Oh, you are so kind! Much appreciated.

Ah, thank you so much!

You are so kind. Thank you very much.

Hi-fi reviewers have been using measurements for more than 30 years, but unlike Amir, they have found that it tells us very little about how we experience the test object, so they typically use the ear and experience as the most important part of their review. There are plenty of sound differences that can neither be measured nor explained, you will discover this when developing high-end from scratch, the fact that we can't measure everything is why so many people are still searching for answers and why there is so much diversity in high-end. An AP analyser is just a simple tool and not the answer, and Sinad's ranking is just plain stupid.

You simply don’t get it do you ? HiFi reviewers who do use any significant amount of texts and measurements in their reviews (eg John Atkinson ) for the most part simply choose to ignore them and prefer to go with their ears/judgement/ BS , call it what you want . They have merely groomed you and seduced you and you have fallen for it (as I used to and as many here on ASR used to) . The very best audio components are the ones that you don’t hear ie the ones which are transparent to the signal (and the listener). All you hear in fact are the source recordings and the speakers and the latter aren’t possible to make inaudible BUT they can be made better than the vast majority of “HiFi” speakers happen to be made.

@@davidcarr2216 I have my own opinions and experiences, you are the one who has been groomed by ASR Amir, wrote a previous post where I explain. kzfaq.info/get/bejne/mNakacaovqzIqKc.html&lc=UgzgbqFuIA2FyOjBaK94AaABAg

Yes thank you Amir! You can’t know exactly how any system is going to sound and whether you are going to like it until you buy it and put it in the room you want it in. Given that, I think it makes sense as consumers to buy out of the products Amir and some other competent individuals have measured. Yes, maybe we can’t measure all attributes of sound yet (maybe we need some sort of quantum analyzer (or maybe that wont even be enough)), but there are tons of great performing products that Amir has reviewed that still potentially have those small, potentially immeasurable discrepancies between them which we can pick from. No need to spend mucho dinero to test even like 5 of them until you are content with the sound. You get more diversity that way when they are priced lower since you can switch them out and sell when you get bored. If you’re a hobbyist, then you enjoy this stuff and don’t mind the cost, but if you’re looking to make let’s say 3 test purchases max for each component in your system, it makes way more sense to shop the products Amir has reviewed.

You are very kind. Thank you.

@@AudioScienceReview The work you are doing is so important. People who sell snake oil products to uninformed or very low information people at highly inflated prices, are not only stealing from the poor people they sell to, but hindering real progress and thus stealing from everyone. You are a guiding light in the industry and totally deserve this recognition.

Other tests show that. But you can also infer that from SINAD in the dashboard. Look at the amplitude of distortion spikes. If they are at say, -120 dB and SINAD is 110, it tells you that noise is 10 dB higher. This is then confirmed with my dynamic range test. IMD test also shows this: where it is sloping down in the sweep is noise dominated. When the curve flattens or starts to tilt up, distortion has increased beyond noise levels.

First, thanks for kind words. What you say is what many of us also observe. The thing is, when we match levels and do the testing blind, those differences vanish. Please try it that way.

$1k vs $10k DAC...the only prices that matter relative to output quality are the PARTS prices. The Retail price is merely a function of profit. So...I have some magic cables that you can purchase if desired. Priced at $10k.and will give you 3D holographic, deep, clarity, etc. Ignore the goodwill stickers.

