant difference to the value of this "measurement". My personal conclusion is that this test is simply no way to realiably determine a converter's audio quality. Returning the ADI-2 simply because of this figure may be a mistake. Trust you ears - and our published specifications, which are the ones that count, and whose results will not be determined by otherwise irrelevant factors like small phase shifts between DA and AD conversion, which may lead to a result of questionable value...

I wonder why no one has ever tried this test by feeding converter A's DA into the AD of converter B and vice versa, and then comparing - and wondering what the hell that result actually means... :-P

Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

9 (edited by ramses 2018-03-21 22:18:09)

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

From what I read / understand ~1-2y ago nobody really knew how this tool works internally,
so its not proven in any way, whether the results have any relevance / importance.
And I think the situation did not change since then.

You know how easy it is to attract people with a tool and a storyline... Especially if the tool delivers cool results that show that your not so expensive hardware now suddenly is better than the more expensive one. This is the right material for forum heros to debate things to death wink Besides of this it generates a lot of clicks. Which is nice for the server owner, if he is sponsored based on the amount of clicks. Therefore nobody has a real reason to stand up and tell "stop that shit!" or to make a valid analysis / proof of concept, that this data has a real meaning wink

I can only recommend, to not believe simply in numbers, especially if its not clear whether the program / the algorithms
behind it are correct or without knowing if they are bugfree and how they should be interpreted.

I really think better trust your own ears than to believe in tools and people who have no clue what they are doing /
measuring and are at the end only "consumer" of a tool, that they didn't design, write and understand.

It looks more to me that these folks are writing an agenda of their own. Of course they feel important  managing and interpreting all these "valueable" test results wink And the more people believe in this, the more additional people they attract and the more influence they can take on the not so skeptical consumer wink

It makes no sense to me, that some proven studio hardware of all sudden now shall be regarded as bad,
only because of a "questionable" tool.

BR
Ramses
X10SRi-F, E5-1650v4, Win10Pro20H2, Cub11Pro, UFX+, XTC, 12Mic, ADI-2 Pro FS R BE, RayDAT

10 (edited by pianopictures 2018-03-22 13:06:33)

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

To me that tests look interesting. I'm not in position to technically debate on their quality. I can't be sure one don't have some agenda behind it, nor the opposite. But I was interested in reading the comments, some are very reasonable on both sides. What that tests say is that for that particular method of testing some do better, some do worse. That's it and nothing more. I would feel fine about other methods of testing too.

And I would not be blindly angry at them if my more expensive hardware do worse than some cheaper ones in their particular test. That can be many reasons for that, like, the test technologies involved, human mistake factor, other variables (wires, connectors, electricity, grounding, etc.), some agenda, so on, and finally, poor engineering and cheap components behind the brand name (no implications here).

Also the feature they test is not the topmost important one for many people, including myself. Although for many it is.

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

pianopictures wrote:

Also the feature they test is not the topmost important one for many people, including myself. Although for many it is.

Which exact "feature" is this, how would you even call it? "Nullablity"?

The main issue I see is that the one factor that possibly has the greatest influence on this result (more than level matching), namely the timing offset (or phase difference) between DA and AD conversion of an individual unit, says nothing whatsoever about the actual reproduction quality of either of the two conversion paths. If there are differences in timing (e.g. on sub-sample level) that the test software can not compensate for absolutely 100%, then the result will be false and of no value at all, and the lack of exact time alignment appears like a fault of the converter or audio device, which it isn't. It really is as simple as that. To get anywhere near the required precision for time alignment of files, they would have to be oversampled internally multiple times, and I don't know if that is the case.


Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

12 (edited by pianopictures 2018-03-22 00:36:48)

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

I would call it "exactness" maybe, lol?

Yes, you are definitely right about timing. It means it is really hard to align with both recording and later comparison. Maybe some tests are just more "lucky" in this regards. It would help to do the sampling at a highest possible rates. Also would be great to implement some sub-sample delay in analog connection for several passes. Crazy.

Again, I'm speaking out of my mind thinking about reverse polarity null comparison, I did not dive deep into how their method works, actually don't want really, prefer others to do so.

13

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

kegn51 wrote:

The result in this test should correlate well with sound pureness.

