• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Resolving Measurement Issues with SONCOZ SGD1 DAC

EJ3

Major Contributor
Forum Donor
Joined
Dec 10, 2019
Messages
2,153
Likes
1,662
Location
James Island, SC
Differences can come from: Models that are cherry picked vs mass production, tolerances of parts, different test attributes used (Marv), different settings used, different levels used (Marv) or different ways to report.

Amir tries, Marv tries and GoldenOne tries and happen to use the same AP555X[/QUOTE]

In the high performance custom built automobile word of dynamometer testing we know that the testing is highly unlikely to give the same readings on a different dyno, even if it is the same model from the same manufacturer.
This case different AP555X testers gave vastly enough difference that a manufacture change was discovered (announced or not). That is something that happens & why it is good to have different people test things. It allows us to keep the manufacturers in the loop with their failures of action regarding updates. To improve the breed, so to speak. But it in no way reflects on the testers.
 

GeekyBastard

Active Member
Joined
Jan 27, 2019
Messages
249
Likes
565
Huh, Super Bullshit Arrogant Fiends... I never liked that forum before.
 

StuartC

Active Member
Forum Donor
Joined
Mar 8, 2021
Messages
154
Likes
398
Location
Rugby, United Kingdom
Nail on the head. The hobby problem, which is a reflection of bigger and deeper societal issues.

When one's beliefs—and therefore choices—are challenged by the truth, the truth in this case being science-based facts, and proven to be wrong, one can only respond in one of two ways, with anger or acceptance. Anger is so much easier because it reinforces one's perceived reality and maintains one's belief system. Acceptance is capitulation to the realization that your life has been wasted believing in something that is false.

These^^ One of the biggest problems with society today; People put more stock in measuring their own and others' worth by the products and articles they own, rather than their achievements or contributions to society. It's quite a sad state of affairs really.

Anyway, lets not derail the thread.
 

voodooless

Grand Contributor
Forum Donor
Joined
Jun 16, 2020
Messages
10,226
Likes
17,803
Location
Netherlands
In the high performance custom built automobile word of dynamometer testing we know that the testing is highly unlikely to give the same readings on a different dyno, even if it is the same model from the same manufacturer.
This case different AP555X testers gave vastly enough difference that a manufacture change was discovered (announced or not).

I’m not sure what you want to imply here? You cannot compare a car dyno with the AP system. They level of tweaking and precision tuning done with the AP is many many orders of magnitude more precise than that of those dynos. For all intents and purposes, all AP’s should measure the same given the same circumstances.

So yes, if the same device (as in presumed the same model) measure differently, it’s reason to calmly ask why that is in stead of starting to discredit people over half truths and misinformation.
 

StuartC

Active Member
Forum Donor
Joined
Mar 8, 2021
Messages
154
Likes
398
Location
Rugby, United Kingdom
I’m not sure what you want to imply here? You cannot compare a car dyno with the AP system. They level of tweaking and precision tuning done with the AP is many many orders of magnitude more precise than that of those dynos. For all intents and purposes, all AP’s should measure the same given the same circumstances.

So yes, if the same device (as in presumed the same model) measure differently, it’s reason to calmly ask why that is in stead of starting to discredit people over half truths and misinformation.

The only argument I can provide here is the (on this forum) proven difference that climatic conditions make to measured results (I think it was some Neumann speakers?) Granted, this will have a lesser effect on a purely electronic device (DAC for instance) over a speaker cone, but heat/cold soak is something that's considered in most every engineering exercise.

Nonetheless, the delta in performance will be significantly lower than an engine's power output at two different dynos with different humidity/temperature etc.
 

Tks

Major Contributor
Joined
Apr 1, 2019
Messages
3,221
Likes
5,494
He measured the same DAC but at different settings of the AP555X he just got and posted the results at SBAF.
Though the results are indeed poorer (as confirmed by Amir in this thread) and he was correct in posting it, the thread turned in the usual Amir bashing.
Someone on Reddit picked it up and used non averaged measurements from GoldenOne to make a case. Because of incorrect settings it looked worse. That's got nothing to do with GoldenOne and the critique about the DAC is valid.
Now, you can't expect a young economics graduate to fully grasp how to use an AP555x so he has some things to learn (don't we all ?).

I personally found his MQA bit wonderfully presented and think he is right. I can also understand Amir's admiration for MQA.
The real proof of the pudding would be lab conditions blind tests between MQA and WAV though.