I don't think the equipment Amir tests which does not perform well is the result of manufacturing defects. I think almost all of them are just not good designs. The $80 Chinese DAC just starts out as a well implemented design. He mentions a "closed loop design process" in the video. Basically you start out with a set of customer requirements, like better than CD audio performance. Then you develop that into a technical requirement, like SINAD > 96 dB. Then you design and build your first prototype. While it is off being built you look at your requirements and you develop a test plan. Once you receive your prototype you execute your test plan to check your design against the requirements. If it is not good enough you re-design. Once the requirements are met final qualification testing is done and you start manufacturing the product. You are checking your design against the requirements and feeding that information back into the re-design process. This is the "closed loop". Typically in electronics manufacturing you are not conducting full testing of any product that comes off the assembly line to a standard remotely close to what is done in the qualification phase of development of the product where all specifications are tested. As a development engineer I would attempt to convince manufacturing to run a 1 kHz tone through a DAC and test for SINAD, but that would be about all I would expect them to agree to. A test like that would be relatively cheap and could be quickly automated. The multitone distortion test could also somewhat easily be run during manufacturing, but the results of the test are a bit more difficult to interpret than a SINAD test. For a stereo DAC this would probably not be a problem, but for a multichannel DAC it starts to add up. Time is money and most testing done on the manufacturing floor is rudimentary (Do the LEDs work? Are the power supplies all putting out the correct voltage? Has the firmware successfully been written?). I think it's also largely unnecessary to do such testing. First articles (the first unit(s) produced of a given design - only done one time for the very first manufacturing run of a product) are scrutinized to ensure they are able to meet the manufacturer's claims (hopefully), but with the nature of surface mount electronics manufacturing being so highly automated and repeatable and the cost of testing typically being so high, thorough testing is almost never done in manufacturing. For consumer products I would be surprised if each manufacturing run is sampled for full testing at all. To keep overhead costs low electronics manufacturers do not want to run one or two samples on their lines and then wait for results from the test lab. Those machines cost a fortune and any idle time is revenue lost. Each time a machine is setup for a different build all of the component reels need to be unloaded from the last run and all new reels loaded into the machine. Stencils that allow the solder paste to only cover the spots where component leads will land must be fitted. It's not cost effective to build only a couple boards. Usually there are large setup fees when a batch of boards are run specifically for this reason. The more boards you can run at a time the more spread out the setup costs are. There are customers who may require it and the cost of the products usually reflects that, However, my guess would be that in consumer audio price is unlikely to be an indication that any thorough manufacturing testing is taking place, even of the most basic parameters like SINAD. Amir gets to this when looking at the correlation of price and SINAD performance. But again, I doubt the problem is manufacturing - it is almost certainly the design.

@@Fix_It_Again_Tony "I don't think the equipment Amir tests which does not perform well is the result of manufacturing defects." I agree, it's poor design and build. "Once the requirements are met final qualification testing is done and you start manufacturing the product. You are checking your design against the requirements and feeding that information back into the re-design process. This is the "closed loop". Not a closed loop since components purchased for the assembly could be different than those used to build the prototype. Different build lots that can effect performance. Changes or lack of control in the build process can also effect performance. "Typically in electronics manufacturing you are not conducting full testing of any product that comes off the assembly line" This is not true! The product coming off the assembly line needs to be tested to verify it meets the specification defined in the prototype which was build at an earlier time using components from a different lot. "For consumer products I would be surprised if each manufacturing run is sampled for full testing at all." Sample testing using statical analysis can be used in place of 100% testing and still assure products are meeting design specifications with a high level of confidence. Statistical process control is a standard practice across all industries for testing and measurement, except for mission critical items which are tested 100%. " I doubt the problem is manufacturing - it is almost certainly the design." Generally this is true but without a consistent method of verifying processes used in the build cycle, there is no guarantee products will consistently meet the design specifications.

If you don't have sufficient control over your process to ensure the same manufacturer parts are being used in the prototype and manufacturing phases, then that is a problem and manufacturing testing is not the way to solve it. A first article test covers the case when you want to test the first manufacturing run. This test is used to ensure the manufactured products are the same as the prototypes. Sample testing can be used. When I say "full testing" I mean mean qualification testing when all specifications are tested. We specify an operating temperature range of -40 to 70 °C for our products. We surely do not test over temperature in manufacturing.

