This is not the first time I say it, you must be the forum member who most help people and correct mistakes and this seems to me very laudable.
I respect you and I admire your amazing capacity to answer about almost any topic, fast and accurately, and I always say that you are one of our superheroes on the forum, the reference and the last resort.
However, this time you disappoint me, again.
On post#201 you "corrected" my "mistake" and you did an assertion, and so far you are still eluding my request about your assertion, and now finally you answer me with another member's answer which I had already seen before !
Without any intention to offend you, this is not intellectual honesty, if you are not able to give a proper answer, you are not able to correct the mistake. IMHO
And for my mistake, mind you that I found evidence of mechanical, thermal and optical anisotropy on the direction of rolling, in semi-crystalline polymers, and maybe, just maybe, I could be right after all.
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Let's see this evidence. It's odd that you can't afford basic distortion measurements, but you can afford the rather specialized equipment it takes to do measurements of mechanical, thermal, and optical anisotropy.
You also need to get a better handle on what "semicrystalline" means. Especially as it relates to scale. Start with the question, "Why is it transparent?" The problem is, if I may be blunt, that you have to be willing to discard most of what you know that isn't so in order to build the knowledge base that it will take to understand what the correct answers are. That's one reason I suggested that you actually do some distortion measurements- if they do not give you the results that your mental model predicts, that's the only thing which will induce you to abandon your mental model and get a fresh start down the correct path.
edit: And I should add that the rolling direction is normal to the applied field, so doesn't have much relevance to capacitor action.
this is a diy'ers forum, many here build amps and then go to the next one...
so i wonder for what prupose poppilin would like to argue "theories" ad infinitum....
i still can build amps even if i have no idea about.....
even if he's right, there are no awards to be granted, not even a lollipop....
so i wonder for what prupose poppilin would like to argue "theories" ad infinitum....
i still can build amps even if i have no idea about.....
even if he's right, there are no awards to be granted, not even a lollipop....
What makes this a great forum is that dictatorship of majority is allowed to be questioned by dissidents.this is a diy'ers forum, many here build amps and then go to the next one...
so i wonder for what prupose poppilin would like to argue "theories" ad infinitum....
i still can build amps even if i have no idea about.....
even if he's right, there are no awards to be granted, not even a lollipop....
In the following learning proces one can sharpen his mind and come to new knowledge (vs repeating the same exercise).
{hurray, we came second!}
C1 = 1000 µF / 16 V Electrolytic
C2 = 100 nF / 63 V MKP
C3 = 1.5 µF / 400 V MKP
a) bypassing one cathode lowers impedance of both tubes, but equally?
b) why not applying an 'ideal' load of 7K5 (if my math is right)?
My setup works ok too, when I obtain an audio taper pot
An externally hosted image should be here but it was not working when we last tested it.
c) What do you experience changing your setup for mine?
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Thank you very much, I really appreciate your support, and encourages me to continue.
I can't to know it without make some calculations first, sorry, however the answer is here
How to Gain Gain - A Reference Book on Triodes in Audio Pre-Amps
Very complete and profound, but with a horrible notation that makes difficult even the easiest calculations.
b) why not applying an 'ideal' load of 7K5 (if my math is right)?
My setup works ok too, when I obtain an audio taper pot
An externally hosted image should be here but it was not working when we last tested it.
Seems to me a very good idea, lower distortion with same order output impedance, and lower noise, three birds with one stone!
On the other hand, to obtain comparable frequency roll off, you must increase the value of C1 about one order of magnitude.
As I build all my amps/preamps with epoxy-glass PCBs, I will do some simulations first, because I think it deserves a serious try.
However I must confess that scares me a bit to put a 10 µF/400 V capacitor.
Does the validity of an answer depend on who says it? As I have only limited personal knowledge of fundamental research on dielectrics (i.e. small, but non-zero experience) any answer I give will essentially have to be a quote from someone else I trust: a textbook, trusted website, or trusted forum member.popilin said:
A standard technique which seems to be used on here by some, including you, is to make an incorrect statement based on misunderstanding and then demand that others prove that it is untrue. This is not a helpful way to advance knowledge, or to acquire existing knowledge. I have told you, and others have told you, that anisotropy and hysteresis are unrelated phenomena. These are facts. It is for you to defend your speculation, not for us to prove you wrong. So far your defence has serious holes.