Says who?

kegn51 wrote:

Unfortunately it turned out very disappointing. It is below my cheap now discontinued "Mackie Onyx Blackjack". (I use the Mackie for playing a midi keyboard instrument.)

The theory that Diffmaker's results have anything to do with 'sound accuracy' was already proven to be wrong. You just gave another example, where a unit that has noise and THD and whatever figures magnitudes worse than the ADI-2 Pro is claimed to be better. Why doesn't that open your eyes?

Critics are completely right that the maintainer of the list publishes uncertified and as such completely invalid 'test' results. Someone added data of the ADI-2 Pro. You know how many options the ADI-2 Pro has to process sound, and in how many menus these can be hidden? The only way to do a reliable test is to reset the unit before doing it, and I won't trust anyone to do so unless I stand beside him, and also verify he hasn't touched the B/T knobs anymore after that!

Now let's see what the filter options of the ADI-2 Pro reveal. I have a feeling that we finally see a simple example of how wrong the claimed meaning of DiffMaker's results are.

Regards
Matthias Carstens
RME

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

Yes frequency nonlinearity and phase shift seem to be the main cause.
And it is both hard and expensive to get these filters really REALLY good ? right ??

The test measures how well one pass of loopBack preserves the "mix".
In a mastering situation you may have several of these passes.

Before Mr Didier Brest started his maraton series of never ending
acumulation of rather dubius data there was this AMS who made several passes and
there it was a clear audiable difference between interfaces (high end better).
Gearslutz deleted AMS. (I hope I remember everything right now.)

Mr Brest now don't use The Diffmaker software (which was presented on an AES meeting)
but does his own calculation in Mathlab. But he presents the values from diffmaker also.
His method is not scientifically acknowledged as I understand it.

I will probably keep my ADI 2 pro AE (very good reviews from everywhere).

There are many  "A's DA into the AD of converter B" result in that infinite list.
From high end DACs To high end ADs with very very good results.

For example:----------------------------------------------------------------------
MOTU 828mkII ---> RME Fireface 400, 2 tests: MOTU or RME clock (MusicManic)
0,3 dB (L), 0,5 dB (R) Corr Depth: 24,5 dB (L), 26,3 dB (R) Difference: -44.1 dBFS (L), -45.3dBFS (R)

and the other way

RME Fireface 400 ---> MOTU 828mkII, 2 tests: RME or MOTU clock (MusicManic)
5,1 dB (L), 5,2 dB (R) Corr Depth: 35,1 dB (L), 36,7 dB (R) Difference: -54.7 dBFS (L), -55.7dBFS (R)

Maybee the RME AD is better than the RME DAC here?--------------------------------------

There is really no audiable differenses between converters. But yes you can hear the different
filters (very little). I guess that RME's problem is the DAC-filter (the CD player brickwall filter).
People also say that RME sounds clear in a harsh way.


/Göran Nilsson

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

Once more: It is not easy to do audio measurements properly. You need to be experienced. It is very easy to make mistakes. You just proved it yourself.

I recommend to forget Mr. Brest and his list completely. There is no proof that it is reliable in any respect. And Gearslutz is not a good place for discussing measurement methods and results anyway...

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

New test results for the ADI 2 pro is coming out.

Filters:
Slow_In  Slow_Out

ADM: -1sec, 0,351dB (L), 0,344dB (R)..Corr Depth: 33,6 dB (L), 35,2 dB (R) Difference: -52.4 dBFS (L), -53.5 dBFS (R)
Matlab: -1.000113818 s 0.3521 dB (L), 0.3453 dB (R) Difference: -52.8 dBFS (L), -54.3 dBFS (R)

These are acceptable numbers for the 1600 EURO price.

Old numbers not so good:
SD_Sharp_In  SD_Sharp_Out
ADM: -1sec, 0,366dB (L), 0,357dB (R)..Corr Depth: 33,6 dB (L), 35,3 dB (R) Difference: -43.2 dBFS (L), -44.6 dBFS (R)
Matlab: -1.000125149 s, 0.3521 dB (L), 0.3504 dB (R) Difference: -44.5 dBFS (L), -45.5 dBFS (R)

Everything now indicate that RME has to just tweek their slow filters to get still better results.

