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 Post subject: C'mon, guys.......
PostPosted: Sat Apr 14, 2007 7:30 pm 
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Benjamin
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How do expect to attract guys like Walt to post here if you don't take the effort to thoroughly read the articles?

Asking questions that you may not understand is one thing, but..........

I know for a fact that Walt worked his butt off on that series. I believe that it is presented in a manner that is accessible for the intended reader to comprehend.

Guess not.

Anyway. I hope that the rest of the series will be made available soon. Word is that there is some really good stuff coming.

Jocko


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PostPosted: Sat Apr 14, 2007 10:25 pm 
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Fred_D wrote:
http://home.versatel.nl/horneman/bmosfet.htm

Quote:
With only a few hundredths of a pF shunt capacitance, it can be done...


Let us know how you do that.

Thank you, Fred, I've been looking around for that graph. As I was saying, the performance results show impedances up in the GOhm range, and 100's of Megs near the top of the audio range. It wasn't me who did this - it was Gary Pimm. Look at his designs if you want to know how he does it. Measured shunt capacitance for his rev5 CCS is 23fF. You may have a critique of his measurement method, and call this result into question. If so, I'd be interested to hear what you have to say, and I won't label you a slanderer if you do.


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Walt's measurement's are fine. Email him with questions and repeat them for yourself before you slam his results.


Fred: Please read my post before you put words in my mouth!

Let me be clear: I am not "slamming" Walt's results. He has indeed illustrated useful differences between circuits. I am critiquing Walt's measurement technique. There's a difference.

We are capable of exchanging constructive criticism here, are we not? Walt is a very talented engineer, as his many exceptional contributions have well demonstrated. He, far more than others of lesser experience and influence, should be able to accept some criticism when his measurement technique is not up to par... and yes, I did read the article, thank you.

With all due respect, the equipment Walt has to work with and the knowledge in his head are easily capable of delivering a much better measurement than was demonstrated. While the measurements were adequate for the lower impedance CCS circuits, a good number of the higher-performance circuits are running into the limits of his test setup's noise floor.

Apologies if I was not specific enough with my comment - I was referring to the 1 Ohm resistor (Rload1) used to sense the current variation through the CCS. 1 Ohm is too low here. 100 or perhaps even 1k would be more appropriate here, and it is quite easy to do a calibration run against a different sense resistor.

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PostPosted: Sat Apr 14, 2007 11:56 pm 
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Benjamin
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Uh.......hate to tell you............

Your criticism of his technique (or whatever) has not been well received in many circles. Perhaps you need to rethink your position.

Jocko


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PostPosted: Sun Apr 15, 2007 2:08 am 
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Cow
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Jocko Homo wrote:
Uh.......hate to tell you............

Your criticism of his technique (or whatever) has not been well received in many circles. Perhaps you need to rethink your position.

Perhaps it hasn't, although I think this has more to do with my words being exaggerated or misinterpreted than it does with what I actually said. I stand by my assertion that 1 Ohm is not sufficient to give the resolution needed to see clearly what's happening at 1MOhm and beyond, and is certainly not enough if one is going to take useful measurements of even higher performance circuits (as I suspect Walt will present), which push past 10M.

It is annoying to me that I made what I thought was merely a passing remark about the choice of sense resistor, and that somehow I'm being vilified for it. Is this how we make progress? I'm not here to cut down Walt - I have no interest in that, and it isn't my nature to do such. But neither do I hesitate to point out what I see as legitimate points of technical criticism. The last thing I expected was to be smoothing ruffled feathers over this. It's not a personal attack, and needn't be received as such.

My apologies to Walt if my comment came off as mildly acerbic. This was not my intention, and in hindsight, I would probably rephrase it. Further apologies if the structure of my initial post made it appear that I was drawing comparison between the performance of Mr. Jung's circuit examples and Mr. Pimm's circuits. This most certainly isn't true, but re-reading my post, I can see how someone might jump to that conclusion. The thought in my head at the time was simply that a 10MOhm limit of measurement (below 1kHz) would not be sufficient to observe the behaviour of very good CCS circuits, to point out that such circuits exist, and that it is possible to measure much higher impedances.

Now can we all get back to the topic of this thread?

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PostPosted: Sun Apr 15, 2007 5:57 pm 
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Benjamin
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Walt. Who will no longer appear here.

I do not see why it is asking too much that people from industry be treated with some respect. It is one thing to ask a reasonable question than it is to question without understanding.

People from industry who do come here only do so to further our learning. They do not benefit in any other way. But all of these forums have a way running people off that I know many would welcome the opportunity to have a discussion with. While I can not single out what goes on here, I am dissappointed. I was hoping for better.

OK, last word on the subject. Back to CCS.

Jocko


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PostPosted: Sun Apr 15, 2007 9:28 pm 
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Jocko Homo wrote:
Walt. Who will no longer appear here.

I do not see why it is asking too much that people from industry be treated with some respect. It is one thing to ask a reasonable question than it is to question without understanding.


Heaven forbid someone not understand everything and ask a question. What would the forum come to if people who didn't know tried to find out? There is simply nothing in this thread that would constitute an attack or disrespect, just a desire to understand. This is how the academic world works -- you write or publish something, and everyone else questions it, and if you can defend it, people might start to believe you. Regardless of your name, you don't get a free pass on ideas.