GoldenOne mentioned he would do the blind test anyway and would donate funds he would get from sponsors. I am quite certain he would absolutely fail that particular blind test. no surprise... no public blind test. He probably tried it and failed is my assumption but in that case he learned something which was my goal.

No doubt he is being honest in what he does. So is Amir. At best, under equal circumstances testing the same gear the results from Amir, Marv and Goldenone should be the same.
Differences can come from: Models that are cherry picked vs mass production, tolerances of parts, different test attributes used (Marv), different settings used, different levels used (Marv) or different ways to report.

Amir tries, Marv tries and GoldenOne tries and happen to use the same AP555X

So quickly a few things. Why would it matter about GoldenOne not knowing how to "fully grasp how to use an AP555x" if everyone concludes his critique about the DAC measured is true. Like even if he posted non-averaged measurements - what precisely is the problem? I'd understand if he was trying to compare it to averaged measurements, that's a problem. But it seems the morons that went off with the non averaged results to try and fortify some conflict of interest claims are the ones causing the raucous? Or is GoldenOne with them on their claims?

As for his presentation on MQA, if that doesn't bury MQA with respect to mindshare of audio enthusiasts, nothing will. As for Amir's admiration of MQA, I can agree with you and say "I understand why he has some", I just don't see enough of an argumentative thrust to support willingly, the product they offer. I can admire Apple for instance, because they make the most well-finished mainstream products in the electronics market. But Apple as a company I'd have them jailed (along with others if I was a hypothetical king) generally speaking when their entire business is concerned overall. SO if Amir admires them for achieving what he attempted but for one reason or another was unable to at Microsoft; THAT I can understand. But if he admire's MQA for the product they're actually producing (not the type of product, but specifically their precise product) - that I can't understand, as it stands antithetical to much of how he thinks otherwise.

As for the blind test, I wish that went through. I think whoever was responsible for the ban should have thought about that event that GoldenOne was saying he was going to do. I don't understand why some restraint wasn't shown at least because he was willing to comply with a challenge. But I wasn't around this time, so whatever I guess. Seriously though, why was he banned since he complied with the challenge? Did he make death threats or something disastrous like that?

Is Marv = WolfX? Or is there a third person who got their hands on the AP that I missed?

But yeah, the last paragraph where you conclude about the different parties is what I also feel. It just would seem perplexing to me, to have public personalities playing favoritism games. I expect that kind of garbage from subjective reviewers. Not from people plopping down for test gear costing the better part of a luxury car. So I never assumed any of those sorts of folks are cooking the review measurement books. I have no problem with anyone's measurements, even if they use "wrong" parameters (it seems they're only "wrong" when one wants to do a comparison, it's not like the AP is wrongly spitting out data or something).

Though there is one thing I actually don't like about all AP reviews I've seen. Almost all of them, when you see the output level. When it's tested for 2V or 4V (but especially 4V output), it's heavily inconsistent. Always something like 3.9, or sometimes 4.3. I just don't get it, does the AP not have real-time power readings? Or is it that tough to rotate the volume knob on an amp or DAC and nail a 4.0 (give or take a few microvolts)? I know some devices can't reach 4V, so for those instances I understand. But those weird 4.3v measurements bother me for some reason. Especially when it's being done with 120dB SINAD sort of devices. It's not fair one gets tested at 4V while the other is at 4.3V, seems like that could make the difference between 120dB and 118-119dB SINAD which is HUGE for competitors chasing spec numbers at that level. Just to be conclude and be clear, I am not talking about devices where MAX output is tested for (like some devices that go to like 7V+ just to show what they can do, I'm strictly talking about the 4V spec that's commonly used).

Oh solderdude, btw since I have to contend with nebulous descriptors about the situation. What exactly were the measurements Golden posted that people are taking issue with when comparing to Amir's? And when he was told about "wrong parameters" what was his response?
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
44,368
Likes
234,386
Location
Seattle Area
Always something like 3.9, or sometimes 4.3. I just don't get it, does the AP not have real-time power readings?
Before I answer this, I want to caution you to not drag this thread into other topics such as MQA, our admin decisions, etc.

The input to a DAC is digital. And volume control is usually the same so it is not a variable voltage you can just dial in. The volume control on the DAC if it exists, is usually too coarse for fine tuning. One click may go from 4.2 volt to 3.9. On AP, I can change 0 dBFS to some other number. I tend to not want to do that because then we are feeding the DAC a fractional test signal which is no longer is bit exact. To the extent I can adjust it with 1 or 2 dB deduction, I do. At the same time, I don't lose sleep over 3.9 vs 4.1 volt.
 

solderdude

Grand Contributor
Joined
Jul 21, 2018
Messages
15,891
Likes
35,912
Location
The Neitherlands
I don't want to clutter the thread up more than I did.