/Göran Nilsson

17 (edited by ramses 2018-03-22 11:24:17)

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

kegn51 wrote:

People also say that RME sounds clear in a harsh way.
/Göran Nilsson

I tested the ADI-2 Pro against the Accuphase DAC-40 in an E-600 Class-A with B&W 803D3 speakers in the past
and now the ADI-2 DAC with the same setup.

There is no harsh sound in any way. It has the same excellent sound quality plus IMHO a little bit more resolution in depth so that singer appear to be a little bit more separated from the band if the mix supports this.

My review, setup and use cases you can see here: https://www.tonstudio-forum.de/blog/ind … her-EN-DE/

kegn51 wrote:

People also say
/Göran Nilsson

People have different ears and tastes. They listen in different rooms. And they are using different combinations of amps and speakers.

Then you never know with what kind of DAC those people selected the other components like amp and speakers for their room so that it sounds nice to their ears.

This makes it extremely difficult to base a purchase decision on other peoples opineons. You don't know the people, their skill, their taste, their methodology to perform tests and the surrounding conditions like room, amp, speakers.

Best advice is that you test it in your environment and take care to make blind or double blind tests.

BR
Ramses
X10SRi-F, E5-1650v4, Win10Pro20H2, Cub11Pro, UFX+, XTC, 12Mic, ADI-2 Pro FS R BE, RayDAT

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

I will listen to the AD converter and compare it to my other interfaces.
In fact I can do that (most people can not do that because they don't have that kind of setup).

But I don't have any means to compare DACs. And I don't bother so much about DACs. I dont even know
how that should be done. I have good AudioVector speakers in a treated room so that part is OK
but no way to change DAC during listning.

And yes (people say) "'the ADI 2 pro' has excellent sound quality plus a little bit more resolution"
and is not as harsh as the other RMEs.

/Göran Nilsson

19 (edited by ramses 2018-03-22 12:56:40)

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

kegn51 wrote:

And yes (people say) "'the ADI 2 pro' has excellent sound quality plus a little bit more resolution"
and is not as harsh as the other RMEs.
/Göran Nilsson

Hi Göran,

you are right, this is my personal opinion based on my tests. This part I can't take over for you, thats cleary your job to validate it in your environment.

I only put this example in the hope that it brings the discussion back to a level that everybody can more easily agree upon, to better judge a device based on own tests.

My review is simply to give you some illustrated examples / ideas, what benefits you can achieve with the ADI-2 DAC
and that it is "at minimum" on par (for my ears even slightly better) with a DAC of a renowned vendor of high end HiFi products like Accuphase.

Some ideas for your testing .. I could use 2 free ADAT ports of RME recording devices
- 1 optical SPDIF to the Accu
- 1 ADAT out to the ADI-2 DAC (as it support the 1st 2 channels out of the ADAT stream up to 192 kHz)
With the remote control of the E-600 I could switch between Analog IN (from ADI-2 DAC) and
digital IN (from built-in DAC-40 module).
If you should have an AV receiver or another amp, you might also have analog and digital inputs
and perhaps also a remote control. Otherwise you need to control this on the other end i.e.
with a recording interface from RME with at least 2 outputs that support ADAT and optical SPDIF.
Then you can use the ARC USB with a ~5m USB cable and then you can control it by selecting snapshots via ARC USB.

BTW .. a good and flexible device for testing could i.e. be the Digiface USB. There you can even set all 4 ADAT Outputs to optical SPDIF to test up to 4 different DACs if your Amp / Pre-Amp should support so many analog inputs.

BR
Ramses
X10SRi-F, E5-1650v4, Win10Pro20H2, Cub11Pro, UFX+, XTC, 12Mic, ADI-2 Pro FS R BE, RayDAT

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

Yes that should be possible here too.

But how to set the loudness the same and
within 0.1 dBC ?

/Göran Nilsson

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

kegn51 wrote:

Yes that should be possible here too.

But how to set the loudness the same and
within 0.1 dBC ?

/Göran Nilsson

Sorry, what do you mean by "the same" ?
I don't know of any other DAC with a dynamic loudness function to compare this RME uniq feature with another device.

And I think this would be the wrong methodology anyway.

1st objective is to compare DACs without any Loudness, PEQ setting, simply neutral settings.

