John Curl's Blowtorch preamplifier part II

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We cannot tell exactly what subjective effects some changes applied to a signal will produce in our brains. And that is the reason why "Audiophiles" pretend that measurements don't tell everything.
But there is something obvious, with our actual technology : Any real change at the lowest level applied to a signal witch can have an audible effect will be put in evidence with accurate measurements.

The mystery, for me, in this boring Bybee story, is: How some famous audio designer, supposed to have a scientific basis in electronic, can believe in snake oil, like Bybee blabla, and use to spend its time in 'burning' cables during weeks or mark them in order to mount them in a dedicated sens in his preamplifiers.
The only result produced by such asserts is the question i ask myself about his competency or honesty, while in the same time, (for what i know of his schematics) the rest of his work is compliant with the 'state of art' of electronic. Yes, a big mystery for me.
 
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clifforrest said:
JC does himself no favours (British "u"!) with his blunt provocative style and stubbornness,
thats just the way its spelled correctly, it has no nationality ;)

dont forget the ceaseless namedropping and belittling equipment quality/hearing acuity. All pretty stock standard and boring excuses for evidence zero.

@ kgrlee: its a bit of a broken record mate, we got the message, I agree John has in the past made ridiculous statements evoking sorcery, equally tired and cliched anecdotal reports/excuses against the many legged audio creatures at the 7th, particularly apparent when Scott is in the 'room'.

its hard to fathom the alignment with these silly things that can be generously described as having effects that are equal in scale (rather than effect) to the the quantum level they are said to operate at...

Sometimes he appears to be just making stuff up as he goes and says out loud that its a chore to have to provide something by way of proof of his statements.... Given the general population of this thread, this often comes across as actively trolling for a reaction; usually accompanied by some sort of secret suicide pill sauce elucidation.

We are left with self delusion or deception as options and that is indeed a sad state of affairs for such a well respected designer (even the majority of his detractors (and indeed myself) are accepting of this on the whole). he even actively stirs it all up on a regular basis....baffling.

etc etc we/I get that, but you are getting nowhere and its just becoming painful to watch; you are only doing yourself a disservice.
 
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John throws out clues not answers, his retorts to question are meant to incite research, frustrating if you want to be given the answers ...

I do wish the over the top disrespectful bashing would cease thou ....:(

As to the BQP and after doing some research on it , I'm with Sy , well until i can hear this sonic marvel at work myself .... :)
 
John throws out clues not answers, his retorts to question are meant to incite research, frustrating if you want to be given the answers ...

I do wish the over the top disrespectful bashing would cease thou ....:(

As to the BQP and after doing some research on it , I'm with Sy , well until i can hear this sonic marvel at work myself .... :)

I speak specifically of backing up his own sometimes dubious (and almost always deliberately vague) pseudo technical assertions, not handouts of secret knowledge...
 
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Can you describe the model or make up a model that predicts the thd of an electrolytic or a ceramic (non npo)? Thx-RNMarsh

That would be my only purpose in doing all the measurements. It's a lot of work and no one so far has bothered or proved it can't be done. To Jan's simple point folks soft petal the fact that if AC coupling components are chosen to have little or no AC across them there is little or no distortion. A small second order non-linearity produces a small DC component, hardly the same as Bateman's 2V AC riding on 20V DC. How about comparing 40V p-p AC to 2V AC. It's just like no one being interested in just how much a simple TC and thermal time constant would predict (probably) most of the resistor distortion measurements.

In many cases there is not much interest in maximizing the performance out of ordinary components, instead bespoke or exotic components get put in every socket. So again sorry if I am hard on fashion audio claims.
 
I do wish the over the top disrespectful bashing would cease thou ...
Most of us takes no pleasure to contradict anyone. The only reason we are here is to discover new things from other's experiences and share the ones we had learned and experienced. And exchange in a friendly atmosphere on a subject witch passionate us.
John is a famous designer. This gives a significant weight and responsibility on what he publish.
When John, unfortunately, walk on the obscurantist side of the road (and we all know the dangerous consequences it can lead to) , it is OUR responsibility to less knowledgeable visitors to refocus the debate in the correct scientific direction. And you will see that, in this matter, EVERYBODY with enough electronic background, here, agree on the same technical evidences and methodology.
There is other famous designers, here. No one had to suffer the same controversy. Because they are technically irreproachable. We can have different tastes, we can chose different ways to reach the same goals, we all agree on the maths.

