I don't see how this circuit could produce any cancelation, except if biased in squre law A class.
Could you give some more information?
BR Damir
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Drain is connected to the power supply, regarding feedback same as ground.
Did yu try to simulate, I did and could not get distortion below 2-3 %.
Sorry my mistake, drain is output and no feedback there.
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Exactly so, only the production source is slightly different.
If radio telescopes would be built by the same criteria you preach for audio, then we would probably still believe the sun is the center of the universe.
See what Wayne Stegall has been up to.... maybe a dialog with him might get some more ideas regarding his cancellation techniques? Maybe you can correct or modify what he is showing into something that works for you. maybe you can steer him in our direction.... he seems to like doing the math and SIM a lot.
www.waynestegall.com/audio/distcancel.htm
Thx-RNMarsh
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How do you know the sun is not the center of the universe?
Isn't it all relative?
Just a matter of what model is convenient.
When I do a simple sim on my computer it looks like the sun goes around the earth. Sims are only as good as the input you give them, and in the case of audio it seems that models are still to far from complete to only use them and not our ears or even a microphone to confirm what your sims tell you. As always, garbage in, garbage out.
Same. He states "plausible" FET models. Himmm...
A traditional style bias spreader with 2SK1530/J201 biased to about 200ma does better.
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I think we all know by now that using SIMs to predict measured performance to a reasonable level of usefulness is possible so long as you understand the limitations. As the unity gain frequency goes up the simulations get less accurate at high frequencies because parasitics become more important. But correlating SIMs with listening tests is more difficult - it usually relies on some experience by the individual to match how YOU perceive the sound with a familiar source, known power supply and speakers. I've not had much luck with that myself because I've not done the systematic work needed - others (OS I think ?) have done that and found a much better correlation.
I have WW article abouth squre low cancelation, but I don't think that was good solution as it needs perfect matching devices(dual fet arrays), and it it is biased quite high in to class A, not my piece of cake.
You showed very strange paper saying to get simulated distortion around 0.003%. That is very strange, could you provide whole article? And really what it want to say with 'plausible mosfet models'??
BR Damir
EF2 and 3 are not too bad.
EF3 is .04-.05% thd20, regardless of load. EF2 is the same at 8R ... gets worse with load.
Class A genesis stealth OPS is .001%.
Xover dist. is 95% of the THD. That is why Class A has a "following" and
all those OEM's pursue "non-switching OPS's".
OS
EF3 is .04-.05% thd20, regardless of load. EF2 is the same at 8R ... gets worse with load.
Class A genesis stealth OPS is .001%.
Xover dist. is 95% of the THD. That is why Class A has a "following" and
all those OEM's pursue "non-switching OPS's".
OS
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The exact opposite: Never try, never even try to understand and figure out, strong believes, submission to authority, 'VFA is the only way', 'CFA is not good for audio', never demonstrate, just brutal asset like in your sentence...
That's the exact way you are since the beginning of this thread.
E pur si muove!
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In addition to the non-swtiching is the 'displaced cross-over' and also the heavy biassed AB - both push the cross-over up to higher powers. Then you have to worry about the power level that you are 'measuring' your THD at.
I was fair , 80ma/device - 20k - 8R load (100vp-p)
I did the stealth with the same parameters.
I also have the "HCA" non-switching sim , it does .01% with the same
setup. Too many parts for .03%.😀
OS
yes I do dectct a "strong believes" running through your posts
you are asking us to treat your personal experience as "authority"
which is difficult when you don't mention listening controls, show evidence you can design/evaluate VFA power amps to fairly compare with CFA - your writings, rants seem to point to blind fanboyism in the CFA direction
how can we know that your entire experience can't be summed up as confirmation bias?
thats why I favor solid engineering analysis, objective measures compared against actual close reading of established psychoacoustics, knowledge of signal theory
unfortunately for us EE types that shows that relatively competent design for audio electronics is not a limitation - we need to work on acoustics, loudspeakers, become electroacoustic transducer designers, study rooms, radiation patterns, audio illusions employed by our limited current stereo or simplistic multichannel paradigm to have a real impact on home audio music reproduction
but I will still comment on amp design when the theory is being as badly abused as some here have done
you are asking us to treat your personal experience as "authority"
which is difficult when you don't mention listening controls, show evidence you can design/evaluate VFA power amps to fairly compare with CFA - your writings, rants seem to point to blind fanboyism in the CFA direction
how can we know that your entire experience can't be summed up as confirmation bias?
thats why I favor solid engineering analysis, objective measures compared against actual close reading of established psychoacoustics, knowledge of signal theory
unfortunately for us EE types that shows that relatively competent design for audio electronics is not a limitation - we need to work on acoustics, loudspeakers, become electroacoustic transducer designers, study rooms, radiation patterns, audio illusions employed by our limited current stereo or simplistic multichannel paradigm to have a real impact on home audio music reproduction
but I will still comment on amp design when the theory is being as badly abused as some here have done
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Oh, yes ?
Your bad faith amazes me.
As well as your* way to pontificate against CFA with not the slightest experience of them.
*the handle of naysayers
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