The dynamic loudness is simply a unique feature of the RME DAC which is very useful for me when turning down the volume as you do not have the typical effect of "loss" in the sound (of Bass and Treble) if the volume decreases to low listening levels.

The factory settings were for the described setup perfect.

If I listen at the usual listening level then I turn the DAC to -10dB, where its still neutral and adjust the power on the Amp.

When I turn the volume down on the ADI-2 DAC, then the loudness automatically increases over a range of 20dB, from -10dB to -30dB to reach its customizeable maximum value at -30dB (and lower volumes).
The customization of the max Loudness boost is from +1dB up to +10dB, adjustable in 0.5 dB increments.

The rest works fully automated.

You can assign one of the customizeable keys on the remote control of the ADI-2 DAC to i.e. turn on and off the loudness effect so that you can cross check the difference at any time.

BR
Ramses
X10SRi-F, E5-1650v4, Win10Pro20H2, Cub11Pro, UFX+, XTC, 12Mic, ADI-2 Pro FS R BE, RayDAT

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

I mean the SPL level from the Speakers must be the same when you switch DAC.

/Göran

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

kegn51 wrote:

The test measures how well one pass of loopBack preserves the "mix".

pianopictures wrote:

I would call it "exactness" maybe, lol?


There are very well established criteria to determine this. They are called frequency response, signal/noise ratio, and distortion.

The quality of the results of this loopback test (not the quality of the tested converter) depends to a large extent on how how well the software can compensate for deviations in timing and level between DA and AD, both of which have nothing at all to do with the actual conversion quality, they simply do not matter. A testing procedure which largely relies on eradicating issues affecting the result which that method itself introduces can hardly be considered reliable in my opinion. To be fair, I'm not sure the Diffmaker software was ever designed for this DA-AD loop test.

Neither DA nor AD conveter work any differently in such a loop test, they do the exact same thing as in a normal setup. This means the technical specifications (a.k.a conversion quality) remain exactly the same. If any converter were as bad as some of these test results suggest, that would also apply to any AD conversion process, not just to the loop, and the above mentioned technical specifications would have to be terrible.

Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

24 (edited by ramses 2018-03-22 14:35:28)

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

kegn51 wrote:

I mean the SPL level from the Speakers must be the same when you switch DAC.
/Göran

Yes, its doable by ear comparison.

BR
Ramses
X10SRi-F, E5-1650v4, Win10Pro20H2, Cub11Pro, UFX+, XTC, 12Mic, ADI-2 Pro FS R BE, RayDAT

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

ramses wrote:
kegn51 wrote:

I mean the SPL level from the Speakers must be the same when you switch DAC.
/Göran

Yes, its doable by ear comparison.


You could also use a test tone and some kind of SPL measuring app on your phone - doesn't even matter if the result is exact in absolute terms...

By the way, the timing/phase issue that has a significant influence on the loop test result is of no relevance at all in a listening test.

If you can, get someone else to switch without telling you which converter you are hearing, to avoid expectation bias.


Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

MC wrote:
kegn51 wrote:

The result in this test should correlate well with sound pureness.

Says who?

MC you're right! I've mentioned it many times in that topic: The test IS flawed, users without a clue of how to gainstage are randomly recording one cards input in another cards output. Then Didier "calculates"the "difference" and then "corrects"it with mathlab

why this test is flawed?

1. different input and output latency
2. different signal levesl
3. different RFI enviroments (desktop /laptop /USB PSU/Battery, ground no ground etc)
4. random outputs "recorded" on other gears input

If you want to do anything meaningful you're better of calibrating your IO loop in REW or use an RTA with an impulse

(Post edited for correct quote levels - RME Support)

www.analoguemastering.com

27 (edited by pianopictures 2018-03-22 19:32:58)

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

Would be interesting to compare not the direct loop from one device, but use two similar devices, out to in (not clocked). Should the results be the same or different?

Another question is are the outputs-inputs of a particular device required to be precisely calibrated to have the same sensitivity/gain? It would have no sense for real life situation if the outputs are slightly hotter or not, also the inputs are normally have to be dialed up to a specific task every time.

28

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

I am not a specialist with Diffmaker nor have I ever tried it personally (when I wanted to do that years ago it just kept crashing on start-up already), so I have to rely on the available information found in the GS thread.

