john curl said:
No please don't misquote me, I agree with Pease DA can be modeled almost completely with a bunch of RC networks completely linear and time invariant. There is no DA distortion.
jlsem said:
Sorry John I don't mean to be a PITA but I'm interested in the specific performances like Reiner and the CSO as you say aesthetics is everything. Please don't take any offense at my comments.
PMA said:
Generator source impedance? Source series resistor value/type? Wiring from source to the DUT?
Man, you really need to read up on the scientific method. If you're serious that is.
Jan Didden
This is not any scientific forum and I have not enough time for DIY only. The generator output impedance was more than 100x higher than that of the resistor measured.
I do not need to read about scientific method, as I have enough of scientific publications.
You are a kind of a nit-picker.
I do not need to read about scientific method, as I have enough of scientific publications.
You are a kind of a nit-picker.
PMA said:
PMA,
Anybody can post a curve and say this is such-and-such. Without knowing how, what etc, it doesn't say anything. It is good practise to include your measurement setup etc so that others can judge your results, can reproduce them if they want, and ask for clarification which can also benefit you.
In that sense yes I am nit-picker.
Jan Didden
PMA said:
Sorry PMA but janneman is right to ask for the details, otherwise we have the potential to end up down a blind alley because we have built our knowledge base on uncertain foundations. Especially so when we are dealing with one of the lowest level and most basic, but fundamental elements of a circuit, the humble resistor.
Hopefully someone who has the equipment and the time can do the experiments fror us and publish the detailed setup and results.
Alan
PMA, I agree with you. You are not putting out 'idle speculation'. You are presenting 'informed measurements'. You are an engineer, you have the test equipment and you measured an OBVIOUS difference between two resistors. DUH! Because that is exactly what we should expect, and this has been known since the beginning of electric measurement.
This is why Ayrton and Perry made their attempt to produce wirewound resistors will low inductance 120 years ago, and Tesla did his about 100 years ago.
EVEN with these exotic windings, there still could be some measurable overshoot with low impedances because the Q of the windings is so high, due to the large wire or its equivalent used.
Why do others 'nitpick' unless they have something directly contradicting to contribute? Then we have a chance to 'nitpick' their efforts as well. It is because the 'facts' are not the issue, with questions like these, but subtle ridicule is.
This is why Ayrton and Perry made their attempt to produce wirewound resistors will low inductance 120 years ago, and Tesla did his about 100 years ago.
EVEN with these exotic windings, there still could be some measurable overshoot with low impedances because the Q of the windings is so high, due to the large wire or its equivalent used.
Why do others 'nitpick' unless they have something directly contradicting to contribute? Then we have a chance to 'nitpick' their efforts as well. It is because the 'facts' are not the issue, with questions like these, but subtle ridicule is.
Otoh, if the differences shown are due to some aspect of the test methodology, the conclusions drawn may be incorrect.
What was shown is sufficient to show that under some uniform test condition that the results from two different construction (and slightly different value) resistors was different. It is reasonable to then logically extend that to say that in some instances one may get different performance in an actual circuit from two different construction resistors.
We can not determine which construction is "better" nor what the true nature of the difference is from PMA's post...
_-_-bear
What was shown is sufficient to show that under some uniform test condition that the results from two different construction (and slightly different value) resistors was different. It is reasonable to then logically extend that to say that in some instances one may get different performance in an actual circuit from two different construction resistors.
We can not determine which construction is "better" nor what the true nature of the difference is from PMA's post...
_-_-bear
bear said:
It was definitely not. I have no axe to grind with anybody. But what was shown was just a graph with some labels. If anybody expects to be taken serious on that account just because 'we're engineers' (whatever that means), he's not an engineer in my book. He's a tinkerer. Which is OK, but we should know.
Jan Didden
jlsem said:
Thanks for that for sure. I had no idea, I remember the folks a Chesky barely keeping going because the audiophiles at the time were so fussy about returning at every little pop and tick.
john curl said:
I forgot to mention that I have Sennheiser HD-600 head phones and a pure class A driver for them. Isn't that OK for hearing small things? Frankly they are too revealing and I find something wrong with just about everything through them.
janneman said:
Nice attack mode, Jan-da-mon...
the fact is that assuming he is not confabulating or faking the results, he did two identical tests where the variable was only the DUT. The rest is self-evident, as I noted.
And have you checked PMA's credentials?
...next case...
_-_-bear
scott wurcer said:
How very interesting!
"...too revealing and I find something wrong with just about everything through them..."
Perhaps this is your big opportunity to try some <gasp> different interconnects going to that headphone amp? Different sources? <gasp>
How about getting some good headphones like some top of the line STAX ESLs?
Imagine how "bad" everything would sound then??
_-_-bear
😀
Thanks bear; I certainly would not post a voltage response to an overshooting current step. And, as you mentioned, I expected the plots were self-explanatory.
Bear, I suspect the Sennheisers are pretty good. However, I use STAX, myself for really serious stuff, direct driven by class A tube electronics.
I just talked to Jack Bybee about this discussion, and he understood it well. I even mentioned that some put his name here 'in insult' on occasion.
I also mentioned to him about something on the internet called 'SCIENCE FRICTION' a British history of scientific argument and resistance to change. Maxwell's equations were mentioned first and foremost.
What Jack had first contacted me was about the 'Naked Singularity' article in the Feb 'Scientific American' (and you think that we have far out ideas)
I just talked to Jack Bybee about this discussion, and he understood it well. I even mentioned that some put his name here 'in insult' on occasion.
I also mentioned to him about something on the internet called 'SCIENCE FRICTION' a British history of scientific argument and resistance to change. Maxwell's equations were mentioned first and foremost.
What Jack had first contacted me was about the 'Naked Singularity' article in the Feb 'Scientific American' (and you think that we have far out ideas)
These guys publish some detailed information on resistors, including a thin film power resistor with a quoted inductance of less than 50nH. Their precision wirewound range is quoted as 3-5 uH by comparison.
Out of interest, in their catalogue they mention for several wire wound types that "they can offer low inductance/reactance versions" so the implication is that wirewounds are NOT non-inductive by default and therefore what we choose to use may make a difference.
http://www.riedon.com/us/index.php?option=com_content&task=view&id=16&Itemid=26
Out of interest, in their catalogue they mention for several wire wound types that "they can offer low inductance/reactance versions" so the implication is that wirewounds are NOT non-inductive by default and therefore what we choose to use may make a difference.
http://www.riedon.com/us/index.php?option=com_content&task=view&id=16&Itemid=26
Though it is a little bit off topic, I would like to mention that I do have "some" experience with shunts, their construction and measurements - attached is a squirrel cage shunt of 1mOhm, 1MHz BW (with compensation), up to 63kA, for short circuit tests of HV and UHV circuit breakers.
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