No SY it has already been covered that we are talking about thermal noise. So do you have any reason why? Now in use where the resistor heats up the answer is obvious.
So why don't you continue your mystic true believer routine.
Or did you not know a resistor makes noise even without any external power.
Would you like to discuss RC noise formulas perhaps RL ones?
Maybe even excess noise issues.
A Rufus then?
Still waiting on the first question.
Or can we stick to friendly intelligent discourse?
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Well actually the Johnson noise formula contains all necessary variables. The claim is intended to violate the second law or in essence Boltzmann's constant isn't.
Any lossy process has noise including DA in a capacitor and all mechanisms contributing to the Q of an inductor.
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Scott,
I think you will get my point. If I have two circuits both powered by +&- 15 volt supplies, one draws 10 mA the other 40 mA, which is the noisier load?
Which requires larger value decoupling capacitors?
OK you need heat!
Just for kicks I did build some of the internet perpetual motion machines. Guess what? None of them worked.
What does that have to do with audio DBT?
You tried to use that as a bogeyman last time and failed. Repeating it won't give you a different result.
Hi Chris,
I fear you misunderstood... I've gone to a well travelled road and my beliefs changed but the other way round the one you suggest...
I come from a scientific background and I believe that the scientfic method is best we have around to explore nature and the universe.
I never abandoned that side and , sincerely, I think that at least some of the hard skeptics abandoned, instead, the real spirit of science making scientific models and engineering best practices as dogmas.
Dogmas, by definition, needs an act of faith and can't be discussed, not a science thing, IMHO.
Every scientific model is, by definition, an aproximation of reality, often an incredible good one but subject to revisions and improvements, otherwise we would be stuck at Newton model...
Some of the partecipants to my Group Buys works as engineers, do research in universities, sometimes even at pinnacle research institutes.
And none of them argued that my sometime silly recommendations were 'scientifically' impossible... sometime they were a bit skeptical but nevertheless tried and enjoied results.
Absolutely, in fact what I do with passives is a selection work, not only by ears, to squeeze the last bits from a good engineered design.
And most of my passive selection work is with plain industrial parts, very few 'audiophile' parts survived the years...
Quite all audiophile resistors are way colored, for example, the most transparent are very good quality industrial parts, most by Vishay Group, by incident...like Dales and VPG.
Jakob - I see you recycling the same argument - but did you effectively reply too:
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A 1k resistor has 4nv/rt-Hz noise on its terminals even with nothing connected to it, that's what I meant. At the 1k level it is not too hard to approach the 0dB noise figure limit.
Ed,
G-wizz, I found a Kistler precision quartz accelerometer in my kit yesterday. It has individual traceable calibration. I measured .0046G rms from 20-20k sitting on my desk, the calibration was easy to check roughly by dropping it freefall for a foot or so and looking for 1G +- (yes of course it was coupled at near DC for this). This was all transducer limited noise since it is a 100G max version, pure 1/f so I assume the reality is much less.
1G vibration is quite a bit of shaking going on, I think the BW on the quoted .05G background is virtually all at very low sub-audio frequencies.
G-wizz, I found a Kistler precision quartz accelerometer in my kit yesterday. It has individual traceable calibration. I measured .0046G rms from 20-20k sitting on my desk, the calibration was easy to check roughly by dropping it freefall for a foot or so and looking for 1G +- (yes of course it was coupled at near DC for this). This was all transducer limited noise since it is a 100G max version, pure 1/f so I assume the reality is much less.
1G vibration is quite a bit of shaking going on, I think the BW on the quoted .05G background is virtually all at very low sub-audio frequencies.
Actually I think I dropped a zero! Went back and looked, I did.
I didn't want to use m or u as I thought that would not be clear. My bad. I had someone correct me on 1/f noise. That he claims is pink noise and what it should be called is shot or Poisson noise.
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Scott
We both know what we mean by 1/f noise and how if falls into the thermal noise. When I mean pink noise I'll call it that.
As to enthusiasm actually been a bit depressed last few weeks!
One of the things I learned in college is that if you set a mechanism to make getting things done to be almost as easy as sitting on your behind, things get done.
The best example of that is in my screwdriver/wrench collections. One for the wood shop, others for my bench, the assembly bench, the metal shop, the office and then everyone also gets their own set. Saves time and effort when the tools are right at hand.
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