Diffmaker is said to do a null test between the original file and the newly recorded file. This nulling is done automatically and with sub-sample accuracy, otherwise it woudn't work at all (at 44.1 the chances are like zero to have both files sample-accurate).

Diffmaker's results have people wondering since years what is wrong with it, as its over-exagerated results seem to have an internal weighting that often contradicts other measurement methods.

Maybe the filters of the ADI-2 Pro now easily explain it all. When Diffmaker is doing the nulling, parts of the file are still not nulled - because any analog and digital signal path includes phase shift, at the lower end and the higher end. This phase shift is inaudible, a proven fact.

With the ADI-2 Pro you have phase-linear and minimum phase filters at your disposal, on both AD and DA side freely selectable. Now we see that the most transparent and less damaging filters SD Sharp (which have said phase shift) deliver bad results, while the intransparent, treble reducing and partly aliasing causing linear-phase filters are 'measured' as superior. These results indicate that Diffmaker ist completely centered on the full nulling with a weighting that is unusable in real-world, and will even indicate the opposite of what is true.

kegn51 wrote:

New test results for the ADI 2 pro is coming out.

Filters:
Slow_In  Slow_Out

ADM: -1sec, 0,351dB (L), 0,344dB (R)..Corr Depth: 33,6 dB (L), 35,2 dB (R) Difference: -52.4 dBFS (L), -53.5 dBFS (R)
Matlab: -1.000113818 s 0.3521 dB (L), 0.3453 dB (R) Difference: -52.8 dBFS (L), -54.3 dBFS (R)

These are acceptable numbers for the 1600 EURO price.

Old numbers not so good:
SD_Sharp_In  SD_Sharp_Out
ADM: -1sec, 0,366dB (L), 0,357dB (R)..Corr Depth: 33,6 dB (L), 35,3 dB (R) Difference: -43.2 dBFS (L), -44.6 dBFS (R)
Matlab: -1.000125149 s, 0.3521 dB (L), 0.3504 dB (R) Difference: -44.5 dBFS (L), -45.5 dBFS (R)

Everything now indicate that RME has to just tweek their slow filters to get still better results.

The penny hasn't dropped it seems, so I give you a simple example:

kegn51 wrote:

The test measures how well one pass of loopBack preserves the "mix". In a mastering situation you may have several of these passes.

Do exactly that. Connect input to output at same ref levels with everything EQ etc turned off, then re-record one file 10 times in a loop. A 10 second sample is enough. Use SD Sharp on AD and DA. I guarantee that you will have a very hard time to hear a difference between the original and the 10 pass file, if you manage that at all.

Please note that intentionally the DA has a bit lower level than the AD, to prevent overloads in loopback applications. The difference is small (around 0.1 dB), but after 10 times it will be more than one dB, so you need to normalize or manually correct the level of the 10 pass file to be able to reliably listen for sound differences.

Now do the same test with the Slow or NOS filters (phase linear). Treble is lost already on the first pass! After 10 passes you get a dull sound, all glitter removed.

Thinking about it that would also be a perfect reason for the developers of this project to abandon it. Nulling can't work with analog/digital conversion and all the filters that are needed and unavoidable.

It also opens the way for another theory: units that show extreme high Diffmaker scores are lucky to have the DA phase shift be compensated by an inverse AD phase shift. They will get super scores for something inaudible, while the real sound quality based on SNR, THD and frequency response is not, or only a little involved in that score.

Hmmm, I spent too much time with this stuff again...

Regards
Matthias Carstens
RME

29 (edited by mjfe87 2018-03-23 17:55:00)

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

MC wrote:

I won't trust anyone to do so unless I stand beside him, and also verify he hasn't touched the B/T knobs anymore after that!

Or her! wink

Seriously though, this thread is why I love RME -- they refuse to get bogged down in the marketing language of GS and almost all other audio companies.

It seems clear that sample inaccuracy alone renders the infamous GS loopback thread flawed.

We're *very* happy with our new ADI-2 Pro that's just arrived in the post.  Except for the fact it doesn't sit flat on the desk!  One of the rubber feet must be thicker than the others?