And this:
Quote:
I don't understand why all this needs to be explained, when anyone could simply read the article(s), and see themselves.

does not constitute a defense. Obviously people didn't get it from the article, so find a better way to explain it to the hoy polloi. I've never seen such thin skins.

Jocko Homo wrote:
People from industry who do come here only do so to further our learning. They do not benefit in any other way.


Flatly untrue. They benefit by increased name recognition and the building of social capital
Ask Nelson Pass.

Quote:
But all of these forums have a way running people off that I know many would welcome the opportunity to have a discussion with. While I can not single out what goes on here, I am dissappointed. I was hoping for better.


Well, this kind of garbage has a way off running the rest of us too. It may not mean much from me as I probably don't have much to offer here, but this is why my visits to this forum are few and far between.

Cheers,

CC


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PostPosted: Sun Apr 15, 2007 10:58 pm 
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Clifton, it is a matter of professional courtesy and respect. I recently spoke to Walt, just last week, and he seemed OK to me. In fact, you people should more fully appreciate the amount of time and effort that goes into an article like that. There is little reward for it, except to have some appreciation from professionals and amateurs alike, who benefit from it. You don't see me writing articles like that, any more, it is just too much work.
To have sophomoric criticism heaped on it (even if it is done unintentionally) is not appropriate.


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PostPosted: Sun Apr 15, 2007 11:33 pm 
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Jocko Homo wrote:
People from industry who do come here only do so to further our learning. They do not benefit in any other way.

It seems to me that just about every time someone new or someone with some level of recognized expertise offers any kind of comment on this forum there is a race to see who can question that author first and most severely. By question, I don't mean asking for clarification or understanding. I do mean something more along the lines of discrediting or even perhaps embarrassing. Maybe it's the relatively anonymous nature of the internet, but I doubt that many people would try the same in person or at some large gathering. Just what is the point of behaving like this? Who is winning what here?

Sorry to go off topic, but this just keeps happening. Magura - please move this where you feel appropriate or even just delete. Thanks.


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PostPosted: Mon Apr 16, 2007 12:54 am 
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How one can attempt to equate someone like Nelson Pass, who has an active business, to someone like Walt, who is retired, is just plain baffling.

Whatever............dude.

Jocko


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PostPosted: Mon Apr 16, 2007 2:02 am 
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Yes, it is a matter of professional courtesy and respect, which goes both ways. Again, my sincere apologies (to Walt especially) if my comment came off as disrespectful. Everyone, from newbie to expert deserves the respect of having their comments considered in fairness, and be given a chance to correct or expand on what they've written.

The amount of disrespect flying around over a pair of relatively well-mannered and relevant (but perhaps poorly worded) posts has blown way out of proportion. And now everyone's upset. Why?

It's a discussion forum, folks - you write something and it's instantly posted. People post when they're tired, hungry, in a hurry, and all sorts of other reasons the words might not come out right. I suspect this has a lot to do with why things sometimes get out of hand. People interpret posts without the benefit of hearing the inflection in a person's voice, and without the face-to-face ability to quickly clarify something which has been misunderstood, etc.

Nobody here has an editor screening their posts to make sure they don't accidentally write something which might be construed as offensive, and we must keep this in mind as we read, too... please don't jump to conclusions based on a sentence or two. More importantly, it would help if we are constructive with one another - asking politely if someone really meant what they posted, rather than assuming the worst and starting a fire with inflammatory comments. Walt was clearly upset when he responded, and I hope that his mood was not influenced by inappropriate offline remarks.

Now we are faced with a sequence of inflammatory posts (from all sides) adding fuel to the fire, and here we are... Walt feels insulted, Jocko's sick of dealing with this $#!+, JC feels like professionals are being disrespected, Clifton feels berated, and I feel like a scapegoat stuck having to defend myself against false accusations. Maybe I haven't got that quite right, but the situation is along those lines.

What a fine mess for a group of people who, I suspect, actually respect one another. :sad:

Let's try and point this discussion in the right direction...

I respect Walt Jung a great deal, and I very much appreciate all of the articles he's published over the years - I've learned a tremendous amount and enjoy the fruit of his efforts. My quibble with his article is a minor one, and not worth wasting all this breath on. My sincere apologies that the discussion has gone in this direction. Likewise, I have a lot of respect for the other forum members and their contributions to the hobby - Fred, John Curl, Clifton, CG, Jocko (I don't envy his job managing this site!), and others. I don't want to see any of these individuals disappear.

If we want to have a more civilized forum, we all need to learn to simmer down and try a more diplomatic approach. A little patience and some respect would go a long way. Can we set this crap aside and give it a shot?

Quote:
OK, last word on the subject. Back to CCS.

Amen to that.

_________________
- Chad.
__________________________

"Fashion is mistaken for good design; moral fashion is mistaken for good." -- Paul Graham


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PostPosted: Mon Apr 16, 2007 3:21 am 
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Don't make yourself the scapegoat. I know that your words came out wrong. If not you, it would have most likely been someone else.

Back to CCS.......ok???????????????

Jocko


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