You have to remember that your audio gear is dumb. It doesn't know what a violin is. Or a sine wave. Or noise. Something goes in, something comes out. That transfer function is easily attained using measurements. It is all varying samples going into the DAC whether they have a pattern or not. The system also has no memory in that it doesn't know what came before or after. In other words, it is a very simple system and as such, measurements fully quantify it. Once there, we don't just stare at the numbers. We use psychoacoustics to analyze them. And that science is formed with listen tests. The combination tells us that you can buy a DAC now for $80 and get transparency to the source. Whatever is wrong belongs to the source, not the DAC. You can also waste money buying an $8,000 DAC that spits out noise and distortion far more than that $80 DAC. The attributes you talk about are properties of the source music. Let's remember that the talent and producer didn't have your DAC yet they approved said content. When people say DACs have this and that sound, they are putting opinion in there formed by uncontrolled listening. Once the identity of what they listening to is taken away, all of those attributes disappear. So surely they are not from the equipment, but one's imagination and imperfect listening.

@revelry1969 Thanks, whatever equipment we are talking about, dacs amps or beyond, I can tell you that recordings usually don't sound correct in playback with the instruments I know and have played for 30 years since I was a kid. What you wrote here is something I have suspected for a long time, just never seen it put together so neatly. Chasing gear that can do it has become a challenge.

Asking the wrong person. ASR are intelligent dummies. Here’s a wisdom drop for you… ​​⁠​⁠​⁠”man has such a predilection for systems and abstract deductions that he is ready to distort the truth intentionally, he is ready to ignore the evidence of his senses only to justify his logic.” Dostoevsky

@@AudioScienceReviewyet many people experience different to what you claim. Your arrogance is amazing. Even double blind listening tests have been done to refute many of the things you claim don’t exist. You’re living in a delusion 😂

@@chungang7037 thank you for your note. Amir has the right tools it seems but maybe measuring things that aren’t that important. Hope we can get closer to understanding this into the future.

No, that is correct. You do need 10 dB extra so that you don't add to that noise floor.

@@AudioScienceReview ah thanks for your reply. I’m trying to understand this and maybe I was thinking about it incorrectly. Is it then that the range on a good recording between the loudest notes and silence needs 18bits dynamic range so that when the music fades to silence, that silence stays above the noise?

Thank you for kind words. I use a Topping D90SE.

Add knowledge of how we hear and then it can. Conversely, bad measurements for sure don't indicate something is good and means it can have audible issues.

Well said. When I go to audio shows and they are playing LPs with pops and clicks, it is shocking to me. I literally jump. Then I look around and realize others didn't even realize there was a click/pop!

If the clicks and pops are optional, they may be more tolerable than when we had no choice in the matter.

The paper was not peer reviewed. We decided late in the game to submit one and deadline for that had passed. I plan to write more next year and will decide if that is something useful to do. Since my work is not pure research, there is less value in such reviews.

@@AudioScienceReview I see, okie thank you Amir! Appreciate the work you do.

Amazing! Thanks for all the hard work!

I ran into that as well when I was trying to find the paper to show in the video. I don't know what is going on. I did put the link in the description. Here it is again: www.aes.org/e-lib/browse.cfm?elib=22278

There is not just one but many. For me personally I actually use RME ADI-2 Pro for its capabilities and display even though technically it is not quite as good as other bare bones DACs.

Some of those were on loan so went back their owners. But much is stacked up here going almost to the ceiling! They are just off camera in the video. I probably have 200 here!

SMSL SU-1: www.audiosciencereview.com/forum/index.php?threads/smsl-su-1-stereo-dac-review.44029/

That was really nice of you. THANKS!!! @@AudioScienceReview

Yeh, filter 1 which is the default starts to cut off the highs from 10 kHz on! They have been doing that in all of their products until now.

Audio Science Review website

As noted, go to ASR and you see the graphs on everything tested. If you are looking for something specific, you can go to the index and search there: www.audiosciencereview.com/forum/index.php?pages/Reviews/

@@emilspec1227 Thx !

@@AudioScienceReview Thx!

Thanks. When I get a chance, I will plot that chart with log scale in the corresponding thread on ASR: www.audiosciencereview.com/forum/index.php?threads/aes-paper-presentation-on-dac-measurements-video.50277/

Depends on which $10 DAC you are talking about. Some like the Apple dongle is very good. Others like no-name ones online are pretty bad.