Eastwood Records
www.eastwoodrecords.co.uk

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

The "Gearslutz List" has been updated with several diffrent filter combinations:

RME ADI-2 Pro, balanced out to balanced in (LesC)
Sharp DA - Sharp AD: 0.4 dB (L), 0.4 dB (R)..Corr Depth: 33,6 dB (L), 35,2 dB (R) Difference*: -53.9 dBFS (L), -55.2 dBFS (R)
Slow DA - Slow AD: 0.4 dB (L), 0.3 dB (R)..Corr Depth: 33,6 dB (L), 35,2 dB (R) Difference: -52.8 dBFS (L), -54.3 dBFS (R)
SD Sharp DA - SD Sharp AD: 0.4 dB (L), 0.4 dB (R)..Corr Depth: 33,6 dB (L), 35,3 dB (R) Difference*: -44.5 dBFS (L), -45.5 dBFS (R)
SD Slow DA - SD slow AD: 0.3 dB (L), 0.3 dB (R)..Corr Depth: 33,6 dB (L), 35,2 dB (R) Difference*: -47.9 dBFS (L), -48.9 dBFS (R)


Sharp DA - Sharp AD :  -53.9 dBFS (L), -55.2 dBFS (R)

Are really GOOD ! Well Done RME !
The ADI 2 Pro is also the best of RME's interfaces.

/Göran Nilsson

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

When looking at post #28 I doubt the relevance for all of the test results.

BR
Ramses
X10SRi-F, E5-1650v4, Win10Pro20H2, Cub11Pro, UFX+, XTC, 12Mic, ADI-2 Pro FS R BE, RayDAT

32

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

Yes, we are wasting our time - again. Instead of trying to understand what I wrote in post 28, or even to do the suggested test, the content of my post is fully ignored. Of course one might say, as it would cause the Diffmaker believers world to collaps. Still disappointing.

Regards
Matthias Carstens
RME

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

MC wrote:

Of course one might say, as it would cause the Diffmaker believers world to collaps. Still disappointing.

Yep - There were some snarky and dismissive posts on the GS thread relating to MC's post 28 and previous posts smile

MADIface-XT+ARC / 3x HDSP MADI / ADI648
2x SSL Alphalink MADI AX
2x Multiface / 2x Digiface /2x ADI8

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

I think we all have to (at least try to)  keep some concepts apart here.

1.)
The "GSloopBackTest" do not measure audio quality. No is does not. I totally agree with Mr MC.

BUT

2.)
The "GSloopBackTest" testresult is correlated with public perceived sound quality.

---------------------------------
Correlation does not imply causation:
https://en.wikipedia.org/wiki/Correlati … _causation       

/Göran Nilsson

35 (edited by ramses 2018-03-30 08:36:43)

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

kegn51 wrote:

I think we all have to (at least try to)  keep some concepts apart here.
1.)
The "GSloopBackTest" do not measure audio quality. No is does not. I totally agree with Mr MC.
BUT
2.)
The "GSloopBackTest" testresult is correlated with public perceived sound quality.
---------------------------------
Correlation does not imply causation:
https://en.wikipedia.org/wiki/Correlati … _causation       
/Göran Nilsson

to 2: no, this is simply personal perceived sound quality and nothing else.

People look at numbers, are prebiased and then the usual things happen (psychoacoustic effects).

And if you want to judge between i.e. 2 devices you need a valid A/B comparison and double blind tests as methodology.

BR
Ramses
X10SRi-F, E5-1650v4, Win10Pro20H2, Cub11Pro, UFX+, XTC, 12Mic, ADI-2 Pro FS R BE, RayDAT

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

If the Diffmaker results/figures touted as very good were SNR values or the like, they would be absolutely terrible...

I could post the following on GS, but I'd rather post it here, it will possibly find its way there.
I had an idea how to test the test, slightly different from MC's suggestions. There is no conversion involved, this uses digitally created files only. I hope I did not make any systemic or other mistake here. If so, I'll gladly accept any correction. Feel free to try this with other parameters. I don't know whether any such thing has been tested in all the years since this has been going on.

I created a 384 kHz Sequoia project out of which I exported 44.1 kHz files of identical length, but with different audio content (at the best possible SRC quality). One set of files with just a 1000 Hz tone, one with a combination of 100 and 1000 Hz tones. I adjusted levels and the position of the audio objects within the project, and exported the identical range to create files of the exact same length. I used the best possible values for time alignment and level adjustment in Diffmaker while comparing files.

