No, the addition of higher order harmonics by NFB is a physical fact that can be proved mathematically.
Any feedback, however small, will create re-entrant distortion unless the forward path is distortionless.
The subjective and/or measurable result will be a discussion topic, i.e. if this is an audiophile myth or not, but I don't want introduce more polemic issues, so, if you want, I take that back...Eppur si muove...😀
Last edited:
What I meant, and what I said, was that any higher order harmonics added by feedback would be so far down that you can't hear them. Therefore, they are not important. In my research, and in my circuits, any higher harmonics added are miniscule and so far down that it does not matter at all. The benefits of feedback far outweigh any drawbacks.
I thought overall feedback run out of steam at high frequencies because of the low amplification of a triode. As a result only lower frequencies were corrected, as well as output impedance. Well, I've seen that somewhere long ago 😉
The software I use is Adobe Photoshop, it's commercial. Older versions (for Apple G5 computers for instance) can be had for almost free as these computers are redundant in Holland.
The software I use is Adobe Photoshop, it's commercial. Older versions (for Apple G5 computers for instance) can be had for almost free as these computers are redundant in Holland.
Ah, but Popilin designs his amps based on theory, only. He doesn't allow little things like real life get in the way.😱
Mathematically speaking, there's even the probability this conversation isn't even taking place. That doesn't mean it has any influence on perceived reality.
As you don't know all my designs, this is a bit temerary claim. IMHO
If I were able to design an amplifier without theory, I would be a kind of "paranormal designer" and would be accused as a charlatan.
In the classical limit, GNF does work, and I also use it as a last resource, e.g. in PP amplifiers, mostly due to OPT nonlinearity and FR, does not make sense to me ruin an SRPP with GNF.
It can be said that it is a design criteria, or a theory-based prejudice if you want.
Mind you that I also design and build my own transformers, and, like capacitors, in the real life are not ideal devices.
Paradoxically, realize this, requires a lot of theory. 😉
If you mean Quantum Mechanics, or even Philosophy, seems to me it is off topic, so no comments.
Last edited:
Hi,
There are those who believe that a component (any component) is just what it is supposed to be and will conform to all mathematical models.
Then there are those who know from experience that no component is what it is supposed to be.
Nothing's ever perfect, accumulating imperfection after imperfection is not going to change that, is it?
Never mind, 😉
There are those who believe that a component (any component) is just what it is supposed to be and will conform to all mathematical models.
Then there are those who know from experience that no component is what it is supposed to be.
Nothing's ever perfect, accumulating imperfection after imperfection is not going to change that, is it?
Never mind, 😉
Hi Frank
Good to see you around here ! 🙂
I have nothing against experience, indeed I have quite of it, but, how these people do to know, e.g. that losses are related to linearity, without using theory? 😕
Mind you that I have not the crystal ball, only paper and pencil. 😀
Good to see you around here ! 🙂
I have nothing against experience, indeed I have quite of it, but, how these people do to know, e.g. that losses are related to linearity, without using theory? 😕
Mind you that I have not the crystal ball, only paper and pencil. 😀
indeed, it is the actual working amplifiers that matter more than any mathematical models, we do indeed live in an imperfect world.....😉
it takes more than a paper and pencil to build things.....
i am more concerned about Murphy, ignore him and the magic smoke makes an appearance....
Theory is when you know everything but nothing works.
Practice is when everything works and nobody knows why.
In our laboratory, theory and practice are combined:
Nothing works and nobody knows why.
😀😀
Practice is when everything works and nobody knows why.
In our laboratory, theory and practice are combined:
Nothing works and nobody knows why.
😀😀
Hi,
Theory is your basis. Reality is more often than not different from pure mathematical approach.
Ask yourself: is a resistor just a R?, Is a capacitor just a C? Is a wire not composed of L, C and R?
And so on.
Ask yourself, is whatever you assume is scientifically proven actually true?
Or are these self-proclaimed scientist just feeling comfortable behind what they think is true?
Ciao, 😉
Theory is your basis. Reality is more often than not different from pure mathematical approach.
Ask yourself: is a resistor just a R?, Is a capacitor just a C? Is a wire not composed of L, C and R?
And so on.
Ask yourself, is whatever you assume is scientifically proven actually true?
Or are these self-proclaimed scientist just feeling comfortable behind what they think is true?
Ciao, 😉
Reality is the true, theory is just an approximation.
Can you answer these questions without using theory?
Mind you that I am not a self-proclaimed scientist, I'm just a TV repairman. 😉
Hi,
It may have escaped you but I actually agree with your approach.
The excuse of being just a TV-repair man leaves me with no excuse whatsoever....
Ciao, 😉
It may have escaped you but I actually agree with your approach.
The excuse of being just a TV-repair man leaves me with no excuse whatsoever....
Ciao, 😉
Has the roll off a 3dB slope, starting a decade higher?
That would take circa one-and-a-half dB extra at 32Hz, wouldn't it?
An externally hosted image should be here but it was not working when we last tested it.
Heaters elevated by 100V, two days running.
I must confess that I'm a bit dizzy with your actual circuit, if it is this, your first order high pass filter is determined by the network C1-R5//R6, then -3 dB frequency roll off, with C1=1 µF is
fo = 1 / (2 π R C) ≈ 16 Hz
With C1=4µ7
fo ≈ 3.4 Hz
No, the slope is 6 dB / octave
One octave means a 2:1 ratio
Very nice !
How does it sounds ?
- Status
- Not open for further replies.