In many cases there is not much interest in maximizing the performance out of ordinary components, instead bespoke or exotic components get put in every socket. So again sorry if I am hard on fashion audio claims.
+1
 
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If even-order harmonics derive from even-order distortion (they need not, although usually they do) then the even-order distortion will create a DC term too. This disappears completely at the first coupling cap or transformer encountered by the signal. So DC does not necessarily imply even-order distortion; even-order distortion does not necessarily imply DC. Similarly for any asymmetric waveform: DC and asymmetry do not necessarily accompany each other. Having said that, I'm not sure why we are discussing such elementary issues.

I don't either, but twice this week "asymmetrical waveforms have DC" was stated as an obvious fact. In xDSL as in audio large plus or minus crest events are not matched by the opposite polarity but the time average is 0 (especially in xDSL where there is complete galvanic isolation on both ends).

The case is DC component on the primary of psu mains xformers .
And Scott, average may be 0 indeed over a considerable time period but for small periods it certainly may not be. During this time then, the xformer saturates.
In total, my understanding is that even harmonics on mains are present only when waveform is asymmetric (and their presence is a good way to test for mains wave asymmetry ).
This asymmetry -for the time it occurs- creates a DC component . I am in agreement (for the first time) with JC here.

NO, when second harmonic is generated from a primary sine wave, it CREATES A DC OFFSET as well as adding second harmonic. This is WHY we sometimes have DC on the AC power line, and this then makes toroid transformers BUZZ. There are online fixes for this, check it out.

Online fixes in these two threads:
"]http://www.diyaudio.com/forums/solid-state/2080-dc-filter.html#post15943

http://www.diyaudio.com/forums/power-supplies/161428-variations-dc-main-filter-against-buzzing-toroid-transformers-what-right.html#post2087375

If one objects to presence of DC at times on utility’s mains AC or has another explanation of it’s generation there, please explain.:)

George
 
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Well, that's one for the 'books': NAMEDROPPING
I'm sorry, but I can't help it, because these are the people that either I or my colleagues have worked with over the decades.
Usually, these 'famous' people were or are my colleagues, many are not still alive, and I have had serious interaction with them at some point in my audio history.
Let me give you an example:
I met Richard Heyser in 1968 when I was sent to the AES because I worked in the Audio Department at the time, and I wanted to go.
I can't remember how I got introduced to him, but it was probably through Paul Klipsch, because I knew him previously as I used to sell K-horns part time at a hi fi store, while working my way through college. In any case, Richard, Paul, and I wound up during a break in the proceedings in Paul Klipsch's room where we shared a few shots of premium Kentucky bourbon together, the bottle brought especially by Paul for the occasion.
We got together for dinner, etc for years, and I would call him on the telephone when I had a technical question like: What is time delay, really? Is it phase delay, group delay or is there some sort of 'real delay'? How could to signals, with real time delay come together and LOSE their respective time delay? That was a question I had for him in 1977, when I was working on the Symmetry Xover. He gave me the answer, at least to the second part, at the time.
Visiting my office that I had in Berkeley for about 12 years was:
Dr. Malcolm Hawksford
Dr. Vandenhul
Michael Gerzon
Dr. Diamond
And a great number of others.
The rest, I have met on their home turf, being that Norway, Denmark, Finland, Great Britain, France, etc. , or at AES Conventions in either Europe or the USA.
The two most brilliant people in audio that I have ever encountered were:
Richard Heyser and Michael Gerzon. I will always hold them in my memory as such.
Now is there anything wrong with what I just said? Am I supposed to hide my connections, behind some veil of intellectual modesty? That's one for the etiquette books! '-)
 
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Real music has a dynamic DC component just like Richard says. It has been measured, and written about. It is the FUNDAMENTAL factor in detecting dielectric absorption in Walt's, Scott's and my testing of caps, back in the middle '80's.

Why when I showed how Peases' linear model could be used to fit the data to an arbitrary amount, no one was very interested.

Richard note, I had forgotten about this. I was interested in showing how to use our bridge to build a capacitor model based on Peases' R/C ladder model. Unfortunately no good story, no "memory", unknown distortions, you know how it goes.
 
It is NOT PEASE'S MODEL. It derives from Dow, et al, from analog computers in the 1950's. One day I will again find the 1985 letter that you sent that shows the DIFFERENCE between two caps, one with the 'Pease model' added in, in a computer simulation that you did then. You won't mind, will you? Do you refute your earlier analysis?
 
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Thanks Dan for your comments. I don't like 'fashion' either. Dr. Dree's headphones are a good example. I also know the people who work behind the scenes, and while they are nice to me, and technically capable, they are VERY CYNICAL about audio quality, and it does rub me the wrong way. In fact, I am going to have lunch with them, today! Can't pass over a home cooked meal! '-)
 
A typical asymmetric sound waveform (speech, word "below"). Still, only 0.006% DC. Some DC may be found over very short time passages. Some DC resulting from asymmetry may be found in Telarc 1812, short time, again.
 

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