My remark about goldenone was that he had things to learn operating the AP555. Nothing more.
Amir made the remark about averaging making the plot that was discussed look worse (not invalidate it).
That's all. Also remarked that certain threads/fora are to discredit Amir at any given opprortunity.

Marv = Marvey = Marvin = Purrin = the messiah = SBAF guru. Not Wolf-X

Better to discuss the 4V thing in an appropriate thread.
 

Tks

Major Contributor
Joined
Apr 1, 2019
Messages
3,221
Likes
5,494
Before I answer this, I want to caution you to not drag this thread into other topics such as MQA, our admin decisions, etc.

The input to a DAC is digital. And volume control is usually the same so it is not a variable voltage you can just dial in. The volume control on the DAC if it exists, is usually too coarse for fine tuning. One click may go from 4.2 volt to 3.9. On AP, I can change 0 dBFS to some other number. I tend to not want to do that because then we are feeding the DAC a fractional test signal which is no longer is bit exact. To the extent I can adjust it with 1 or 2 dB deduction, I do. At the same time, I don't lose sleep over 3.9 vs 4.1 volt.

Oh wow, DAC's are that coarse? Yuck.

Oh and as for tangential topics, I'll just PM solderdude to get any details I missed out on. You're right, no need to spam asking about history.
 

saich

Member
Joined
Jul 9, 2020
Messages
20
Likes
11
My remark about goldenone was that he had things to learn operating the AP555. Nothing more.
Amir made the remark about averaging making the plot that was discussed look worse (not invalidate it).
That's all. Also remarked that certain threads/fora are to discredit Amir at any given opprortunity.

That's a good point. Not averaging the plots does not invalidate it. I think Golden does the same to every other stuff he's tested. So I don't think he did so to make the Soncoz look bad. It's just that his results would not be comparable to Amir's, or at least not directly (visually). But any one familiar with how to read charts should understand they are essentially telling the same story with or without averaging.

I for one agrees on the need of standardizing AP test project file.
 

danadam

Addicted to Fun and Learning
Joined
Jan 20, 2017
Messages
956
Likes
1,496
Oh wow, DAC's are that coarse? Yuck.
I don't know, it is -0.64 dB from 4.2 to 3.9, if my calculations are correct. I'm not sure if a regular user needs finer control.
 
  • Like
Reactions: Tks

NoteMakoti

Member
Joined
Apr 8, 2021
Messages
53
Likes
143
I don't know why they're all so goofy about this. If a headphone measures badly and you like it, how does a negative review change that? They don't want a review, they want affirmation.
 

EJ3

Major Contributor
Forum Donor
Joined
Dec 10, 2019
Messages
2,153
Likes
1,662
Location
James Island, SC
I’m not sure what you want to imply here? You cannot compare a car dyno with the AP system. They level of tweaking and precision tuning done with the AP is many many orders of magnitude more precise than that of those dynos. For all intents and purposes, all AP’s should measure the same given the same circumstances.

So yes, if the same device (as in presumed the same model) measure differently, it’s reason to calmly ask why that is in stead of starting to discredit people over half truths and misinformation.
The point is that different operators will likely do something different (unless one was trained by the other [and/or conditions will be different]). Warm up, ambient temp (68F vs 82F), many factors, some that one test equipment operator may control & another may not. At this point, Amirm is one of only a very few operators (probably only) of the AP555 that I trust due to his extensive knowledge of the subject matter & ongoing learning & continuous refining of the testing procedures and conditions. That is the same truth with dyno operators (not all dynos are engine dyno's, there are transmission dyno's, etc).
As to a dyno, the level of sophistication varies: A modern, sophisticated engine and transmission dyno can take, as its input, a typical duty cycle for the complete 24 hour race. This means that the engine will be throttled, on the brake, as if it were completing a lap of the circuit, the transmission will be shifted as per the requirements of the lap, and the complete driveline assembly, including driveshafts and wheel hubs (& fuel use efficiency) will undergo this simulation over a period of perhaps 28-30 hours. This is necessary to ensure that an engine-driveline aggregate that has achieved 24 hour durability, but was about to fail after 24 hrs and 5 minutes is not signed off! There will of course be a statistical factor of safety, or in this case longevity that needs to be accounted for, in much the same way that when stressing for fatigue we look at number of cycles to failure, and then add a factor. They'll also have been tuned to represent idiosyncrasies of individual drivers' styles: "driving styles can vary," notes an F1 power unit engineer. "That means we need to prepare higher numbers of options in terms of energy management. More options means we need more time for preparation."
 

