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

Geert

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Watts doesn't claim to hear -300dB or -350dB though. He claims that he could hear differences between 2 different filters where the measurable differences for distortion were in that area.
That was also my understanding because if you gave it a long stretch that could somehow make sense. But there's more going on.

At 11:08 Watts states you can hear noise floor modulation below the level of measurability.
At 11:29 he applies that theory to mains cables, so it's not only about filters in DAC's.
At 11:44 he repeats immeasurable small levels of modulated noise can be detected by the brain, which affects sound timbre.
From 13:00 on he explaines how distortion between -130 dB and -150 dB is easily audible. OK, not -300 dB but does -150 dB make more sense?
At 20:46 he states no matter how small an error in a small signal is, it's audible. (Error refers to small signal linearity I think, as he explained before). From here on he applies this small signal theory to the noise floor of noise shapers, and that's where the -350 dB refers to. Not filtering but noise shaping. This time there's an effect on perceived depth
This is summarized at the slide at 23:10, which also states this theory explains why interconnects sound different.
At 28:20 he explains how noise floor modulation is responsible for the sound difference between different DAC concepts, like R2R DAC's.

A lot to unpack here. Nevertheless he repeatedly suggest immeasurable small non linearities in audio signals are audible, being it in mains cords, interconnects or DAC's. It's not realy clear if he attributes all of this to noise floor modulation.

Next to that, at 19:28 he explains how audio systems have a huge problem with depth, giving two examples (organ in a cathedral and barking dogs miles away). This is one of the problems he tackles with his -350 dB noise shaping.

According to me, the organ in a cathedral sound you can only try to simulate using multi channel recording and playback. Or do we have an Chord DAC owner who can confirm the depth of these DAC's is jaw dropping?

And a stupid question, if Chord DAC's can fix this digital audio reconstruction error that has a fatal effect on depth than this means we should also get this incredible depth perception from analoge audio, like tape or vinyl (where no noise shaping is involved). Can we indeed confirm the depth perception of digital audio is worse than with analog?
 
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Frank Dernie

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this incredible depth perception from analoge audio, like tape or vinyl (where no noise shaping is involved). Can we indeed confirm the depth perception of digital audio is worse than with analog?
This is a bit OTT but over 20 years ago when trying to evaluate the audibility of the various shortcomings of LP to try to understand why it doesn't sound as terribly inferior as the measurements suggest we did a listening test where the various shortcomings were compared one by one. The two things that stood out were that crosstalk better than 30dB was pointless and that adding noise gave the impression of more image depth.

I am content that more apparent image depth is a serendipitous effect of one of the shortcomings of LP rather than a superiority. We didn't try adding the sort of noise profile added by magnetic tape, but I wouldn't be surprised if a similar artefact is present.
 

tuga

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This is a bit OTT but over 20 years ago when trying to evaluate the audibility of the various shortcomings of LP to try to understand why it doesn't sound as terribly inferior as the measurements suggest we did a listening test where the various shortcomings were compared one by one. The two things that stood out were that crosstalk better than 30dB was pointless and that adding noise gave the impression of more image depth.

I am content that more apparent image depth is a serendipitous effect of one of the shortcomings of LP rather than a superiority. We didn't try adding the sort of noise profile added by magnetic tape, but I wouldn't be surprised if a similar artefact is present.

I wonder if (less) crosstalk isn't more important for the reproduction of music that has very complex sound (e.g. orchestral).

Do you remember which material was used in your tests?
 

DSJR

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I remember doing some vinyl vs. master tape comparisons over the decades (one later comparison done at Linn was the actual master tape and playback machine which cut the 12" single we compared it to, an acetate being cut on their Sculley lathe and then said acetate being played on their then top LP12 player, with the godawful in comparison LP version of the track played after for good measure - the vinyl was so bad it put me off vinyl seemingly for life! Wasn't until I heard a competing very small scale turntable range with Decca cartridge (separation on Deccas a whopping 20dB ;) ) that I heard something closer to master tape 'sound.'

This entire 'depth' thing isn't always heard that way on master grade recordings. I remember analogue masters often sounding 'dry' to me, where the vinyls made from them often had a kind of added 'halo' which certainly sounded 'nice,' but not what was there in the original. Old LP12 decks added a 'bloom' too, magnifying this effect and making some multi-track recording rock music disasters sound most inviting at the time on our then UK-scrappy sounding stereos.
 

