John Curl's Blowtorch preamplifier part III

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Pun intended, right? Of course the moderation will let it go, it's from a "like" thinker.

Not this time a simple statement of fact, if you find a violation of forum rules in my statement you got me.

Did any of you unlike thinkers bother to notice how bad that THD graph on the recent Parasound amp made John's work look? I spent my own time to check it out and give him a heads up.
 
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Jn
Ps. I'm now spending my time teaching the motion control software guys reality. They were taught basic software coding and tuning, but they have no clue what closed loop feedback systems do, never heard of bode, assume motors are linear, cannot comprehend involute gearing, the list is so very long..

Well I know who to ask when I get stuck trying to work out if the sony biotracer active tonearms were a good idea or a crock. Currently I am in crock mode...
 
So if I'm to translate, either deal with technical things accepted by you, or get bullied by moderation. Do you honestly read the things you post and think that this is fair and okay? My inbox is full of threats. And apparently I've been reported dozens of times and under constant watch. A small number of people are turning this forum into some sort of all think alike cult. It will get real boring real fast around here.
First and foremost. Forward threats to moderation, that is unacceptable.

With respect to technical content, if you present anything I feel is worth responding to, I certainly will. I note you asked about niobium titanium superconductor availability, but when I responded you remained silent.

That is what I've worked with for the last 25 years, so I actually "might" be able to cobble up a reasonable answer to any question you might have regarding use. So I was quite surprised by your lack of response.

Jn
 
First and foremost. Forward threats to moderation, that is unacceptable.

With respect to technical content, if you present anything I feel is worth responding to, I certainly will. I note you asked about niobium titanium superconductor availability, but when I responded you remained silent.

That is what I've worked with for the last 25 years, so I actually "might" be able to cobble up a reasonable answer to any question you might have regarding use. So I was quite surprised by your lack of response.

Jn

I saw your answer. Thank you. But there were 10 others telling me to google. Kind of hard to keep interest at that point.
 
The detailed complications are ALWAYS necessary!!! 😕😕

I generally agree that the real world is lot more complicated than the simplified models we often take for granted. There may be an argument to the effect that most or many things are linear enough to make the approximations reasonable. Depends on the task at hand I suppose. However, people do come out of school full of linear theory. There is a lot of it to learn, and nonlinear stuff often isn't of so much theoretical interest, at least is can seem that way.

Still people have to start somewhere and linear theory seems reasonable for that. If people can't deal with it, then how will they understand more complicated things?

Maybe worth adding that after thinking about how stuff works for a long time, it can be easy to forget what it may have been like at an earlier time in life before we understood much about how anything works. Nevertheless, if like most people we may have felt quite confident at some point we knew quite well how the world works and were already smarter than our parents.
 
Not this time a simple statement of fact, if you find a violation of forum rules in my statement you got me.

Did any of you unlike thinkers bother to notice how bad that THD graph on the recent Parasound amp made John's work look? I spent my own time to check it out and give him a heads up.

Yes, I saw that. I hope he can get it squared away with them. Not sure what else we can comment on it.
 
I saw your answer. Thank you. But there were 10 others telling me to google. Kind of hard to keep interest at that point.

Well, I am not one of the ten others. I work with the stuff daily, building beyond SOTA hardware all the time. If you have a question, just ask. Simple.

I did point out that above cryogenic temps, NbTi is just a poor conductor with absolutely no fancy properties...as I recall, the bybee was referred to as " near superconducting".. Don't recall if it was a mag article, press, or ad copy. But, the guys I work with had some really interesting words about that, none very polite.

I can see why bybee hype is received with "reservations".. But I don't worry about that, I've clarified my position re that long time ago..

Dead horse to me.

However, I always want alternative viewpoints for discussion.

Jn
 
Regarding programmers and motion control, its not something they are taught. People who assign the engineering work at some higher level, or maybe who divide up big projects among the silos don't often don't understand about that.
Actually, there are degrees in that stuff now.
Unfortunately, it still comes up short. They keep asking me to fix stuff, and I'm getting ready to do that "R" thing.

We have almost 3000 widgets (so far) under computerized motion control, with many more on the way. The company that builds the motion platforms teaches these kid horribly (well I'm exaggerating). Unfortunately, they are taught basic how to, such that perhaps 80 percent of the apps can be done with a reasonable success.

I'm called for the last 20%. In particular, I have to fix all the non linear devices, the kids are taught linear only.

But, I continue to scream at the top of my lung.....you cannot fix bad hardware with software. Figure out the basics first!!!

Kinda like eq'ing a poor speaker.

Jn

That R thing.. A friend asked me when I was going to retire...
I said, I'm actually enjoying my work, it is stimulating and fun.
He said...what, you want to die here???
My response...

You haven't seen me give a presentation, have you..
 
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