Seeing a tree is feedback. Experience of hitting something that you see was already learned, thanks to feedback. Just one more hidden loop, like in a triode tube. ;-)
It is not a wah-wah effect, it is a flanger effect. A first, it was made using tapes. Then, digital delay lines (well, bucket brigade delay in the middle).
Del Casher - the first guy to realize the wah-wah is good for guitar. https://www.youtube.com/watch?v=o2m3tWCxc3s
Don't forget all the wha wha contributions of this musician: https://www.google.com/webhp?source...2US664&ion=1&espv=2&ie=UTF-8#q=wah wah watson
That is because there is no fundamental problem. We can't see it because it isn't there. Seeing things which are not there is called hallucination.morinix said:
Few nanoseconds. Completely irrelevant for audio, irritant for HF radio, problem for microwave radio.
No. More myths/hallucinations.
It matters a great deal. Answering "how large" can turn a big problem into an irrelevant problem, or vice versa. That is why scientists and engineers are taught to estimate stuff, so they know what to concentrate their effort on. Answering "how large" tells us we don't have to worry about individual air molecules hitting a vinyl stylus, we don't have to worry about time delays in feedback, but we do have to worry about thermal noise in resistors.
You are actually asking us to put down our brains. Having seen the way this affects other people (it causes them to talk nonsense) I am sure you will not insist on us doing this too.
Still spouting nonsense.
I would be interested to know what you mean by "higher math". To do electronics you need at least arithmetic and very basic algebra. To understand electronics at a fairly superficial level you need more algebra and some basic calculus. To begin to really understand you need things like Fourier series (which come from orthonormal basis sets in a linear vector space) and vector calculus (for electromagnetism). Are you at the 'doing' or 'understanding' level?
As the input is always bandlimited you can guarantee that the 'something' is still present at the input, and will be for a long time.
Oh dear! Do you realise how many trolls you have just fed? You can't make technical jokes with these people because they can't tell myth from reality.benb said:
At last you say something sensible. Yes, there seem to be a lot of people who make their living from audio electronics yet seem unable or unwilling to grasp the basic elements of electronics. Why this is so is a mystery to me, because I have always earned a living from things I understood. Mysterious though it is, I have stumbled upon so many of them that now when someone new pops up talking nonsense with great confidence I automatically wonder if they are in the audio business.morinix said:
This is similar to the way in which whenever I see a really ugly new building I automatically wonder if it has won an architecture prize. Not far from here there is a really bad road junction. It was rebuilt a few years ago to a new design, but if anything is worse than it was before; it too has won a prize for its designers. It seems that these days to really succeed you have to be incompetent but have good PR.
Any network with inductors (especially ferrite-cored inductors) is almost certainly guaranteed to be significantly less ideal in its behaviour than an RC network (active or passive) with the same nominal response. Therefore the preference which some have for LCR RIAA cannot arise from better electrical performance. I suspect either fashion or a preference for response anomalies are the true explanation.Markw4 said:
At best a CC resistor is a fashion statement. At worst it adds noticeable distortion and noise. Some may prefer this.
What amazes me all the time is why anybody can say that 'feedback does not work' while even a cursory look at the world/nature ('look ahead') shows that 'the world' runs on feedback.
You would have a hard time to find anything happening in the world that is not based on feedback in some way. Processes that show the familiar bandwidth limits, overshoot, settling time and oscillations due to too much phase shift.
I used to point that out and thought the 'other person' would start to think to re-conciliate his views in light of the new information.
And that happens, but in an unexpected way: 'the other person' flatly denies that feedback is happening in the world/nature! Go figure.
Jan
You would have a hard time to find anything happening in the world that is not based on feedback in some way. Processes that show the familiar bandwidth limits, overshoot, settling time and oscillations due to too much phase shift.
I used to point that out and thought the 'other person' would start to think to re-conciliate his views in light of the new information.
And that happens, but in an unexpected way: 'the other person' flatly denies that feedback is happening in the world/nature! Go figure.
Jan
Nonsense. Can you clarify the exact action of yours on the tree that this "seeing" is a feedback of? And, in particular, how the bicycle is involved in the process?
The real fun starts when you reach the sophistication level where you understand that, with nonlinear systems with memory, Fourier analysis is as useful as feathers on a horse. Then you will get labeled as "Fourier denier".... 🙄
I suppose if the one with the L in the passive circuit behaves exactly the same and the one with C in the feedback, then they would undoubtedly be exactly the same with both steady state and "other" excitation. Given that an L in a passive network just about never ever acts exactly the same as a C in a feedback network, I feel pretty good.
Only strongly nonlinear systems. For weakly nonlinear systems (i.e. most audio electronics for most of the time) one can use perturbation techniques. I guess some audio systems are so badly designed that Fourier is less use, but that is not an argument for badly designed systems or ignoring Fourier. Anyway, you have to learn about Fourier in order to know when you need something better; almost all Fourier deniers have not even take this first step so their pleas arise from ignorance rather than superior knowledge.Kirchoff said:
Two things cannot behave exactly the same, and behave differently. Ordinary dumb electronics does not know the difference between steady state and "other" excitation; it simply sees a voltage and has some knowledge of the history of that voltage (typically only the very recent past, and an average over a longer period).bear said:
Yes. Under almost all circumstances the L will behave worse than the C, in the sense that it will be less like an ideal L than the real C is like an ideal C.
An RIAA has three (four sometimes) carefully defined time constants with a transfer function that is well known, expressed for instance in the s domain. It doesn't matter how you make it either it's an RIAA or it's not. The amplitude and phase conform the the RIAA or they don't.
You don't even need a simulator you can use pencil and paper and Laplace transforms, I'm sure Waly could walk you through it. Putting stuff together and tinkering until you get a sound you like and hope others will like it too is fine, if you want to call it design go ahead.
EDIT - http://www.sowter.co.uk/pdf/RIAA.pdf They even will make you feel good by saying feedback "alters" the sound while providing no references as usual. But make sure you read the list of problems with it and the statement of why RLC can only approach the accuracy of RC RIAA.
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And tram rails will bring you down, still walking on clutches from a mishap 4 weeks ago 😎
As a matter of fact, the gyroscopic forces at play are minute. The reason you don't fall off your bike are minute corrections made by steering. The front wheel paints a sine wave over the line drawn by your rear wheel. This is classic feedback.
Where would you draw the line as to what should qualify for being called design in general? Please recall that the cosmetic layout of the outside of a product is referred to as design by some. Same for coming with a custom molded plastic box to hold a product perhaps with clever ribs on the inside to hold a circuit board, which may or may not involve a lot of FE analysis, but often does not.
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For non-LTI system characteristics Fourier analysis can be highly useful. Just take energy storage in loudspeaker drivers. These are analyzed with a cumulative spectral decay as a first step, FA slices in time.
If you are not trolling please tell me you just learned something.
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Many years ago, I demonstrated the difference between negative and positive feedback with a bike. The test subject was asked to reverse his hands on the handle bars (left hand to right handle and vice versa). That way, the phase of his feedback corrections was changed 180 deg making it pos feedback. He crashed within a few feet. 🙂
However, if you persevere, you can learn to ride this way relatively quickly; your brain needs very little time to internally reverse phase. Really works, I kid you not.
Jan
Do you even understand the difference between "signal analysis" and "system analysis"?
Or are you just trolling through equivocation?
Ha, another great example of https://en.wikipedia.org/wiki/Equivocation .
How about you first write down here the definition of "feedback", preferably one that applies to op-amp circuits, and we'll take the discussion from there, debating strictly that sense of the word?
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