looking at various threads for so long time now also producing some baby stuff my shelf ( figers with my theory background 
) here is something that crossed my mind
some of the designers we have here simulated one circuit ...then tweak this and tweak that ... then again add a few of this technology and a few of that technology ( fair enough, i do this my shelf actually ) then through a schematic in the forum that produces a few gozillion watts and astronomical slew rate ,damping factors, bandwidth ....and so on and on ....
I wonder how often these astronomical figures we see is the result of the simulator or the results measured from the real product ..i say real product since this schematics normally come with a pcb
just a simple question
) here is something that crossed my mind some of the designers we have here simulated one circuit ...then tweak this and tweak that ... then again add a few of this technology and a few of that technology ( fair enough, i do this my shelf actually ) then through a schematic in the forum that produces a few gozillion watts and astronomical slew rate ,damping factors, bandwidth ....and so on and on ....
I wonder how often these astronomical figures we see is the result of the simulator or the results measured from the real product ..i say real product since this schematics normally come with a pcb
just a simple question
in return 
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I find using Spice to simulate amplifiers is like a Video game. Seriously. It's a lot of fun at times. The idea of the game is to get the best simulation results, most often defined as lowest harmonic distortion. You can use any topology you like and you are allowed to use a pure resistive load. Level 1 you don't have to worry about psrr or thermal management. Level 2 gets harder because you need to include them and prove stability. Level 3 you have to demonstrate good clipping behaviour. Level 4 you have to use a more complex load. There are variations of the game where the idea is to use the smallest number of parts.
You never have to build it of course.
You never have to build it of course.
looking at various threads for so long time now also producing some baby stuff my shelf ( figers with my theory background
some of the designers we have here simulated one circuit ...then tweak this and tweak that ... then again add a few of this technology and a few of that technology ( fair enough, i do this my shelf actually ) then through a schematic in the forum that produces a few gozillion watts and astronomical slew rate ,damping factors, bandwidth ....and so on and on ....
I wonder how often these astronomical figures we see is the result of the simulator or the results measured from the real product ..i say real product since this schematics normally come with a pcb
just a simple question
The only amp Ive seen here with any kind of astronomical figures is Syn08 and Edmond s amp, and yes its a real design, its built and working. The others are mostly concepts or prototypes with typical figures.
What you should find strange or even funny is how each designer claims his amp to sound the best in the world, this without having compared it to even 3percent of built designs available in the world or claiming that their amp is vastly surperior to any commercial designs available
hmmmm i play the exact same game with pcb design ...one has to be moree symmetric other has to be longer other has to be smaller ...and yes that is a very nice game but the results from pcb to pcb has many variations on how it works and how it plays ...add to this the long term stability and you are done ....
i will never forget a friend of mine that asked me to design a P3A pcb long enough to fit inside some plasma TV speakers ( it was an insane project ...but that was the fun of it ... ) i actually did the pcb ...given also the expirience i have around the P3A ive done it two leyers and done it properly from every aspect ...but the blody thing never played properly and i can tell why ...some ground issue ....some feedback issue ??? who knows ...
that is my point exactly ...one pcb or bad choise of part or part with the wrong tollerance and your astronimical simulation is blown to the moon ...
i belive that we should be more skeptic arround these so called perfect amps happily presented in the forum and start to look to more sophisticated methods of evaluation than a fisrt stage simulation ...
regards sakis
( hello Jan my friend ...are you doing allright ??? happy regards from sunny athens !!!)
the truth
Thank you bigun & all for telling the truth. "It's a big video game" "you may use a resistive load". I've been wondering about this sold state forum. I read something in the seventies that said systems with speakers typically produced double digit percents of distortion, etc. So I wonder what has changed, why the last .1% mattered in the amp. I can understand the numbers game, but as a music hobbiest, I've been spending 5 times as much on the speakers as the amp. Lacking the big bucks to instrument my living room to test sound sytems, I've been using those poor but oh so pleasing substitutes- my ears. I've put 100 times as much money into source media as the sound system.
Thank you bigun & all for telling the truth. "It's a big video game" "you may use a resistive load". I've been wondering about this sold state forum. I read something in the seventies that said systems with speakers typically produced double digit percents of distortion, etc. So I wonder what has changed, why the last .1% mattered in the amp. I can understand the numbers game, but as a music hobbiest, I've been spending 5 times as much on the speakers as the amp. Lacking the big bucks to instrument my living room to test sound sytems, I've been using those poor but oh so pleasing substitutes- my ears. I've put 100 times as much money into source media as the sound system.
Laughed at that one.
The usual course on here for an amp is too start off simple then by the time everyone has had their input it becomes bloated beyond recognition !
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