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Negative feedback Amp=more faithful reproduction?

Negative feedback (NFB) vs zero negative feedback (ZNFB). There seems to be unsubstantiated contention that ZNFB amps sound more realistic. I know this is an age old debate favoring the ZNFB design, but I think most audiophiles have never bothered to look into this matter and believe the advertisements and proponents of zero NFB design. I have been in that camp until recently. My own experience and research into articles on this matter leads to me believe NFB is needed for faithful reproduction of music. I'm not saying NFB design is more "musical", which is a highly subjective term and usually means more euphonic or colored. I've posted a similar question awhile back, but I was hoping we can have a more evidence based discussion on this matter. Perhaps, we need clarification of descriptive terms we use to describe sound. My contention is, in general, NFB designs produces a more accurate or faithful reproduction of music than ZNFB designs. Here is a very good article on feedback and distortion:

http://sound.westhost.com/articles/distortion+fb.htm
dracule1
viridian's avatar
viridian
4,184 posts
 
Just to go on a little further.....

There's no way to know what "faithful reproduction" is, it's just a catch phrase, but, let's for a moment, kid ourselves and pretend that there is. In that event, how could you, as a consumer, isolate the fact that the reason that one component is superior in "faithful reproduction" to another can be ascribed to that one difference in circuit design, the use of NF?
dracule1 OP
1,043 posts
 
Technically faithful reproduction can be measured, no? You compared the input signal to the output signal.
dracule1 OP
1,043 posts
 
Charles1dad and Viridian, did you read the entire article in the link? I think he raises valid points about nature of distortion and feedback in amplifiers. We can't all be complete subjectivists here. Afterall, it's mostly hard science and technology have produced these wonderful high end products we enjoy, with a little bit of snake oil sprinkled in of course :)
viridian's avatar
viridian
4,184 posts
 
"You compared the input signal to the output signal." Just how simplistic is this? So, I'll make it easy, if the two signals are exactly the same but one has 3% second harmonic distortion, and the other has .8% of the, more jarring, 7th harmonic distortion, which is the more "faithful"? Please answer my question.

I did not read the article before, but just now read it, and I agree it is thoughtful and well reasoned, but how he values the subjective result of objective changes is very different than I. And that's fine, as I said before, there are good NF amps and bad. Good feedbackless amps and bad. Unlike the author, I have no fish to fry. And after over 40 years in the hobby, I now find that I am a complete subjectivist. But, as you said, "We can't all be complete subjectivists here." And that's fine with me as well. To each, her own.
clio09
2,978 posts
 
Roger Modjeski has some interesting views on this topic and the application of negative feedback in designs. FWIW I have an amp he designed that uses negative feedback and another that doesn't. I enjoy them both quite a bit.
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