Distortion down to -300 dB, what exactly does that mean physically?

[richard12511]

It is not a matter of opinion. It is a matter of stablished audio research/science that we used controlled, blind tests to establish audibility. I have also taken countless blind tests on my own and know that it doesn't have to be stressful at all. What is the stress if no one is looking over your shoulder at home?

Also, if a little stress is enough to completely hide the improvements your $8,000 DAC makes, then those improvements must be pretty small. If the sound quality improvements are really that tiny, I would say the device is probably not worth the asking price.

 

[richard12511]

There's also plenty of info on alien abductions with anal probing, and not coincidentally with the same level of evidence.

I'm unlucky enough to experience sleep paralysis once a year or so. As a regular sleep paralysis victim, I'm convinced that most of the alien abduction reports(at least the ones where the people honestly believe it) are a result of sleep paralysis. I've never been abducted, but I've had aliens at the foot of my bed a few times trying to run tests, been assaulted by all sorts of demons, and Samara from "The Ring" is a common visitor. These days I can mostly shut it off within a few seconds, but that's because I know what it is and my conscious mind can convince my brain to turn on the muscles(and turn off the dreams). First time it happened, I had no idea what it was, and I can certainly understand why victims might think it was real.

 

[Raindog123]

Go back a few pages and read his posts. He was not engaging in honest let’s share knowledge and learn enthusiasm. He was trolling, pure and simple. As for the behavior of Senior Members, they have earned the right to become arrogant when they know they are being trolled in their own house. I hope you stay long enough to discover that yourself. Because of what ASR does, calling out the over abundance of BS snake oil products that exist, we draw lots of Trolls who come here just to cause disruption and mayhem. Lots and lots of people who have paid big bucks for crap don’t like being told they bought crap. For some it gets personal. My job is to smoke these bad actors out. That is precisely what I did. Some might even accuse me of giving them too many benefits of the doubt. Or to stick with the analogy, too much rope.

BZ!

 

[Geert]

Maybe I’m missing something, and opinions aside, I personally thought Peterzuid conducted himself in quite a reasonable manner? While some of the ‘Audio Luminary’ came across fairly aggressive and with a touch of arrogance.

That's exactly how a smart troll operates; being not to offensive but steering the discussion in a way others become emotional and look bad. This has been going on for almost a week: making outrageous claims, playing the person and not the ball, persisting, cherry picking, going off-topic...

 

[Frank Dernie]

Also, if a little stress is enough to completely hide the improvements your $8,000 DAC makes, then those improvements must be pretty small. If the sound quality improvements are really that tiny, I would say the device is probably not worth the asking price.

This was the conclusion I came to when I did a DAC evaluation about 10 years ago. If the differences i thought I heard were so tiny it was a strain to detect them and I couldn't consistently do so the DACs were, for me, not worth considering to actually be different from the perspective of using them for listening to music for enjoyment.

 

[sq225917]

That's how I do all tests, if I can't hear a difference within a few seconds, or can't hear it once an attempt has been made to highlight it for me then its not worth me worrying about, my hearing ain't good enough or the effect is too low in level/ doesn't actually exist.

 

[tuga]

This is Hi-Fi News' Paul Miller (Miller Audio Research):

Mola-Mola teases in its specification for the Tambaqui by stating 'THD not measurable – estimated –140dB' although, in practice, this rather depends on level and frequency.
I was still able to discern residual 2nd-4th harmonics at higher frequencies, lower than recorded for the Makua (0.00014-0.003% re. 0dBFs, 20Hz-20kHz) but still fractionally higher than that achieved by another custom DAC – the Chord DAVE [HFN Apr '16] at 0.00002-0.00008%.
Either way, the Tambaqui's 0.00005-0.0005% puts this exquisite DAC in the same class as those very few requiring a 'recalibration' of our distortion Y-axis from –120dB to –140dB [see Graph 1].
Subjectively, it's all rather academic, of course!

https://www.hifinews.com/content/mola-mola-tambaqui-network-attached-dacstreamer-lab-report

 

[audio2design]

Go back a few pages and read his posts. He was not engaging in honest let’s share knowledge and learn enthusiasm. He was trolling, pure and simple.

While I didn't find senior members to be overly arrogant though presented lots of opportunity, I don't think PEz was trolling either. This is how brainwashed people let themselves become. He would be more akin to a zealot, the guy with the Jesus sign at the atheist rally as an analogy. These people are "turnable", but it's questionable whether the effort warrants. Given the thread topic though it's a good reminder for us science types what's out there.

 

[AdamG]

When you become a Complaint Magnet and a stand out Science Denier your days are numbered here. He was both and came on my Radar far too often for a New Member. New Members are scrutinized to a higher degree by Senior Members. I appreciate the feedback and want to hear other’s opinions. Just keep in mind that you may not be in possession of all of the facts involved in the decision making process. Banning Members is our last resort and reflects a failure on my part to nurture and grow our community. I take it personally.

 

[Spkrdctr]

Go back a few pages and read his posts. He was not engaging in honest let’s share knowledge and learn enthusiasm. He was trolling, pure and simple. As for the behavior of Senior Members, they have earned the right to become arrogant when they know they are being trolled in their own house. I hope you stay long enough to discover that yourself. Because of what ASR does, calling out the over abundance of BS snake oil products that exist, we draw lots of Trolls who come here just to cause disruption and mayhem. Lots and lots of people who have paid big bucks for crap don’t like being told they bought crap. For some it gets personal. My job is to smoke these bad actors out. That is precisely what I did. Some might even accuse me of giving them too many benefits of the doubt. Or to stick with the analogy, too much rope.

