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I had already classified you as the anti Science, 100% subjective opinion , "mine is the only Truth" type guy but I never expected this series of confessions to be so clearly stated.
Thanks for the sincerity.
@ginetto61 : What you have to keep in mind here, when you compare your first prototype to this simulation, is that it uses an ideal voltage source as power supply and also an ideal current sink. The load is idealized as well and there are no parasitics included. Going from here to your original question: you need to figure out what to optimize for and take care of that. For example when you build your power supply don't just calculate for ripple suppression but amongst other things also filter Q and make sure the Q of the last decoupling stage is 0.7 (critically damped).
Are we talking 50/60 Hz mains transformers?
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Without previously knowing they are there?
Without seeing them or the equipment presumably housing them?
Wow!
Any Scientific study showing health problems in Humans caused by very low EMF levels created by Mains frequency low power (say less than 1 kW) transformers a few meters away?
Hey, doubt even pacemakers are affected that way.
And those are electrical devices.
A Human using his bare senses?
I respectfully disagree.
EVERYBODY will eventually get one of those, unless some other illness takes them away first, it's a Law of Life.
Assigning that to very weak undetectable fields received many years before is pure imagination/prejudice unless proven otherwise.
Unfortunately, I am not allowed to continue writing about EMF in this forum. But I think learning to do your own research is part of University education;-)
But a very big problem of science is: have I investigated what I claim to have investigated;-)
thanks again very interesting But i see this as quite difficult for me to do
It is all smd these days in dacs I will pass on this mod even if i have no doubt about it
I am very interested in simple buffers to be placed after a stepped attenuator Just that as line control
Very very interesting and easier to do Parts selection aside But there are various reports on resistors quality and sound Thanks a lot
I see I have a question Is it possible that a circuit in real conditions will outperform the same circuit in ideal conditions i.e. in simulation ?
After getting usable settings just out of curiosity i simulated some preamp circuits of which i read good things They were not particularly great at sim
Good but not excellent I was quite surprised because considering as you say that in simulation there are some ideal conditions i would have expected better performance To be fair i did not use the exact transistors but similar I have also learned that topology seems more important than the actual bjts used
If the topology is wrong no bjt can make it work If the topology is right even common parts could provide interesing results
I know its trivial
i am afraid this is too complicated But i need only very small power and voltages Power amps are completely beyond my dreams
I am trying to understand something about unity gain buffers that are already very very difficult in some cases
My main goal is an active volume control I tried passives only and did not like them at all I like some more punch and low end
A really great unity gain buffer following a stepped attenuator and i will be done
That is all i really need A kind of control unit lets say
Thanks again I am doing a infantile thing ... i am looking at the simplified schematic of some op amps trying to mimic their output buffer stages topology
I know that the great performance comes from all the stages together and after application of global feedback but this is what i have obtained just for fun
strangely some circuits proposed as game ending i have not been able to sim And some others already simulated i cant check for lack of models
But i am sure that the default models in LTSpice are already way much more than what a basic user could ever need
The problem with models is that they are models. They are simplified "models" that will show most of the predictable behavior of the real thing. They won't predict what will happen at the parts per million level. They help a lot in predicting voltages and currents. They will not reliably predict the -120 dB distortion of real world parts in real circuits. Thats a different problem best addressed with real implementations (and at some point no longer the most important thing to pursue).
The main thing is that you have it in your head. The practical experience will come - the interest you show also shows that you will get further than the majority;-)
Because just physics: everything and everyone takes the path of least resistance
The word "outperform" on it's own doesn't mean anything. Which factors of the device made it so people spoke well of it? In what context? Can that be attached to measured aspects? Which ones are these? And what is their measured value to be in order to make people speak well of the device?
Hi i see your points Yes i tend to trust too much the simulation However for me it is already a big step ahead really let me explain why
I was following another thread about a minimalist buffer circuit and a member shows what he says is an innovative circuit saying that it took like 50 years for the basic circuit to finally be improved
One expert comments that simply by looking at the circuit you can see that it cannot possibly work
I try to simulate it and it actually doesn't work
Well, being ignorant, I wouldn't have immediately understood how the expert did it, which absolutely couldn't have worked
For example, I look at a current mirror and I don't understand how it can be used inside a buffer.
I'm at these low levels
An educated person looking at a schematic like the one below understands immediately the functions of the various part of the circuit
I can only spot the output buffer stage
You are right I am a "victim" of audio mags reviews
I have been an avid reader and now i understand how much time i have wasted
I could have spent much better this time trying to educate myself a little more on audio electronics and read some books
Of all the discussions i have followed the ones about modding existing equipment have always been my favourites
I remember a designer taking out parts replacing others and end with a better sound
Fwiu some cheap commercial products have a good potential held back by some cost savings on critical parts
The idea is to upgrade these commercial products targeting these critical weak points with a reasonable cost and elevate their performance in an evident manner
I remember for instance an old thread here in DIYAUDIO about a Marantz integrated amp where the modder mainly added two very big caps bolted on the rear panel
I am sure that mod has been very beneficial Unfortunately i cannot find the relevant thread It was here in DIYAUDIO years ago I was amazed
Most of the mods usually concern power supplies that incidentally are the most expensive part of an amp maybe with case ?
Very nice thank you To test a system i like this kind of music The right recording on a great system could be better than the live experience
The cost of the case certainly is a major cost factor. The power supply is never "just the power supply". The signal part modulates the power from the power supply and this is what you get as an output signal. That is why I wrote earlier that you are using ideal voltage sources in your simulation without even giving them a linear (which it never is in reality...) output impedance. PSUD II is an easy software to have a look at the dynamic behaviour of different power supply topologies (stepped load function) that show how your supply will follow load changes (dynamics).
Concerning psu and its audibility: My experience is that the components are more audible than, for example, voltage or current dips that accompany the signal, load changes. Often a slightly weaker psu is even liked by the ear because it makes the sound "livelier". This is perhaps comparable to organ pumps. Smaller pumps sometimes make the sound of the organ seem "livelier". It just has to swing