John Curl's Blowtorch preamplifier part III

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it might be that T and others are not lol, good on them and why not.
I never "LOL" when I read comments of listening impressions reports from other contributors. On the contrary.
I don't take-it for granted for any reason, if I do not have made the experience by myself. In this case, I am thankful that somebody had drew my attention to something... as long as it is not too surrealistic or in violation of verified laws of physics.
I will not follow the path of J.C. on the cable break-in or orientation of a conductor, or those mysterious Bybee devices ;-), which does not detract from the respect I have on many other points he underline.

If you want to know my position about you, if I found sometimes that you go too far to my taste in some poetic attitude about Audio, a taste for mystery ;-) I read often in an open mind attitude valuable and interesting comments under your signature. I hope some can feel the same about me ;-)
This said, I'm not sitting at the right of God, like pure objectivists seems to believe they are.
 
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Let's take an example. At the beginning of my carrer, in the years 70, we were using carbon layer resistors in the R&D department of the company I was working for. I found a big difference, trying metallic layers ones that were expensive at this time:


The difference between Carbon and metal film resistors is very easily measurable and is therefore firmly objective other than tube guitar amps which are carefully tuned for a particular distortion profile.
 
It seems to me more appropriate to use the measures to validate and explain our listening impressions and correct flaws. Not the contrary. What does not prevent that, the better is a factor to the measures, the better will be the result, but that does not tell everything: No way to chose a device on the simple read of its datasheet. It just help to eliminate obviously poor ones.
 
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I do not agree with so called "objectivists" of this forum, that believe everything is said by measurements and are strangely suspicious about "listening".
They presuppose that we are all stupid puppets, manipulated by evil salesmen of snake oil, hypnotized by their marketing pitch. I was shocked to read Mola-Mola's gibberish on their web page. Gourou Bruno P. ;-) being supposed to be more serious than that. Specially about its Class D amp, that are far to be the best amplifier that we can find on the market for the money, without wishing to be disagreeable !

Now who is being rude / provocative? Who called anyone a "stupid puppet"?

The only "suspicion" that comes with listening results is when they are not reproducible, or lack a serous attempt to remove cognitive biases.
Secondly, it is incumbent upon those who can apparently hear something to try and find a way of measuring it, so it can be validated by many. That's science. Unless they don't care, of course.
If I can't hear it, for example, perhaps because on this forum we are geographically well distributed (I can't listen to your system...), then if they want it to be more than an idle talking point they need to provide hard data.

Of course, if they just want to enjoy what they hear, that's not a problem.
 
That's science.
No, that's only technology.
(Sorry, but no surprise, that you felt targeted.)

To ask others for results of measurements they have not obligatory kept is to ask them to work for you for free.
Can-i remind you that this forum is called "Do It yoursef" ?
Sharing listening impressions is better than sharing NOTHING.
On my side, when I'm not interested by something (like sound of cables*), I do not make any comments.
If I am interested, I make both listening (if I can) and measurements to confirm or infirm a "claim".

* On this example, I could explain in a very "scientific way" why and how to get rid of the problem.
 
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No, that's only technology.
(Sorry, but no surprise, that you felt targeted.)

To ask others for results of measures they have not kept is to ask them to work for you for free.
Can-i remind you that this forum is called "Do It yoursef".
Sharing listening impressions is better than sharing NOTHING.
On my side, when I'm not interested by something (like sound of cables), I do not make any comments.
If I am, I make both listening (if I can) and measurements to confirm or infirm a "claim".

A fundamental aspect of science is reproducibility.
Not asking anyone to work for free. Just don't claim something is "true" when you mean "I like". Otherwise it's fine, a fireside chat.
 
A fundamental aspect of science is reproducibility.
Again, "audio" design is not science, only technology.
Having worked in R&D departments and in audio industry near all my professional life, being paid for my little technical competencies and verified, by results, correctness, do-you really think you can teach-me something on this point of good methods ?
Nb: About "listening impressions", the same law "reproducibility" is a requisite.
 