Victoria

Member
Joined
Jul 26, 2019
Messages
86
Likes
269
I admire that you countered the claims and accusations in that Reddit thread . . . Although sometimes amusing and entertaining, Reddit has to be one of the least credible sources out there (IMO). I like the poster who said something about "alternate facts" -- if there is data that has been truly researched, tested, and scientifically documented, there are no such thing as alternative "facts" -- we live in some crazy times. Bravo, Amir, for putting in the extra work, debunking the naysayers, and maintaining the integrity of ASR !!!

Ah Reddit; Reddit never changes. I used to attempt to engage in discussions on Reddit a long time ago, and I say “used to” only because I have since nuked my account for my own sanity since Reddit is by-design the single largest “hug box” and “echo chamber” on the entire internet to the point of it being borderline dangerous.

Let’s face the facts: Reddit does NOT promote open and fair discourse, as a matter of fact it actively encourages the contrary. Even just setting aside how isolated many communities are: if you’re not fighting against overzealous and heavy-handed moderation policies by juvenile moderators who make IRC operators from the 90’s look like saints, then you’re fighting against the hoard of down-voters who will send your comments into the deepest depths of the ocean merely for daring to voice an opinion — or even fact — that goes against the beliefs of the herd. Almost everyone on Reddit exists just to stroke each other’s ego, just to seek validation and to karma-whore, just to parrot in perpetuity what has been safely said dozens or even hundreds of times prior irrespective of reality.

All that matters on Reddit is the popular narrative, say anything else and good luck finding your comment anywhere in the thread. Top posts — and thus by extension the most visible posts — are just whatever the popular opinion is, and Reddit by default hides and collapses comments with negative downvotes.

I’ve witnessed on numerous occasions posts which are blatantly false overshadow posts which attempt to factually address the subject at hand, because all that matters is how many points a post has, how popular the opinion is; and this is why Reddit is dangerous. Reddit forces people into their own little isolated communities — over a hundred thousand active subreddits from what a quick search is bringing up — where nothing but the popular opinion thrives; and when open discourse is stifled to such extremes all that’s accomplished is the dilution of facts, the slow but assured detachment from reality. Thank you Amir for mustering the strength to put up with this, because I’m quite sure I’m far from the only one who has long lost the energy to fight against the Reddit herd; I can only allow so many of my brain cells to commit suicide.
 
H

Hifihedgehog

Guest
we must remain vigilant in the face of alternate facts, the dearth of civilization.
One good way to stay vigilant is to remember that there is no democracy of facts or equality of information. Many facts are extraneous or aesthetic in intrinsic value bearing no relevance or priority at the core of reality and the topic of discussion. Many so-called alternative facts are the ever-popular "my" truth, which is really a modern subversion of the term "a poorly informed opinion" fabricated by weak minds who realize they stand on flimsy reasoning. Worse yet, many alternative facts are outright lies based on rash assumptions or clever deception which are weaponized to inflate one's ego and expand their influence.
 
Last edited by a moderator:

pseudoid

Master Contributor
Forum Donor
Joined
Mar 23, 2021
Messages
5,116
Likes
3,416
Location
33.58 -117.88
Everyone chill!!
If you were still in diapers when the brand Brüel & Kjær was the gold-standard; you may want to stop and smell the (repurposed) coffee here <
>. After 8+ pages of replies, we all deserve a historical and a relevant perspective break (turn down volume).
Warning: I may be from that old "they don't make them like they used to" skool.


NOISE! DITHER! DFT! FFT! Even the APx555 analyzer ALL BE CURSED & DAMNED!
One can NEVER 'resolve measurement issues' if the target is an update-driven software (=moving) goalpost!


I feel for @amirm for having to defend his reputation elsewhere, and the rest of us also getting suck'd into the vacuum of social media.
 
  • Like
Reactions: Tks
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
44,368
Likes
234,386
Location
Seattle Area
All that matters on Reddit is the popular narrative, say anything else and good luck finding your comment anywhere in the thread. Top posts — and thus by extension the most visible posts — are just whatever the popular opinion is, and Reddit by default hides and collapses comments with negative downvotes.
This has another nasty side effect. If you don't respond in the thread and say, wait a couple of days, it disappears from top threads and no one cares! It is a total waste of time to post anything then.

It is a super weird social engineering and has the consequences as you mention. The loudest group think wins and that is it.
 
Top Bottom