First test: Comparing identical files, the result is, as should be expected:
Parameters: 0sec, 0,000dB (L),  0,000dB (R)..Corr Depth: 300,0 dB (L), 300,0 dB (R)

1000 Hz file tests, files with following changes compared to the original:

  • Level changed by 0.5: 0sec, 0,556dB (L),  0,556dB (R)..Corr Depth: 182,7 dB (L), 183,4 dB (R)

  • Level unchanged, position of audio object shifted by 1 sample (@384), to simulate a subsample delay @44 during conversion:
    (INV)parameters: 497,4usec, 0,000dB (L),  0,000dB (R)..Corr Depth: 84,3 dB (L), 84,3 dB (R) (not sure what INV is for, could not find anything).

  • Level unchanged, object shifted by 10 samples:
    Parameters: 974usec, 0,000dB (L),  0,000dB (R)..Corr Depth: 92,5 dB (L), 92,5 dB (R)

Identical results for files that were shifted and level-changed.

By Diffmaker standards applied to converters, these would be great results, but shouldn't  level differences and esp. time offset be compensated even better?


Second test, now it gets more interesting and seems to confirm what MC suggested (phase shift):

Combination of 100 and 1000 Hz tones, files with following changes compared to the original:

  • Identical files: 300

  • Level changed by 0.5 dB: Parameters: 0sec, 0,501dB (L),  0,501dB (R)..Corr Depth: 181,9 dB (L), 178,4 dB (R)

  • Level unchanged, 100 Hz object shifted by 1 sample @384
    (relative to the position of the 1000 Hz object):
    Parameters: -229,8nsec, 0,000dB (L),  0,000dB (R)..Corr Depth: 58,2 dB (L), 58,2 dB (R)

  • Level unchanged, 100 Hz object shifted by 3 samples @384:
    Parameters: -9,421usec, 0,000dB (L),  0,000dB (R)..Corr Depth: 41,3 dB (L), 41,3 dB (R)

  • Level unchanged, 100 Hz object shifted by 10 samples @384:
    Parameters: -2,298usec, 0,001dB (L),  0,001dB (R)..Corr Depth: 38,2 dB (L), 38,2 dB (R)

Identical results for files that had shift and level-change.

This is not complex musical material with a 20-20k range going through DA and AD conversion, these are digitally created files of a rather simple nature. It should be clear that there can be no audible difference between these files with such miniscule changes. Yet, the difference shown in Diffmaker results is quite significant and would suggest differences in "audio quality" that don't really exist.

Again, I hope there is no error in this test... The simulated "phase shift" values I used here are random, I don't know whether they would be in any way similar to real world values of DA/AD conversion. The idea was just to try to demonstrate how inaudible differences could cause results in Diffmaker that create a different impression.


Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

37

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

Yes, the second test should be correct to demonstrate that Diffmaker basically measures/weights the phase shift within a track, more than anything else, detects it at lower end (caused by the unavoidable high pass in front of any ADC) and at the higher end, caused by the various filters.

The filters combined with the analog output stage of the DAC cause a smooth phase shift in the treble region of less than 30° (worst case SD Sharp, measured with APx555). You will not find any proof that this is audible. Not at all.

Regards
Matthias Carstens
RME

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

I have now sent my "ADI 2 pro AE" back.

I compared it to my Steinberg UR824 and there was
not much (if any at all) of an improvement.

(I tried to be as objective when listening as possible.
Same loudness, treated room and good speakers. This can
be rather boring but is of course necessary.)

I will look for something more "HIGH END".

(I have really listened to it (both AD & DAC) and try to
like it but it was not up to my expectations. I am so sorry.
But I have learned much from doing so and that is the most
important thing for me.)

/Göran Nilsson

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

kegn51 wrote:

I have now sent my "ADI 2 pro AE" back.

I compared it to my Steinberg UR824 and there was
not much (if any at all) of an improvement.

(I tried to be as objective when listening as possible.
Same loudness, treated room and good speakers. This can
be rather boring but is of course necessary.)

I will look for something more "HIGH END".

