That is because you don't understand how feedback works.gabdx said:
Great engineers only ignored it until it had been invented. After that, great engineers used it and weak engineers sneered at it.
Both have their place.
You have two sensible options:
1. do some reading and thinking, and discover how feedback actually works
2. believe what we tell you
I recommend the first option.
This is an awfully long thread about an issue that has been thoroughly put to bed by Self, Yanniger and Bateman et al.
I also checked electrolytic cap distortion using my QA401. As long as it’s < -3dB is below 2 or 3 Hz, the contribution across the audio band is below the test instrument noise floor.
But, NP’s view on this whole issue is the best ‘. . . So you’re worried about the caps in the signal path? Get over it!’
🙂
I also checked electrolytic cap distortion using my QA401. As long as it’s < -3dB is below 2 or 3 Hz, the contribution across the audio band is below the test instrument noise floor.
But, NP’s view on this whole issue is the best ‘. . . So you’re worried about the caps in the signal path? Get over it!’
🙂
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''So I just kept going.... all the way...to 100% negative feedback, at one point I even removed the DC blocking capacitor. It sounded wonderful"
this is enough for not reading and discrediting the whole paper.
Like the review I was reading yesterday about the YG and the Harbeth40,in which the author praise the cables and the peripheral gears which are a must at this level of sound.
this is enough for not reading and discrediting the whole paper.
Like the review I was reading yesterday about the YG and the Harbeth40,in which the author praise the cables and the peripheral gears which are a must at this level of sound.
Haha, you crack me up! A guy who demonstrated he doesn't understand feedback, discrediting a technical paper on feedback by a single out-of-context sentence.
That gave me a good laugh, thanks!
Jan
read the article about miniature capacitors which have some problems with DC leakage, this is the ONLY problem that I see with 'cheap' pcb feedback capacitors.
I don't think you can hear anything related to a -100db distortion of the cap in the feedback, this is as pointless as discussing cables.
I am grateful for one thing is that I learned that technically non-polar caps are very nice, BUT in practice they sound very bad due to how they are build with a lot more complexity and problems than normal polar cap or film cap.
While you continue discussing high feedback, and 0.001 THD and (bad sounding amps) I continue to ignore this, build amplifiers with parts which have a good sound, build amps which don't amplify through feedback loops the EMF of drivers and use ridiculous control over the woofer for a one note electronic sound.
the proof, I bet he didn't hear anything different (except the placebo effect) with this cap 'upgrade'.
I don't think you can hear anything related to a -100db distortion of the cap in the feedback, this is as pointless as discussing cables.
I am grateful for one thing is that I learned that technically non-polar caps are very nice, BUT in practice they sound very bad due to how they are build with a lot more complexity and problems than normal polar cap or film cap.
While you continue discussing high feedback, and 0.001 THD and (bad sounding amps) I continue to ignore this, build amplifiers with parts which have a good sound, build amps which don't amplify through feedback loops the EMF of drivers and use ridiculous control over the woofer for a one note electronic sound.
the proof, I bet he didn't hear anything different (except the placebo effect) with this cap 'upgrade'.
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Yes, diminishing gains in certain areas is a fact for audio, and distortion numbers going down might be something to doubt on.
But then it would be pointless for you to be here reading all the stuff in this forum, as the idea is to make audio sound better.
If you did not, have a look at Chris Bateman´s tests comparing polar with bipolar capacitors distortion, and how two bipolars in series might be the ideal solution.
https://linearaudio.nl/sites/linear...0 to 100uF caps and 100 Hz measurements_0.pdf
Don´t you think it´s cheap enough to try and listen?
That's disappointing, given all the efforts done to explain the technical issues. I'll try to do better next time.
Jan
If you don't want to believe Bruno, then please read the many articles about Harold Black and his invention of the application of NFB to amplifiers. Or Black's original notes.
As Scott mentions below, if you took that from Bruno's paper as what he thinks, then you didn't read it at all. Bruno does not believe in BS.
What are "miniature capacitors" anyway? I can go to Digikey and look at a million different caps but none of them are just "miniature capacitors". Is it a Class II MLCC, a small Al electrolytic, small Tantalum, etc?
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Bruno's article is very worthwhile but only if you can understand it. I suspect many here diss it or stop reading after the first few lines because its above their head.
That is something that happens in all fields, but the smart thing then is NOT to make strong statement about that stuff you don't have a clue about. This will also help avoiding making a fool of yourself. 😎
Jan
That is something that happens in all fields, but the smart thing then is NOT to make strong statement about that stuff you don't have a clue about. This will also help avoiding making a fool of yourself. 😎
Jan
A question: I remember seeing a post with an opamp-type circuit with two feedback arms, with the blocking cap between the two arms. The nice thing was that the blocking cap could be much smaller in value than usual and still the amp has a low LF roll-off.
I've been trying to find it back, no success. Anybody remember it or posted it? It was not the Maxim app note.
Jan
I've been trying to find it back, no success. Anybody remember it or posted it? It was not the Maxim app note.
Jan
