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Serious Question: How can DAC's have a SOUND SIGNATURE if they measure as transparent? Are that many confused?

BDWoody

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Why do audiophiles hate the Fourier transform so much? Were they promised there would be no math, or what?

Because it isn't intuitive. Same thing with sampling theory. People don't seem to trust things based on math they don't understand. Thing is, once you 'get' the math, it is quite beautiful.
 

Julf

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Even if you don't grok the math, it can be explained in basic principle with simple pictures so one can at least get the concept. Which should make it easier to accept the accuracy of the idea. Not to mention all the signal analysis that can be done getting correct results using that principle.
That would require the ability to adapt your beliefs based on facts.
 

fpitas

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It makes me want to make music that doesn't use tones :D
 

voodooless

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Even if you don't grok the math, it can be explained in basic principle with simple pictures so one can at least get the concept.
Veritassium had a nice video about FFT last week:


Turns out the algorithm (as well as the transform itself) was already discovered by Gauss, about 150 years before the official invention date. We should call it the Fast Gauss Transform :facepalm:
 

fpitas

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Veritassium had a nice video about FFT last week:


Turns out the algorithm (as well as the transform itself) was already discovered by Gauss, about 150 years before the official invention date. We should call it the Fast Gauss Transform :facepalm:
Yeah, all this stuff was discovered and proven hundreds of years ago. I guess some people just never got the memos, so they come bug us.
 

fpitas

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Galliardist

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Yes and no. I would say "no sound signature from a good DAC using the best filter algorithms available in that DAC". The problem is that DAC manufacturers feel compelled (for marketing reasons) to add all sorts of non-optimal filter alternatives.
Of course. The point is really that the blind test usually comes down to "when we remove every potential cause of two suitably accurate devices sounding different, then they sound the same".
That may seem dismissive, but we don't have to allow for audible differences other than those we know about from proper conventional measurements and understanding, and the damn devices still keep sounding the same.
 

Galliardist

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fpitas

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Ported

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That is exactly what the null comparator (link a few messages back in the thread) does. The results show the absolute difference, but that says nothing about if the differences are audible or not.
Right thanks for the info..
Complete conjecture on my part but it seems that this is the place where some kind of digital analysis is required .. i.e is there any repeated patterns in the differences that could be attributed to the 2 tested almost perfectly transparent devices somehow not being quite the same under real conditions... Could any repeated differences also contain clues to which sine waves make up these differences and at what strength? .. thereby adding to a possible describable signature difference. The strength aspect would set up a new debate as to if it's audible or not... What fun!
I have no access to su-9 to test anymore .. sent it back for reasons given .. maybe I will get Amazon to "lend me one" again!
I could do the test for the TV DAC v rme but if any of you were here and could not instantly tell the difference at levels moderate to loud then possibly I respectfully suggest you need to find another interest! Some such differences are clearly obvious... (Even to my wife).
 

Julf

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Complete conjecture on my part but it seems that this is the place where some kind of digital analysis is required .. i.e is there any repeated patterns in the differences that could be attributed to the 2 tested almost perfectly transparent devices somehow not being quite the same under real conditions... Could any repeated differences also contain clues to which sine waves make up these differences and at what strength? .. thereby adding to a possible describable signature difference. The strength aspect would set up a new debate as to if it's audible or not... What fun!
Something to be done once it has been shown that there actually are audible differences.
I could do the test for the TV DAC v rme but if any of you were here and could not instantly tell the difference at levels moderate to loud then possibly I respectfully suggest you need to find another interest! Some such differences are clearly obvious... (Even to my wife).
Oh, the standard audiophile "even my wife can hear it". :)

So, please tell us how you can tell if the differences you hear are because of some coloration in one of the devices, or just a level difference of a decibel or two? Human ears don't perceive small level differences as a difference in volume, but rather as a difference in the quality of the sound.
 

fpitas

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We keep going down this road every other thread. Someone thinks they hear something, and we should work hard to prove it.
 

voodooless

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I could do the test for the TV DAC v rme but if any of you were here and could not instantly tell the difference at levels moderate to loud then possibly I respectfully suggest you need to find another interest! Some such differences are clearly obvious... (Even to my wife).
To be fair, some TVs are known to do all kinds of processing before they output anything, even on the digital output sometimes. I wouldn't trust any TV to give decent audio, other than via HDMI.


 
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Exactly .. when the bass content is heavily bloomed and the high hats are almost non existent you don't need a blind test to tell ..
 

SIY

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Exactly .. when the bass content is heavily bloomed and the high hats are almost non existent you don't need a blind test to tell ..
In other words, you can’t tell without peeking. Otherwise, you’d actually have evidence by now to back up your unlikely claims.
 

ahofer

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Exactly .. when the bass content is heavily bloomed and the high hats are almost non existent you don't need a blind test to tell ..
Sometimes you do. It's extraordinary what selective attention and expectations will do.

But with TV DACs there is often some other processing going on that does affect sound. Even digital out (lossy resampling).
 

Owl

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My new Sony TV and 4k bluray player work excellent together for PCM pass trough via TOSLINK to an external DAC. I tried connecting the bluray player directly to the external DAC with the SPDIF output and there is no difference. My slightly older Sony TV and Panasonic bluray player didn't play as nice, so I bypassed the TV. Both bluray players outputting HDMI.
 
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