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John Curl's Blowtorch preamplifier part III
John Curl's Blowtorch preamplifier part III
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Old Yesterday, 03:10 PM   #8691
john curl is offline john curl  United States
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I get sad too. I just want to improve other peoples audio designs with what I have found works for me, if they are interested.
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Old Yesterday, 04:05 PM   #8692
BV is offline BV  Slovakia
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But yours impressions are non transferable, valid only for you. Because are highly subjective.
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Old Yesterday, 04:29 PM   #8693
hhoyt is offline hhoyt  United States
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John Curl's Blowtorch preamplifier part III
Quote:
Originally Posted by dadod View Post
Sometimes I am very sad reading this thread.
I share your disappointment.

I wish people making claims would provide data, or even a description of the mechanism behind their technology. They can't have just magically stumbled upon it fully developed while sitting on the throne, they have to have conceived of it theoretically before designing and perfecting it into an actual "thing." Consequently there is an underlying basis of operation which they could describe. John Curl's descriptions of his designs have contributed greatly to my understanding of amplifier performance as have others.

I think the root of many audio claims is related to the fact that 'hearing' is often misconstrued to mean 'responding to an air pressure variation on the eardrum', when in reality what we 'hear' is what our brains process and feed our consciousness. Something which is 'heard' is never, I repeat, never a raw sensory perception. It is always a perception processed by algorithms drawn from memory of previous sensory input. Indeed what we 'hear' can even be solely a product of memory, an expectation, other sensory input concurrent with the audio, or a combination of these factors. Emotional state is a strong contributing factor to the brain's perception of sounds. Listening to a movie soundtrack without the video is a very different experience than the sound when watching the movie, why is this? The audio should be identical, but why does it have a different 'feel'? Measurement tools would verify that all is identical, but our perception of it is not. Is this because the presence of the photons in the room change the characteristics of the air bringing the sound to our ears? Hey, I'm open to any provable idea, but I would place a very high likelihood it is due to our perception, not the raw sensory input.

I would never state that a person claiming to hear something is not actually 'hearing' something. Taking first the actual physical act of acquiring auditory sensory data; perhaps that person hears infra or super-sonic noises that others cannot. No two people have the exact same sensitivity vs. frequency curve, indeed the number of cochlear hairs and nerve endings vary between people. The attack and release sensitivity and time constants of the stapedius muscle differ greatly between people which can account for a physiological masking phenomenon (and is one of the reasons lossy compression doesn't work for everyone).

However my experience in audio leads me to believe the explanation in most cases for differing perception is related to the fact our hearing is part physical and part mental processing. Our brains can do wonderful things with the raw sensory input, just the fact that we have discrete frequency sensors yet we hear a continuum of frequencies is amazing! People with certain mental conditions can claim to hear voices and other phenomenon, and one cannot doubt they actually hear them, yet there is no air pressure disturbance being sensed. I can still hear a 24-year old Bonnie Raitt singing to me from ten feet away in my head like it was yesterday...yet it unfortunately only exists in my brain. However, any one telling me I am not 'hearing' it is wrong.

It is for these reasons, that claims of aural effects with no attempt to ascribe them to a physical process is pretty much a waste of time, at least on the internet. If someone has developed a technology which actually affects sound it can be demonstrated and sensed by others. If no others can sense it, then the claimant has a singular ability to hear in which case it applies to no one else, or the sound exists only in the mind of the claimant.

I'm not saying anyone here is doing this, but historically in the audiophile community I have found when people make claims they cannot support technologically and for which no difference can be heard by others, they end up just saying "I'm sorry you can't hear that" which is code for "I can hear better than you" accompanied by a disparaging look, and usually will refuse to participate in any form of comparison. This is not only unhelpful, it is not up to a person to disprove a claim made by others, it is up to the claimant to prove their claim.

It is in this type of situation where I have often conducted experiments by surreptitiously changing the demonstrations I was involved in, which was my own personal blind test of the claim and the claimant. As a single instance, when demoing directional speaker cables I was asked to connect them with the arrows pointing to the speakers, I instead reversed them. The claimant then began waxing poetic of how much more right this sounded. When told "whoops, sorry, they are backwards," he said, "you know, I thought something wasn't quite right...", and we "reversed" them (but once again did not) and he then stated that was much better. We did turn them around and I heard no difference either way, nor did any of the other engineers and 'golden-ears' present. I didn't bother correcting the rep since we wanted to carry the brands he represented, but we didn't purchase the cables. I am not saying there cannot be asymmetrical characteristics to cabling, indeed it is desirable in some situations, and as has been discussed here there are various reasons it can be so. I am just saying that the huge and phenomenally expensive zip-cord style speaker cables I was testing at that time had no directional characteristics. I'm not even saying this rep was dishonest, he could have thought he heard a difference in the tests he had participated in previously but had not done due-diligence to determine why. I have done testing like this to other claims as well and find it a useful way to separate the claim from the claimant.

Some may call this method of testing dishonest, but I disagree. If I am the customer, short of destruction I should be able to test devices and processes out in any way I wish to determine performance without the knowledge or interference of the seller. When performing true unbiased testing, one has to have tests to separate the variables involved: the technology, the claimant and your own perception.

Enough blathering, yes, I am avoiding housework. Back to...whatever it was we were talking about. How come no one took me up on the subject of DAC differences? There seems to be a lot of test data, I would appreciate first-person correlation of these with sonic attributes.

Cheers!
Howie
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Old Yesterday, 04:49 PM   #8694
Markw4 is offline Markw4  United States
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Howie,
I don't know that claimants need to have a theory. A process should do: "When I do 'this' I like the way it sounds and so do others." In other words, there should be sufficient information or some way to reproduce the experiment in order verify the claim. Theoretical justification is probably fine too, and may obviate the need for replication if the theory 'makes sense' to one educated in the arts. Otherwise, the theory may need testing too.