(I have really listened to it (both AD & DAC) and try to
like it but it was not up to my expectations. I am so sorry.
But I have learned much from doing so and that is the most
important thing for me.)

/Göran Nilsson

I agree with you that you would not hear much if any difference. Under normal conditions you should not. All modern converters are great except when really badly designed. If one high end converter sounds really better/different then others they changed the sound from neutral, to a nice colour, they are not better. For example you can not hear the difference between -90 -100 or -110 db noise except when you play a signal at -90db or so, which at normal listening levels you can not hear at all. Same with distortion. Distortion is so low you can only hear it if you play a sine wave at those same low levels and cranck up the volume by 90db. And thing is you might even like the sound of higher distortion (I mean really higher like a defect), cause psychoacousticly we associate distortion with level and presence.

Vincent, Amsterdam
https://soundcloud.com/thesecretworld
Babyface pro fs, HDSP9652+ADI-8AE, HDSP9632

40 (edited by ramses 2018-04-06 18:00:23)

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

You are more likely limited by the capabilities of your speakers. I have heard the ADI-2 Pro and DAC in front of an ~€30k HiFi from my friend. Accuphase E600 with builtin Accuphase DAC-40 card and B&W 803D3. First it was hard to identify a difference, but after longer comparisons I tend to say that the ADI-2 Pro/DAC delivered a better more authentic presentation of the room where i.e. the vocalist was slightly better separated from the rest of the instruments in the background. For comparisons like this you also need to choose your sound material wisely, that the mix has good quality and you know this material well.

And even for my own use cases, i.e. in front of Geithain RL906D and with an Audeze LCD-3 phones it sounds better than before, although the upgrade from an RME UFX to UFX+ was nice already.

So the product is without any doubt on par with DACs being used in the high-end area and in regards to the additional features that RME bundles with it even better than many other products.

So if you say now that a low price product sounds the same as the ADI-2 Pro then its clear to me that either your speakers or your ears have deficits, so that its at the end not possible for you to recognize a difference between the low cost product and the ADI-2 Pro.

IHMO it doesn't seem to make any sense for you to spend even more money for another DAC with "questionable" more quality, but definitively less features.

Sorry, but from what I read from you I think your biggest problem is a certain lack of know how, experience and by this you come to wrong conclusions.

But maybe a new DAC will sound better to you because of psychoacoustic effects, if you pay more your brain will have the pre bias that it will sound better and then it will sound better for your ears. Brain can fool you very easy.

Good luck.

BR
Ramses
X10SRi-F, E5-1650v4, Win10Pro20H2, Cub11Pro, UFX+, XTC, 12Mic, ADI-2 Pro FS R BE, RayDAT

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

Could also be that a "coloured" DAC will give a more "high end" feeling.

42 (edited by Jantex 2018-04-10 10:25:47)

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

kegn51 wrote:

I have now sent my "ADI 2 pro AE" back.

I compared it to my Steinberg UR824 and there was
not much (if any at all) of an improvement.

(I tried to be as objective when listening as possible.
Same loudness, treated room and good speakers. This can
be rather boring but is of course necessary.)

I will look for something more "HIGH END".

(I have really listened to it (both AD & DAC) and try to
like it but it was not up to my expectations. I am so sorry.
But I have learned much from doing so and that is the most
important thing for me.)

/Göran Nilsson

Obviously your monitoring is pretty bad otherwise you would have noticed the difference immediately. ADI-2 Pro is sounding much cleaner with deeper low end and less distortion than anything I heard. It avoids the jitter which is pretty aparent at slightly louder levels, as you don't get the harsh spikes that so many converters (even high end) produce. Sound is smoother, but transients remain intact. Actually unbelievable clocking and conversion + all other features for the price. It makes competing product appear what they are - overpriced.

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

Agree. What I missed to wrote clearly was, he needs better speakers.

BR
Ramses
X10SRi-F, E5-1650v4, Win10Pro20H2, Cub11Pro, UFX+, XTC, 12Mic, ADI-2 Pro FS R BE, RayDAT

Re: "ADI 2 PRO" on the Diffmaker Gearslutz loop back test !

I also hear the clean detailed sound of the "adi-2 pro".
I am just to well informed to believe my ears without a proper blind test.

https://www.youtube.com/watch?v=kzo45hWXRWU

/Göran