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John Curl's Blowtorch preamplifier part III
John Curl's Blowtorch preamplifier part III
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Old Yesterday, 07:57 PM   #29761
gpapag is offline gpapag  Greece
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John Curl's Blowtorch preamplifier part III
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you should learn, Scott
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To The Stars Academy

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Old Yesterday, 08:22 PM   #29762
RNMarsh is offline RNMarsh  United States
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Originally Posted by Jakob2 View Post
It could be due to noise-shaping, just a single tone is needed. Never underestimate the manufacturers creativity, muting the DAC output to pretend an even higher (at least at a first glance) S/N ratio, if no signal is presented is/was a common choice.

Without informations about the specifics of the implemented cirtuitry, it's hard to say.
Additional measurements could reveal if the noise distribution depends on the signal.
It seems like a really bad idea. Especially if you have to listen to music with that going on.

But its quite clever as it doesnt show up in standard test procedures for S/N.

-RNM
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Old Yesterday, 08:26 PM   #29763
Evenharmonics is offline Evenharmonics  United States
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Originally Posted by Markw4 View Post
Jakob2 was quite understandable IMHO. Not word salad or FUD at all.

The way it looks from here is that a few people are intolerant of things they don't understand, like science outside of physics.
Just as PMA pointed out in the quote below.
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I do not understand these hobby stereotypes and superstitions.
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Originally Posted by Markw4 View Post
For people who have studied a lot about perceptual testing, the above assumptions may or may not be considered reliable. It depends on a lot of unstated details about the purpose of a particular listening test, exactly how the test planned and conducted, how many test subjects are used, how results are interpreted, how replicable the test is, etc.
Does the same apply to subjective listening tests such as the one you and RNMarsh did when you went over to his place to listen to an upgraded DAC earlier this year?

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Jakob2 is the closest we have to an expert in perceptual testing (and will do quite nicely),
Who gets to determine that, someone with qualification on other people's level of expertise?
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Old Yesterday, 10:45 PM   #29764
simon7000 is offline simon7000  United States
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Originally Posted by scott wurcer View Post
Profound insight, I would never have known. I know Rich, are you sure he didn't think he was talking to someone that does not know the basic issues?
Ah the Scott I have come to know and love. Pretty sure he has a clue who I am. Of course you can always ask him. Do you need his email?
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Old Yesterday, 11:25 PM   #29765
1audio is offline 1audio  United States
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John Curl's Blowtorch preamplifier part III
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Originally Posted by RNMarsh View Post
It seems like a really bad idea. Especially if you have to listen to music with that going on.

But its quite clever as it doesnt show up in standard test procedures for S/N.

-RNM
One standard test that would show issue's with noise is the -60 dB dynamic range test with a tone looking for thd+n.
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Old Today, 03:56 AM   #29766
RNMarsh is offline RNMarsh  United States
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Originally Posted by Evenharmonics View Post

Does the same apply to subjective listening tests such as the one you and RNMarsh did when you went over to his place to listen to an upgraded DAC earlier this year?
The same applies. If you are doing a scientific study. We were not.

We agreed about the character of the sound as we heard it. Thats all we said.

If a tone control sets highs boosted and i listen and say it sounds bright. Is that scientific study?

Its just what we heard and described it. And we both agreed on what was heard and its character.


-RNMarsh
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Old Today, 04:08 AM   #29767
scott wurcer is offline scott wurcer  United States
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Originally Posted by simon7000 View Post
Ah the Scott I have come to know and love. Pretty sure he has a clue who I am. Of course you can always ask him. Do you need his email?
Did he offend you by saying something like you can't make a 1nV amplifier with a 1K source impedance? People have a lot of distractions in a public forum, I'm sure he had no intention of offending your intelligence.
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Old Today, 04:32 AM   #29768
Evenharmonics is offline Evenharmonics  United States
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Originally Posted by RNMarsh View Post
The same applies. If you are doing a scientific study. We were not.

We agreed about the character of the sound as we heard it. Thats all we said.

If a tone control sets highs boosted and i listen and say it sounds bright. Is that scientific study?

Its just what we heard and described it. And we both agreed on what was heard and its character.


-RNMarsh
Quote:
Originally Posted by Markw4 View Post
In other words, all the details matter. It is a gross oversimplification to rely on blind or sighted as all there is to it. Its something we humans tend to get wrong when we don't have expert knowledge of perceptual testing, or for that matter any other complex scientific field outside of our own area(s) of expertise.
I wonder if you both agree that it's something both of you've got it wrong because there is a tendency of it.
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Old Today, 04:57 AM   #29769
simon7000 is offline simon7000  United States
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Originally Posted by scott wurcer View Post
Did he offend you by saying something like you can't make a 1nV amplifier with a 1K source impedance? People have a lot of distractions in a public forum, I'm sure he had no intention of offending your intelligence.
No. Not even an issue in the particular item.

BTY at the AD room the fellow I spoke to was unfamiliar with you or your work.
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Old Today, 07:27 AM   #29770
indra1 is online now indra1  Indonesia
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Originally Posted by Markw4 View Post
... When we say a listening test is blind or sighted, there are some unstated assumptions commonly associated with those terms. We may tend to assume sighted means a listening test must necessarily be unreliable and blind means that a listening test is reliable (blind and level matched, you know). ...
Stereophile Carver challenge is a known published article show that some people, even with a certain bias, are genuinely able to hear a non difference on a sighted test. Perhaps it is a matter of skill. It is nice if a training program or a somewhat structured guideline exist so that more people (who are willing and in command of adequate means) can learn how to become more able to do so.
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