I wonder who are the 'dictators' and who are the 'dissidents'? 'Dissident' is a word which should be reserved for those who have carefully considered and understood the accepted wisdom and then decided for very good reasons to reject it; not those who simply haven't bothered and merely assert without evidence that they don't like reality.disco said:
Two reasons
1) Improve the performance of my amps/preamps.
2) Equations are my vice.
8.6766×10^49 angels ?
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I already said it, but seems to me that nobody hear me, so, I will repeat it again
In ferromagnetic materials, the relation between B and H exhibits both nonlinearity and hysteresis, B is not a single valued function of H, magnetic anisotropy is a prerequisite for hysteresis in ferromagnetic materials.
Without magnetic anisotropy, a ferromagnetic material would be superparamagnetic, and as you must know, ideal superparamagnetic materials have not any hysteresis loop which means coercivity become zero.
Then, in this case, anisotropy is a necessary condition for hysteresis, and magnetic permeability must be a tensor.
Over the years, a lot of effort was did to develop simplified models for permeability to avoid the use of tensors, and fortunately those models work, and maybe this fact is the cause of your false assumption/misunderstanding.
I am working to prove that the analogy for dielectrics is valid, at least for some particular cases.
If I realize that I am wrong, I promise I will apologize publicly, because in addition that I am a TV repairman, also I am a gentleman.
Without any intention to offend you, but if yourself ignores the fact that dielectric absorption and dielectric hysteresis refer to the same phenomenon, let me say that your understanding about dielectrics is not as deep as you believe.
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Well put. I was thinking in line of what is demonstrated here. Different viewpoints are tolerated as long as not sold as truth. I know plenty of boards that don't allow for that space, so people leave burnt. Call me mellow
This is that people said, blind test, assay-error
It is not like crazy winding transformers or build blindly capacitors. Here people can learn the molecular and physical essence of what we see then reflected in the quality of sound. If you do not want to participate or read, this review is for more. Now I see much more understanding by the group writes in the thread in a constructive and educational sense. Granted that I do not want to read or try to understand and continue to work as they pleasure, they are certainly in their rights.
this is a diy'ers forum, many here build amps and then go to the next one...
so i wonder for what prupose poppilin would like to argue "theories" ad infinitum....
i still can build amps even if i have no idea about.....
even if he's right, there are no awards to be granted, not even a lollipop....
It is not like crazy winding transformers or build blindly capacitors
. Here people can learn the molecular and physical essence of what we see then reflected in the quality of sound. If you do not want to participate or read, this review is for more. Now I see much more understanding by the group writes in the thread in a constructive and educational sense. Granted that I do not want to read or try to understand and continue to work as they pleasure, they are certainly in their rights.
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This is a bit stretched from a general point of view. In a super-paramagnetic material, that is made of ferromagnetic nano-particles, magnetic anisotropy is still there as nano-particles' magnetic moments do have preferred directions. The difference to a conventional ferromagnet is that coercivity is basically removed by thermal fluctuations.
Anyway I think you are right about dielectric hysteresis loss in capacitors but this might be somewhat relevant only in electrolytic and ceramic capacitors (i.e. those materials with high dielectric constant). In the best audio types, like teflon, polypropylene, paper and polyester it is quite small and in a well sorted circuit, especially a preamplifier, other things represent the bottle neck.
The ECC82 is the main bottle neck in your preamp circuit, IMHO. Curiously the ECC82 SRPP was the first preamp I have ever made and I still have it in its ugly box, looking like old amps from the fifties. I might take a picture...
It was good but not great for me. I found that distortion was not improved that much in comparison to the same valve used in a well sorted pure single ended. The mu-follower and the SE + cathode follower are a lot better.
Hi 45
Good to see you around here !
Totally agree !
Because super-paramagnetic materials "by definition" are isotropic, but in the real world, isotropy cannot be perfect and as a consequence appear a little bit of coercivity/hysteresis.
Maybe it is difficult to believe, but I swear that just before to see your post I was struggling with Landau-Lifshitz "Electrodynamics of Continuous Media" trying to understand the thermodynamical issue, amazing ! Seriously !
Totally agree !
The theoretical limit that I was talking about is not the same for all type of capacitors, and most critic are those which coupling output valves, because has a bigger voltage across them.
Seems that you are the only who could understand it.
Agree, but the ECC82 is a bit underrated, off course there are better, but my experience was quite good, maybe because I use all linear regulated PSUs, even for heaters.
