Musings on amp design... a thread split

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The problem with trolls is that engaging with them rapidly transforms into a "whack a mole" game. Trolls love the attention, more so if participants get angry / frustrated. From that perspective P might be back whatever the cost for him. While practicing "patience for the benefit of doubt" is a constructive attitude in science / engineering, THE mark of a troll is to repeat ad nauseum what angers / frustrates members. Issues like "1st cycle distortion" should never have resulted in more than one response.
 
Guys, I personally know the user under the nickname Alnikst and this is not petr_2009. I truly know this because I know both of them personally. I do not know who is under the nickname NikLik, I do not have genuine information.
I understand that the subject matter intersects with them, but this is because Alnikst modeled a couple of versions of the schemes from petr_2009 and this topic was interesting to him. To consider him a clone is a mistake.
 
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Guys, I personally know the user under the nickname Alnikst and this is not petr_2009.

I don’t know but moderators do not take anyone’s words for granted, but check if same person is using different member accounts with other methods that leave no doubt. I know how, but don’t want to educate other trolls.
Anyway, result of the ‘Duck test’ is a very strong indication and Alnikst passed this test as a duck, err. as a petr_2009.
 
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Most people are unable to control their emotions on a level that would prevent trolling or "patriotic" activity etc. The present "situation in the world" isn't exactly one that stimulates cooperation / research in what should be "urgent issues". Maybe a system of "educational" public warnings by moderators could improve things, in the sense of "3 times and you're out". It's more work though.
 
Progress...

Transient analysis of my amp with 10Vpp output in 8 ohms is red graph, the sine source alone is blue.
Nearly identical, my amp just has a tiny bit worse K2.

identical.jpg
 
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Bernhard, that looks very good. The difference with the 1k plot suggests an opamp and in the case of discrete semiconductors, compensation that doesn't include the output stage.
Indeed interesting what the difference between sim and measurement will be. In some cases with tube amps I ran just the FFT in a transient analysis and the results were in agreement with the direct THD sim. BTW to get identical results for "periodic steady state" and "unticked", often 500 cycles are needed at 1k.
 
Not know what you mean by simpler model.
Your own words in #1295.
I built a bit simplified circuit because at the time the schematic was just like that, less refined.
Never used LT spice but the Microcap simulation resulted in a working amp...
Yes I can see you are using Microcap, that’s why I was curious to see how this compares to a real life measurement.
Simulations showing less than -140dB distortion are IMO too nice to be true.

Hans