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Only pseudoscience, you are a one of a kind Tournesol.
For you wow!
What about the component components problem? As such,
there seems to be no law. Those components that
are outside the cup, are protected from
from the air, while those who are inside it
side, more exposed to swirls
than the siphoning and do not leave
easy to fly, assuming the fan
with no rampage. It is magical to see what
ropiiri quietly and gently just rise
the printed circuit board.

Have you ever met the cal?
The housen 500 mx on fire riecu!
Medication time gentlemen.
 
Sorry - I bow to your undoubted expertise. The rest of us know nothing in comparison.
That's enough, gpauk. Strange way to interpret my words: "little technical competencies".
An other example of your " rude / provocative" attitude.
Contrary to you I don't give lessons to others.
Just trying to share what I had learned or experienced in my life on the subject, and thankful to others sharing their own which are, in essence, different from mine.
We all have a lot to learn, few to teach.
And, sorry, but this forum is nothing more, indeed, than a "fireside chat".
NOTHING more and certainly not an academy of sciences.
Have a good day.
 
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I have mentioned M-Noise several times now and no response to this most useful test signal which neatly triggers excess noise behaviours,.... 'perles avant porc' ?.

I downloaded the M noise, it looks simply like pink noise with scaled and filtered random impulses added. Whatever the process the probability density function underlying it would not be of a physical random one IMO nor would it map to much music, except mine of course.
 
I never "LOL" when I read comments of listening impressions reports from other contributors. On the contrary.
I don't take-it for granted for any reason, if I do not have made the experience by myself. In this case, I am thankful that somebody had drew my attention to something... as long as it is not too surrealistic or in violation of verified laws of physics.

I made joke in defense to CF impolitely questioning my sanity (in both French and English thank you) by saying that I am unencumbered by substances and that you and he may not be able to say the same....you did mention liquid lunch earlier, that's why I added 'lol'.
Anyway, we are on the same page.....I do take note of what is said by professionals, owners, reviewers, constructors, the man on the street etc and you....I do not immediately discount 'odd' descriptions but instead may 'read between the lines' to understand the underlying of what is being said.

I will not follow the path of J.C. on the cable break-in or orientation of a conductor, or those mysterious Bybee devices ;-), which does not detract from the respect I have on many other points he underline.
I listen to what JC says and I learn.....he drops pearls of wisdom along the way as so do you very often.
JC mentions cable direction and BQP, both items I concur but perhaps I have investigated further.
Cable break-in not so much, but I do observe short term system break-in behaviours that are driven by program and program embedded noise and comes down to the first large/full amplitude peaks setting a new system behaviour, and erasing previous (temporarily memorised ?) behaviours.


If you want to know my position about you, if I found sometimes that you go too far to my taste in some poetic attitude about Audio, a taste for mystery ;-) I read often in an open mind attitude valuable and interesting comments under your signature. I hope some can feel the same about me ;-)
This said, I'm not sitting at the right of God, like pure objectivists seems to believe they are.
Yes I know that some of the information I convey is seemingly 'far out' but that opinion depends on the 'education', experience and standing of the recipient of this information.....my 'Grasshopper' allegory is intended to convey this concept.
I have commented to friends when demonstrating my filters that this concept is seen as impossible and imaginary by members of this forum.....this is greeted with laughter and comments regarding sad ignorance of those who are inexperienced but nevertheless are opinionated and 'knowing it all'.
So T, like you I must have physics explanation and objective confirmation, but sometimes the accepted 'laws' and theories do not fully fit the subjectively observed.
In the mean time I have no interest in 'poetic' attitude to audio, but I have learned to trust my ears and this drives my researches that mere meter watching would have discouraged long ago.
Yes, none of us are 'audio gods' and has all the keys, each of us has knowledge and experience that another does not but collectively the intelligent minds overlapping here can help to piece together this jig-saw puzzle we call audio.


le égard.
Dan.
 