That is the reason so many people are on the site. We have all kinds of people who have real life experience that shows how snake oil is running amok in the audio world. Arguing against people who have a lifetime in this is foolish. Especially when you are not aware of the science and the testing that has been done. For example, many fairly new posters will say "How come no one double blind tests these ideas?" Then I have to post that we/they have and it's been done for 40 years. But, the industry does not want anyone to know the results and a lot of it is proprietary. But we do know the facts as they are now. Until there is a new or big break through that changes something, we know A LOT about what humans can actually hear when listening to their audio system. So, the tolerance for Johnny come lately people to argue against the established science and testing, like they came up with a new thought is hard to take. But, we do try to educate best as can be done on a website. I think the moderators have been VERY fair with people. They let them air their ignorance and wait to see how they respond to people who know the facts. Then they moderate if needed.

 

[DonH56]

When you become a Complaint Magnet and a stand out Science Denier your days are numbered here. He was both and came on my Radar far too often for a New Member. New Members are scrutinized to a higher degree by Senior Members. I appreciate the feedback and want to hear other’s opinions. Just keep in mind that you may not be in possession of all of the facts involved in the decision making process. Banning Members is our last resort and reflects a failure on my part to nurture and grow our community. I take it personally.

Don't. You do a fine job, if anything letting out more rope than others (like me) might. To corrupt an old analogy to the way Grandmother would sometimes phrase it: you can lead a horse to water, but if all he does is turn around and bray at you like a jackass, then shoot him or walk away. When people have their minds made up, and argue against all counterpoints without trying to understand any of them, it is pretty much a lost cause. The main reason to continue to post the counterarguments is the hope that somebody else reading will actually pay attention and learn enough to make an informed decision. Sometimes it is a forlorn hope.

 

[peufeu]

Most of what Mr Chord said in the video made a lot of sense...

 

[SIY]

Most of what Mr Chord said in the video made a lot of sense...

Uh huh.

 

[peufeu]

Uh huh.

Well yeah, but what I find surprising is he seems competent but he didn't mention the obvious: if there is an audible difference that is correlated with a measurement that's a whooping number of dBs down, so low it would be ridiculous to pretend to be able to hear a signal that many dBs down, then it means either the audible difference is an illusion, or the wrong measurement is being used... Maybe it is measuring something vaguely related to the actual cause and showing a tiny blip, but the actual stuff is much larger, at audible levels, and the measurement in question is not designed to catch it, so it does not catch it.

For example FFT does a lot of averaging so it is very good at catching harmonics, but if you have intermittent nonperiodic random spikes (think of vinyl cracks for example) or many other kinds of error and distortions that are not harmonics of the signal, not periodic, and/or have a somewhat random character, then it will just show up as a rise in the noise floor which is difficult to interpret. The energy of this type of error signal is spread over many FFT bins so it looks tiny, and it's not possible to know its real amplitude by looking at the FFT. So FFT is unsuitable for catching this kind of defect. People call it "noise floor modulation" because that's what it looks like, but who knows what's in that noise.

 

[SIY]

Well yeah, but what I find surprising is he seems competent but he didn't mention the obvious: if there is an audible difference that is correlated with a measurement that's a whooping number of dBs down, so low it would be ridiculous to pretend to be able to hear a signal that many dBs down...

Full stop right there. Audible difference asserted, not demonstrated.

 

[scott wurcer]

example FFT does a lot of averaging so it is very good at catching harmonics, but if you have intermittent nonperiodic random spikes (think of vinyl cracks for example) or many other kinds of error and distortions that are not harmonics of the signal, not periodic, and/or have a somewhat random character, then it will just show up as a rise in the noise floor which is difficult to interpret.

Little if any of this applies 150dB below an ideal -144dB DAC.

 

[peufeu]

Little if any of this applies 150dB below an ideal -144dB DAC.

What makes me take the claim with a bucket of salt is this: it all happens in digital domain, so the first thing to do would be to substract output from input and see what it looks like. But he doesn't talk about that at all.

 

[Geert]

What makes me take the claim with a bucket of salt is this: it all happens in digital domain.

Remenber Watt's also claims noise floor modulation in interlinks and main cords. So null a stock and a 'high end' interlink to see what's he after.

 

[Blumlein 88]

Remenber Watt's also claims noise floor modulation in interlinks and main cords. So null a stock and a 'high end' interlink to see what's he after.

When I do that I get nulls of -110 db which is mainly the noise floor of the ADC in use. I don't see any noise floor modulation when running the appropriate tests. So the modulation must be at least 20 db below the -110 db level. Is that something Mr. Watts can hear? No it isn't.

 

[peufeu]

Remenber Watt's also claims noise floor modulation in interlinks and main cords. So null a stock and a 'high end' interlink to see what's he after.

That claim is difficult to test, because it depends on the setting. The guy who claims a strong effect from interconnects in his system can always say that's because there's a lot of RF interference in his listening room, but it's not possible to know if that is true over the internet.

Basically, "this product cures a defect from an invisible form of voodoo" is a strong marketing tactic, but that does not mean it is false (unless the description includes the word "quantum" of course)...