John Curl's Blowtorch preamplifier part II

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Personally I believe feedback amplifiers sound better than zero feedback because when the electrons go around the loop they arrive a little bit behind the input signal.

This directly leads to a slight echo which makes the amp sound more spacey.


Now, if you use copper wire, the speed of the electrons is slightly slower than silver. Hence in my experience, copper sounds better because the feedback echo is bigger. Note that in high feedback amplifiers, the feedback can go around the loop many times. So, I am in disagreement with Martin Coulombs on this apect of feedback.

I think this was also what MOH was alluding to in his paper from the 'Essex Echo'.

Anyway, let's keep working at this because we will find new materials, or new ways of making cables that will give bigger feedback echo's and hence spacier sound.

For now, I need to get back to my scotch!
 
The "burn-in" thing signals, to me, that the materials used in the construction have various internal stresses from being bent into shape, moved into place. Those stresses need time to stabilise, which may cause audible artifacts, hearable by some ...
I can understand the changes in an electro-chemical capacitance done after burn-in. And can measure the changes. But a wire ?
 
All I know is what I have heard.

All you know is what you perceived, which as has been well known and well established for many decades is not always the result of what is actually heard.

"High end audio" has such a deep, pathological denial of this reality they look like a bunch of adults living in the fantasy world of a five year old. And really, there is no fundamental difference between believing silver is audibly different from copper than believing in Santa Claus.

se
 
Personally I believe feedback amplifiers sound better than zero feedback because when the electrons go around the loop they arrive a little bit behind the input signal.

Electron drift is literally slower than a snail's pace. Unless the loop is exceedingly microscopically small, you could never have feedback in the first place. Or does Santa Claus deliver the electrons back to the input?

se
 
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You still don't get it, your, Walt's and John's DA measurements are just fine it's just that in the exact application context the errors are trivial. Frankly after all these years I thought you guys were fussing over .02dB deviations from RIAA, I didn't know any better.

You forgot to add.... IMO.

I completely agree that DA causing .02dB level variation is not significant. I get it. How many more in a whole typical system give >.1dB variation? How many? Lets find out.

The waveform shape change to transients and the THD numbers of polar caps with sine waves that I see then and now are significant --- IMO. And that is just a single part and not several in a system..... I have pressed this point often... we listen to the entire system of parts not just one of them. So, why do we seperate out a single part or piece and make judgment on the whole? That I do not get.

[In digital, that way is going to be a disaster.... with interfacing induced jitter ignored, for example, and other system related causes of distortions.]

But, the polar cap THD seems to be the worse. What about IM of the polar cap.... anyone doing measurements that way? Lets find out.



THx-RNMarsh
 
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Hifi "objectivists" have such a deep, pathological denial of this reality they look like a bunch of adults living in the catechism class for five year old. And really, there is no fundamental difference between believing blind in a so calling "science" than believing in Santa Claus.
Note that, if they had not verified 1/1000 of what they are taught, they *believe* in it the same way than inquisition with Galilée.
And this "integrism" is anything but scientific.
 
I can understand the changes in an electro-chemical capacitance done after burn-in. And can measure the changes. But a wire ?
A wire is often not just a wire, it has at least a layer of insulation around it, in contact with it, a different material from the conductor. Yes, a perfect "insulation" will mean zero impact, but are the plastics, etc, actually used 100% benign in the audio world, at all times? Again, I use simple stuff, I don't want fussing to come into it - we have enough troubles elsewhere! ... :D
 
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Hifi "objectivists" have such a deep, pathological denial of this reality they look like a bunch of adults living in the catechism class for five year old.
And really, there is no fundamental difference between believing blind in a so calling "science" than believing in Santa Claus.
Note that, if they had not verified 1/1000 of what they are taught, they *believe* in it the same way than inquisition with Galilée.
And this "integrism" is anything but scientific.

Right on. Science has advanced more by empiricism than anything else.
Remember Edison, or read Karl Popper?
 
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All you know is what you perceived, which as has been well known and well established for many decades is not always the result of what is actually heard.
The easy trick, which I always use, is "difficult" recordings - a good example is a Harry James "roughie" I just listened to - this is big band sound going at a 100 miles an hour, extremely dense, plenty of media defects also there. If a system has a "brightness" problem this will be impossible to listen to, will send you screaming from the room - OTOH, if the system is 'correct' then it all falls into place - it becomes a very intense, pleasurable listening experience.

So much can be quickly learnt just by using the right recordings ...
 
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How many RIAA networks are there in a whole system? Might want to read what he actually wrote again.

se

cute. hahahahaha. But glad you asked for clarification:

How many polar caps could be found in a typical audio system is My point not his. Back then or in some Japanese brands now? The total we listen to is what we need to know and test for.

A MC pre-pre could have 2-3, the LP preamp could have 2-3 and the line stage could have 2-3 and the power amp could have 1,2 typically.

What is the cap total affect on THD of those in the system? Lets test it that way and find out the 'real' magnitude and if it exceeds a reasonable detection threshold.

What is the best way to do it in SIM? Say, 6-10 polar caps?

-RNM
 
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The easy trick, which I always use, is "difficult" recordings - a good example is a Harry James "roughie" I just listened to - this is big band sound going at a 100 miles an hour, extremely dense, plenty of media defects also there. If a system has a "brightness" problem this will be impossible to listen to, will send you screaming from the room - OTOH, if the system is 'correct' then it all falls into place - it becomes a very intense, pleasurable listening experience.

So much can be quickly learnt just by using the right recordings ...

I hope Santa Claus is good to you this year.

se
 
cute. hahahahaha. But glad you asked for clarification:

How many polar caps could be found in a typical audio system is My point not his. Back then or in some Japanese brands now? The total we listen to is what we need to know and test for.

A MC pre-pre could have 2-3, the LP preamp could have 2-3 and the line stage could have 2-3 and the power amp could have 1,2 typically.

What is the cap total affect on THD of those in the system? Lets tests it.

Knock yourself out. We'll await your report.

se
 
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