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John Curl's Blowtorch preamplifier part II
John Curl's Blowtorch preamplifier part II
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Old 28th January 2012, 12:57 PM   #20041
scott wurcer is online now scott wurcer  United States
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John Curl's Blowtorch preamplifier part II
Quote:
Originally Posted by Chris Hornbeck View Post
I still can't convince myself that the source's current output, or even noise, is relevent to the issue of base current injection, unless somehow *all* of the source's current could be injected and become charge carriers.

But the integral carrier injection, that you refer to in your second point, is the part that is (even further) over my head. Is it a fact that charge injection is quantized to one electron size? If so then the effect would seem to fall out naturally, like shot noise, (however small it may be).

Thanks,
Chris
Base current is recombination in the base, it has shot noise plus any excess noise from the recombination process (that's why base current almost always has more 1/f than the voltage noise). Remember the signal is on top of the DC base current which is typically in the uA region 10^13 carriers per second, separating out a noise mechanism for the signal current makes no sense at all. No Maxwell's demons allowed.
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Last edited by scott wurcer; 28th January 2012 at 01:09 PM.
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Old 28th January 2012, 02:08 PM   #20042
Jakob2 is offline Jakob2  Germany
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Originally Posted by SY View Post
Perhaps I'm not nearly as smart as you. I can't figure out which answer is the actual one.
Or, you are trying to be too smart sometimes.

If i write an article or a test report, than it would be a comprehensive description of the test objectives, the methods, the gear used, the data and the statistical analysis and the conclusions drawn.
That takes something around 5-12 pages (sometimes even more) and if i release this report then i consider it as published.

As i did post over the years comments on our tests (or test results) and sometimes did post an incomprehensive description of a test, i do not consider these tests as published, something other users might have read.
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Old 28th January 2012, 02:33 PM   #20043
Jakob2 is offline Jakob2  Germany
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@ jneutron,

thanks for the guidance to the papers, iīve found these at Malcomīs webpage.

BTW, very nice solution with the CVR!

@ ScottWurcer,
Quote:
Originally Posted by scott wurcer View Post
I scored 100% without even listening to the music at an AES demonstration by listening for the A to B and B to A clicks.
Thatīs the reason why a negative control must be included in a test like that.

But to exclude a test result as an outlier, just due to statistical reasoning is very dangerous, when you are trying to find out if "at least someone could detect a difference" .

Wrt to the -100dB of a 2mV amplitude- shouldnīt the number be a bit more around 1.8 * 10^6 electrons per second at max, and of course varying with time while following the waveforim?
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Old 28th January 2012, 02:46 PM   #20044
Jakob2 is offline Jakob2  Germany
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Originally Posted by scott wurcer View Post
Do you think folks will ever stop trying to PROVE digital audio is flawed by using waveforms that violate the sampling theorem?
While one should not use those test signals to prove that digital audio is flawed, it is still very useful to test with artificial one sample impulse (for example) or other violating signals as long as nobody ensures that these waveforms will not occur in music files.
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Old 28th January 2012, 03:09 PM   #20045
PMA is offline PMA  Europe
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John Curl's Blowtorch preamplifier part II
Digital audio (Nyquist frequency limited) is "perfect" only in theory. The real digital audio deals with non-ideal anti-aliasing filters, non-ideal A/D and D/A converters regarding linearity, non-ideal converters regarding several kinds of jitter, non-ideal sampling etc. etc. Digital audio is thus flawed both by principle (frequency limited and resolution limited) and by non-ideal realization of every of its parts.
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Old 28th January 2012, 04:17 PM   #20046
john curl is offline john curl  United States
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There is a good reason why 'classic' analog audio such as the Blowtorch and Vendetta (phono) are still around, used and discussed, even years after the last one was produced.
I keeps people 'honest' about what is audible and what is not. Without SELECTED vinyl records or analog master tapes as an occasional reference, we forget the goal that we are attempting to design towards. We 'wallow' in TV sound, convenient portable players, digital based FM transmission, and even CD's, which while sometimes very good, are seldom perfect. It can be a shock that reminds us of something we have overlooked, like fast food compares to haute cuisine.
Many here are happy with 'fast food' and consider 'better' as a waste of money. And so it goes!
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Old 28th January 2012, 05:10 PM   #20047
brianco is offline brianco  Ireland
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@PMA & @John Curl:

Well said - both of you.
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Old 28th January 2012, 05:11 PM   #20048
Joshua_G is offline Joshua_G  Israel
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Quote:
Originally Posted by hitsware View Post
Maybe Watt delveloped I^2 / R
Or E*I.
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Old 28th January 2012, 05:15 PM   #20049
Joshua_G is offline Joshua_G  Israel
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Originally Posted by PMA View Post
V = RI is true for a model where R is constant
Or when R is linear…
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Old 28th January 2012, 05:18 PM   #20050
Joshua_G is offline Joshua_G  Israel
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Quote:
Originally Posted by brianco View Post
@PMA & @John Curl:

Well said - both of you.
Indeed.
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