Also, even if theoretical justification attempt(s) by a claimant fail to pass expert validation, that does mean that some experimentally claimed phenomenon did not occur. It might only mean that the claimant is not an expert theoretician.

In some ways it may be better to discourage amateur attempts at theorizing. Once bogus theories come to be believed, attempts at correction by experts may elicit backfire effect, potentially worsening an already unfortunate situation.

Last edited by Markw4; Yesterday at 04:53 PM.
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Old Yesterday, 05:50 PM   #8695
RNMarsh is offline RNMarsh  United States
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Quote:
Originally Posted by Markw4 View Post
Howie,
I don't know that claimants need to have a theory. A process should do: "When I do 'this' I like the way it sounds and so do others." In other words, there should be sufficient information or some way to reproduce the experiment in order verify the claim. Theoretical justification is probably fine too, and may obviate the need for replication if the theory 'makes sense' to one educated in the arts. Otherwise, the theory may need testing too.

Also, even if theoretical justification attempt(s) by a claimant fail to pass expert validation, that does not mean that some experimentally claimed phenomenon did not occur. It might only mean that the claimant is not an expert theoretician.

In some ways it may be better to discourage amateur attempts at theorizing. Once bogus theories come to be believed, attempts at correction by experts may elicit backfire effect, potentially worsening an already unfortunate situation.


!

-RNM

Last edited by RNMarsh; Yesterday at 06:02 PM.
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Old Yesterday, 06:01 PM   #8696
hhoyt is offline hhoyt  United States
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John Curl's Blowtorch preamplifier part III
Quote:
Originally Posted by Markw4 View Post
Howie,
I don't know that claimants need to have a theory. A process should do: "When I do 'this' I like the way it sounds and so do others." In other words, there should be sufficient information or some way to reproduce the experiment in order verify the claim. Theoretical justification is probably fine too, and may obviate the need for replication if the theory 'makes sense' to one educated in the arts. Otherwise, the theory may need testing too.

Also, even if theoretical justification attempt(s) by a claimant fail to pass expert validation, that does mean that some experimentally claimed phenomenon did not occur. It might only mean that the claimant is not an expert theoretician.

In some ways it may be better to discourage amateur attempts at theorizing. Once bogus theories come to be believed, attempts at correction by experts may elicit backfire effect, potentially worsening an already unfortunate situation.
True, and well stated! I agree although amateur theorizing can be a start, and as long as people respect those skilled in the art's take on the issue with all due weight. Experience usually trumps guessing...

Cheers!
Howie
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Old Yesterday, 06:04 PM   #8697
john curl is offline john curl  United States
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Howie, am sure that I have been fooled too, in some situations. Still, if I and some other people, who seem to be my colleagues, hear a similar difference, I suspect that it is probably real.
Yesterday, I participated in an audio talk for the SF Audio Society, but before we started, a listening comparison was made from different vinyl cleaning machines on identical new recordings. To my surprise, EVERY repetition sounded different, not just in background, but in the timbre of the human voice on the recording. It was surprising, because I had never heard the recording before, and I sat in the middle, between the speakers, in the front row.
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Old Yesterday, 06:47 PM   #8698
hhoyt is offline hhoyt  United States
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John Curl's Blowtorch preamplifier part III
Quote:
Originally Posted by john curl View Post
Howie, am sure that I have been fooled too, in some situations. Still, if I and some other people, who seem to be my colleagues, hear a similar difference, I suspect that it is probably real.
Yesterday, I participated in an audio talk for the SF Audio Society, but before we started, a listening comparison was made from different vinyl cleaning machines on identical new recordings. To my surprise, EVERY repetition sounded different, not just in background, but in the timbre of the human voice on the recording. It was surprising, because I had never heard the recording before, and I sat in the middle, between the speakers, in the front row.
Hi John!

I would agree that something is going on if more than one person, unprompted hears the same thing. Exactly what is heard, and what it is due to are what interests me, which would require more rigor than can be established in a casual setting. We all have our strengths, and I understand you bring your impressive experience to bear with circuit design, and perhaps less so with other areas of expertise. In those cases we need other experts experiencing, analyzing and commenting on what is heard and possible causes.

Among us here JNeutron and some others would seem to have the best experiential base to evaluate physical phenomena.

Regarding your experience with record cleaning: I know exactly what you mean, I have noticed the same evaluating cleaners for radio stations. I attributed the effect to masking caused by surface noise phenomena. Once reduced or eliminated I could hear deeper into reverb tails and hear subtle harmonics of voices and instruments better, of course this was just my experience.

Cheers!
Howie
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Old Yesterday, 07:00 PM   #8699
RNMarsh is offline RNMarsh  United States
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Quote:
Originally Posted by john curl View Post
Howie, am sure that I have been fooled too, in some situations. Still, if I and some other people, who seem to be my colleagues, hear a similar difference, I suspect that it is probably real.
Yesterday, I participated in an audio talk for the SF Audio Society, but before we started, a listening comparison was made from different vinyl cleaning machines on identical new recordings. To my surprise, EVERY repetition sounded different, not just in background, but in the timbre of the human voice on the recording. It was surprising, because I had never heard the recording before, and I sat in the middle, between the speakers, in the front row.
hmmmm. do you mean that you listened to new uncleaned records and they sounded alike. and then cleaned each one on a seperate/different machine and relistened to each one?

Or was it the same record cleaned on different machines and listened after each cleaning?

I am concerned about the usual increase in distortion with each playing if it was the same record played after being cleaned with different machines.



THx-RNMarsh

Last edited by RNMarsh; Yesterday at 07:08 PM.
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