I downloaded the M noise, it looks simply like pink noise with scaled and filtered random impulses added. Whatever the process the probability density function underlying it would not be of a physical random one IMO nor would it map to much music, except mine of course.
:)
Just reading at a vu-meter playing some music seems enough for erasing your "IMO".
Impossible to mimic-it with a constant level signal.
 
I do not agree with so called "objectivists" of this forum, that believe everything is said by measurements and are strangely suspicious about "listening".
They presuppose that we are all stupid puppets, manipulated by evil salesmen of snake oil, hypnotized by their marketing pitch. I was shocked to read Mola-Mola's gibberish on their web page. Gourou Bruno P. ;-) being supposed to be more serious than that. Specially about its Class D amp, that are far to be the best amplifier that we can find on the market for the money, without wishing to be disagreeable !
No, that's only technology.
(Sorry, but no surprise, that you felt targeted.)

To ask others for results of measurements they have not obligatory kept is to ask them to work for you for free.
Can-i remind you that this forum is called "Do It yoursef" ?
Sharing listening impressions is better than sharing NOTHING.
On my side, when I'm not interested by something (like sound of cables*), I do not make any comments.
If I am interested, I make both listening (if I can) and measurements to confirm or infirm a "claim".

* On this example, I could explain in a very "scientific way" why and how to get rid of the problem.
You seem unhappy with this forum. Have you thought about searching for other forums that you would be happy with?
 
I downloaded the M noise, it looks simply like pink noise with scaled and filtered random impulses added. Whatever the process the probability density function underlying it would not be of a physical random one IMO nor would it map to much music, except mine of course.
The sequence is 53 seconds and there is mention that it can be looped indefinitely, but no mention of real randomness.
There is mention of it being mathematically derived -
Meyer Sound has introduced M‑Noise, a new test signal that will promote standardized measurement of a loudspeaker system’s maximum linear output. A mathematically derived test signal that effectively emulates the dynamic characteristics of music, M‑Noise enables a far more accurate measurement of a loudspeaker system’s linear peak SPL in any application requiring reproduction of musical content.
The mathematical formula for generating M‑Noise was derived following extensive spectral analysis of a wide variety of music program material. In particular, the analysis measured the varying crest factors in music, and how these measurements compared to pink noise (crest factor is the difference between the average and instantaneous peak levels of a signal). It was discovered that the crest factors of music and pink noise were similar at frequencies below 500 Hz, but with music exhibiting a steadily rising crest factor at higher frequencies.
 
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My investigations say that the presence of non magnetic forms surrounding or in proximity of system conductors and transducers (magnetic or electric) will cause change in nature of system noise floor. The answer will be buried somewhere deep in atomic theory, or perhaps in Maxwell's full equations, the answer is or will be somewhere. The influence of particular materials/compounds is on spectrum and dynamics of system noise floor, and according to particular material/compound can be "dominant sounding" (and identifiable). Amplitude and dynamic characteristics of the system noise floor is in large part what gives 'voicing' or 'house sound' and we have all historically experienced identifiable house sounds from the major (mostly asian) domestic audio manufacturers....look closely and the common factors and also the differences of such equipment are laid bare to the eyes (and to the ears).
Dan.

I think you are saying that different resistive materials have a different noise component and that there is a strong noise modulation with signal with different materials. This sounds interesting but should be pretty easy to test for with instruments, not just ears. I know some resistors have a lot of added noise when current is passed through (e.g. carbon) but far less with metallic resistors.

Mercury should be very low noise and while higher resistance than silver or gold it will be constant over millions of operations. The datasheet I checked suggested 50 milliOhms of contact resistance. For silver or gold contacts there still is a contact breakdown process needed for electrical connection. I believe mercury wetted relays don't have that issue.
 
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