And you are allowed to 'think' and the problem is when not being able to discuss what we think, that would be kinda sad.
Re ByBee, no experience with it, but my understanding is this works on the quantum level and here we things are so weird that we can only observe and not explain. Just use it, the Copenhagen Interpretation... which is where I just arrived in a few hours ago.
Re open loop versus feedback. I don't think feedback is bad, but I prefer not to make amplifiers with global feedback. But in tube amp's I will use as much local feedback as I can get away with, well, within reason of course.
I like open-loop tube amps, but here I put a large amount of local Anode feedback back onto the grid, include the coupling cap inside it the local loop, get the Anode impedance into the output tubes halve that of Triode (but the tube is a Pentode) and hear things like I have not heard before. It has been done before, but I have never seen anybody to push the concept, until the late Allen Wright and myself decided to go down that way. Allen used massive amounts of Cathode feedback (Cathode winding), but I went down the Anode feedback track
Maybe some here might find it interesting, because is feedback.
The feedback here is virtually in 'real time' except for the coupling cap, which has to have a large value for LF (ideally longer. time constant than the transformer). The bitch of the circuit is the driver stage, need to swing around four times the voltage of Ultra-Linear stages. Ouch! Anybody here wants to try the above idea, be my guest, they will enjoy the challenge. It works.
Take below as conceptual only. I prefer doing it with 6CA7/EL34 and not KT88/KT120.
I like open-loop tube amps, but here I put a large amount of local Anode feedback back onto the grid, include the coupling cap inside it the local loop, get the Anode impedance into the output tubes halve that of Triode (but the tube is a Pentode) and hear things like I have not heard before. It has been done before, but I have never seen anybody to push the concept, until the late Allen Wright and myself decided to go down that way. Allen used massive amounts of Cathode feedback (Cathode winding), but I went down the Anode feedback track
Maybe some here might find it interesting, because is feedback.
The feedback here is virtually in 'real time' except for the coupling cap, which has to have a large value for LF (ideally longer. time constant than the transformer). The bitch of the circuit is the driver stage, need to swing around four times the voltage of Ultra-Linear stages. Ouch! Anybody here wants to try the above idea, be my guest, they will enjoy the challenge. It works.
Take below as conceptual only. I prefer doing it with 6CA7/EL34 and not KT88/KT120.
An externally hosted image should be here but it was not working when we last tested it.
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I have long suspected that 'shot noise' in a valve used under normal bias conditions is actually thermal noise. I am less clear that shot noise and thermal noise are fundamentally the same thing, as claimed in the article linked by Scott above. The Johnson-Nyquist derivation of thermal noise makes no assumptions about the discrete nature of charge carriers so in a different world where electricity really is a continuous fluid there would still be thermal noise but there could not be shot noise.
The 'new' noise source mentioned by KBK is surely shot noise driven by Seebeck?
So do we have one fundamental white noise source or three? I think I would still vote for two.
The 'new' noise source mentioned by KBK is surely shot noise driven by Seebeck?
So do we have one fundamental white noise source or three? I think I would still vote for two.
For you guys with extraordinary hearing abilities, I have two files, a wire vs. tube with distortion shown in
John Curl's Blowtorch preamplifier part III
The files are at http://pmacura.cz/ella.zip
Can you tell the difference by listening, can you tell which is which (wire, tube) by listening? Are you positive in DBT? I may start a thread on this.
John Curl's Blowtorch preamplifier part III
The files are at http://pmacura.cz/ella.zip
Can you tell the difference by listening, can you tell which is which (wire, tube) by listening? Are you positive in DBT? I may start a thread on this.
One could possibly invoke limiting cases? IIRC the simplest expressions have no frequency limit. Certainly an argument worth having though the physics tn that world would be very different.
Nyquist's original redo of Johnson's formula, at the end it's interesting. I have not gone through Carver Mead's arguments in detail.
https://web.mit.edu/8.13/8.13c/refe...uist-thermal-agitation-of-electric-charge.pdf
Maybe in 'fluid world' the relationship between thermodynamics and statistical mechanics would have to be different, so maybe there would not be kT energy per degree of freedom?
Cooper pairs in a BCS superconductor ought to exhibit higher shot noise than electrons, but how you get them to cross a potential barrier so you can measure the noise is beyond me.
Cooper pairs in a BCS superconductor ought to exhibit higher shot noise than electrons, but how you get them to cross a potential barrier so you can measure the noise is beyond me.
File 2 is fatter and more compressed with some loss in vocal articulation and I can't hear the room as well so that is probably the added tube circuit. You used a mono source that is a tube recording from the get go so that means I had to go through it three times rather than once to get my bearings.
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