Raindog123

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I always wondered where "people" go when vaporized by a phaser in Star Trek.

The answer is here: :)

8EBF6191-712C-449D-BCDE-9DB6D08CF58C.jpeg
 

Frank Dernie

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I wonder if (less) crosstalk isn't more important for the reproduction of music that has very complex sound (e.g. orchestral).

Do you remember which material was used in your tests?
Orchestral music was amongst the trials.
 

audio2design

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This is a bit OTT but over 20 years ago when trying to evaluate the audibility of the various shortcomings of LP to try to understand why it doesn't sound as terribly inferior as the measurements suggest we did a listening test where the various shortcomings were compared one by one. The two things that stood out were that crosstalk better than 30dB was pointless and that adding noise gave the impression of more image depth.

I am content that more apparent image depth is a serendipitous effect of one of the shortcomings of LP rather than a superiority. We didn't try adding the sort of noise profile added by magnetic tape, but I wouldn't be surprised if a similar artefact is present.

Noise can help extract low level detail.
 

SIY

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Some people are really interested what others are stating and others are not. The streamer was of a brand that promoted CD ripping engines and storage of WAV files. To make PCM better sounding then FLAC was a commercial interest maybe ? In case you're really interested, there is plenty of info on this on the internet.

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

sq225917

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Isn't it just RWs way of saying that he believes there is something audible going on that the numbers don't appear to indicate? Of course it's total bollocks hrs just setting himself up as a golden ear, now that he's reached the technological/mathematical limit of what's possible and needs a different story to sell...

For the record I admire the depth of his effort, irrespective.
 

DSJR

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Isn't it just RWs way of saying that he believes there is something audible going on that the numbers don't appear to indicate? Of course it's total bollocks hrs just setting himself up as a golden ear, now that he's reached the technological/mathematical limit of what's possible and needs a different story to sell...

For the record I admire the depth of his effort, irrespective.

Obviously I can't discuss his reasoning, but he IS playing to a particular audience hungry for subjective reasoning, who are usually thrilled just to meet the man and hear him speak, as well as being shown 'aspirational' products to perhaps lust after. I mean, none of these dems will ever include a £/$120 Topping or Schiit in a level matched comparison to show how small if not inaudible the differences actually are.

As regards Chord Electronics, it'd be interesting to see how they measure in comparison with other brands these days...
 

mansr

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Nah, you don't understand, I'm just spreading a bit of interweb trivia, not attacking anybody.
What, that there are people so miserable that they have nothing better to do than write lengthy posts poking holes in XKCD comics? Jeez, thanks for telling us.
 

jensgk

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Not quite related, but a little reminder that XKCD is a bit of a bad joke, outside Reddit.
Have not heard that, do you have any other sources for that claim? (there must be lots, since you call it "interweb trivia")?
Even though Randall Munroe, has a background in physics, of course he makes mistakes.
Also, there is nothing wrong with Reddit per se, just read the right forums..

ADDED: I do not understand why the text you copied as an image was not submitted here: https://www.explainxkcd.com/wiki/index.php/969:_Delta-P
 
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peterzuid

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Of course it’s of commercial interest! you have to be different in the market. Chord does the same thing. Being different works. And the best thing is: you can just claim to be different.. you don’t have to prove anything.



Let’s have it then.. we’re is it? Let’s dissect the nonsenses o_O

I think there is enough of it in the Naim forum including their own advice to use WAV;
BTW also my neighbor (and his wife) shared exactly the same experience with his Naim streamer,
Mind you; this all was more then 8 years ago.

I like the approach of Chord as mentioned and illustrated earlier though and expecting j-j to talk me out of it.

And let's skip the nonsense.
 

Raindog123

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I do not understand why the text you copied as an image was not submitted here

…not to mention that the “analysis“ by the author of this image-text — based on this supposed potential to kinetic energy conversion — is total bogus. As it has little to do with the XKCD‘s actual estimation approach that is simply based on the flow caused by the [gravitational] water pressure at the bottom of the ocean. As such, all the big words used by the dude — “laminar flow”, “friction”, “open system” — show nothing but his own rather limited understanding.
 
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