The only pictures that I have, taken by my cousin in customer's house unfortunately doesn't show the preamp inside.
I instead, had a bad experience with cathode followers, and my explanation will make laugh everyone, so no comments, at least not today.
Good to see you around here !
Totally agree !
Because super-paramagnetic materials "by definition" are isotropic, but in the real world, isotropy cannot be perfect and as a consequence appear a little bit of coercivity/hysteresis.
Maybe it is difficult to believe, but I swear that just before to see your post I was struggling with Landau-Lifshitz "Electrodynamics of Continuous Media" trying to understand the thermodynamical issue, amazing ! Seriously !
Totally agree !
The theoretical limit that I was talking about is not the same for all type of capacitors, and most critic are those which coupling output valves, because has a bigger voltage across them.
Seems that you are the only who could understand it.
Agree, but the ECC82 is a bit underrated, off course there are better, but my experience was quite good, maybe because I use all linear regulated PSUs, even for heaters.
The only pictures that I have, taken by my cousin in customer's house unfortunately doesn't show the preamp inside.
I instead, had a bad experience with cathode followers, and my explanation will make laugh everyone, so no comments, at least not today.
It is not like crazy winding transformers or build blindly capacitors
the difference in my case is i do not go around telling people that what i did was the right thing to do.....my post is about something i actually built, if people like them or hate them, i do not care....
it this forums there are builders, folks who actually built something and then there are talkers, people telling other people what to do, what to think and yet themselves have nothing to show in terms of something they actually built....
Two reasons
1) Improve the performance of my amps/preamps.
2) Equations are my vice.
have you built the amp you wanted to improve or still busy writing equations?
An externally hosted image should be here but it was not working when we last tested it.
Output impedance 3K ohm.
There's a small discrepancy in Vak from tube to tube (3.4%).
What would be the effect on distortion?
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And there are the others than all the time are showing their products to the groups. Who can show the sound the components , is the sound the goal in this forum?
Who know how sound the devices?
Anyway, in your deepest part of your mind you would like to know such knowledge that support to each wind of your transformers. The other point of view, your feel superior to others because you are a prolific builder?
Or you consider to be more practical is better that be more theoretical? Camon sir, I said clearly that if you don't want to read or share determinate topic your are free in look some different place proportional to the degree of complexity that your mind requires. Every body is free
However if you want to stay here, be like me, like pupil.
, is the sound the goal in this forum?Who know how sound the devices?
Anyway, in your deepest part of your mind you would like to know such knowledge that support to each wind of your transformers. The other point of view, your feel superior to others because you are a prolific builder?
Or you consider to be more practical is better that be more theoretical? Camon sir, I said clearly that if you don't want to read or share determinate topic your are free in look some different place proportional to the degree of complexity that your mind requires. Every body is free
However if you want to stay here, be like me, like pupil.
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The working voltage might be an issue precisely with electrolytic and ceramic types where the effect has some importance.
Film capacitors can be actually run up to the specified max value without problems (they are usually tested for rather long life at 1.3-1.5 times the rated voltage) and the best ones are also truly self-healing. Luckily enough, film capacitors are also easy to make for high voltages because of the good/right properties of those dielectrics. In fact I have never seen polypropylene capacitors with less 100V Vdc rating.
The limitation of these types is rather the capacitance/volume ratio because of their rather low dielectric constant. So they become bulky for higher capacitance values but anyway the difference in losses between small values and bigger ones is quite small and orders of magnitude better than electrolytic and ceramic types.
It's about linearity. My preamp had nice regulated PSU as well and actually was and still is dead quiet. As usual one can read extreme "opinions" about this valve which are not true but if you, for example, replace it with a decent quality 6CG7 you will see a difference being the latter more linear.
I instead, had a bad experience with cathode followers, and my explanation will make laugh everyone, so no comments, at least not today.
I have been reading bad things about CF for ages and all the times I saw the real thing it was because of the bad implementation.
Anyway keeping more or less the same layout you can try with the mu-follower. With this circuit you can really optimize the load for minimal distortion quite easily and such a value will be a very reasonable one. I haven't done it with the ECC82 but I remember that it was around 15-18K with ECC88 and around 30-47K with ECC83, depending on the operative conditions and the actual devices. The only thing you need is a good board that allows you to measure distortion. It's not so expensive in the end and will make you save quite some money on the long term.
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