What is wrong with op-amps?

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Note to mods I have an incredibly thick skin I just laugh off most of the comments.

The intent of participation is to have a good time while providing to others and receiving from them knowledge and help.
It is a volunteer involvement and for the people who value their precious time, there is a meaning doing it only as long as the environment is cooperative and productive.

:cop:
Rules are in place and are to be enforced but this is the least desirable action.

George
 
Daniel has provided a good link some posts back. See pages 13- 14 for the answer to your ‘question’ (References 1, 2 on page 29)
http://www.analog.com/media/en/training-seminars/design-handbooks/Op-Amp-Applications/Section6.pdf

Except the 4th time constant was introduced in 1976 by IEC and has nothing to do with RIAA.

That's why I asked what is the exact standard that we're discussing here. While equivocation allows some more or less funny banter, it doesn't lead to any sort of "logic" or "scientific" conclusions.
 
Except the 4th time constant was introduced in 1976 by IEC and has nothing to do with RIAA.
That's why I asked what is the exact standard that we're discussing here. While equivocation allows some more or less funny banter, it doesn't lead to any sort of "logic" or "scientific" conclusions.

I would welcome your catering of logic and science but it comes late and it’s again out of context.

Scott reference to RIAA curve in post #3531 was about the way of implementing the correction in a playback preamplifier, that is C or L as the reactive element.
In addition, his mention to the three (i.e.RIAA cut/playback standard) or four (i.e. RIAA standard plus the IEC’s amendment for playback) time constants and the References 1, 2 in Daniels link are more than enough for the people with good intentions and adequate knowledge to understand exactly what the case was.

You have allowed yourself to be exposed enough here so do not attribute (or project) funny bantering to others.

:cop: Again, you have been warned.

George
 
No, it is different in terms of the purpose, like a sword and a scalpel. Creating new sounds and reproducing sound fields are totally different tasks.
People repeat the same nonsense again and again about added harmonics that increase pleasure, until they have a possibility to dial in distortions practically and hear the difference. Why such urban legend are so live? Because amps with higher distortions on high power often have less of audible distortions, so it is an usual mistake to attribute better sound to wrong, but easily measurable, causes.

Find the YouTube video of Rupert Neve talking about his old consoles, the input strips are still a favorite of many top recording engineers. He says that there sound is due to the transformers. Recording engineers understand that as soon as you put up a mic your using an "effects box".( look at the top recording mics, almost none of them are flat, they change directionality with frequincies, there's proximity effect, etc. ). You move the mic, change its angle, yo adjust the effect. If this wasn't true a studio would only need one kind of mic, a test mic:flat and consistant with angle. So these engineers consider every piece of gear as an effects box because they all effect the sound.
 
What amazes me all the time is why anybody can say that 'feedback does not work' while even a cursory look at the world/nature ('look ahead') shows that 'the world' runs on feedback.

You would have a hard time to find anything happening in the world that is not based on feedback in some way. Processes that show the familiar bandwidth limits, overshoot, settling time and oscillations due to too much phase shift.

I used to point that out and thought the 'other person' would start to think to re-conciliate his views in light of the new information.
And that happens, but in an unexpected way: 'the other person' flatly denies that feedback is happening in the world/nature! Go figure.

That's why we learned in TIASUR so much of differential equations, and why they kept for students ancient analog computers!
 
I certainly think that 'feedback works', but that does not refute that feedback may well have unpleasant side-effects that can sometimes be worse than most of the advantages that feedback gives. We KNOW that negative feedback can cause: added higher order distortion, TIM, and PIM. This can be proven both by mathematics and measurement. It kind of reminds me of the ads on TV for various medicines, where a superficial problem like acne is proven to be reduced, but the medicine has side effects that can sometimes discomfort or even kill you. Was the medicine (feedback in this case) worth the trouble that it might cause?
This is why Charles Hansen and I try so hard to reduce or even eliminate global negative feedback. We find that our designs have a tendency to sound better running open loop, IF we can get the circuit linear enough without adding a feedback loop. Why, I can only guess.
 
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