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Old 27th January 2013, 12:53 AM   #11
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Added with a simple DC servo module and the midpoint voltage adjustment module.
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Old 27th January 2013, 07:50 AM   #12
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Quote:
Originally Posted by thinkhlin View Post
hi Boscoe!
No feedback to achieve low distortion, the closed-loop distortion I believe will be lower.
Are you sure about that way of thinking? It may be a common way of expressing what you really want to say but it's totally the reverse in correctly
designed amplifiers. The basic reason for feedback is to reduce the distortion. The 'closed loop' actually refers to completing, or closing the feedback path.
Negative feedback - Wikipedia, the free encyclopedia

Perhaps though, you are not talking about harmonic distortion but some other quality of amplified sound?
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Old 27th January 2013, 04:19 PM   #13
DF96 is offline DF96  England
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"No feedback" does not achieve low distortion, it requires low (open-loop) distortion.

In practice, most amps have (and need) lots of feedback, but feedback fearers just have to have lots of local feedback to compensate for the lack of global feedback. Alternatively they have to get used to hearing lots of distortion.
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Old 27th January 2013, 05:38 PM   #14
wahab is offline wahab  Algeria
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I guess that he said that he wanted low distorsion with no feedback
and that distorsion will be reduced once feedback is added.

Look like the misunderstanding is due to litteral translation.

Last edited by wahab; 27th January 2013 at 05:45 PM.
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Old 27th January 2013, 07:08 PM   #15
DF96 is offline DF96  England
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Maybe.
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Old 27th January 2013, 10:49 PM   #16
nattawa is online now nattawa  Canada
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instead of throwing your writings in Chinese at google translate and post whatever came out of it to the forum making such a nonsense mess, a better way of using google translate is probably to get it to translate its output back to Chinese and see how much error there is, then try to make adjustment and improvement in wordings, terms, grammar, phrasing, and so on, until satisfaction, prior to posting to the forum.

This is in fact a classic example of how a system without global negative feedback fails.
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Old 4th February 2013, 12:38 AM   #17
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Hi! everyone.
I am not familiar with the use of in English.
In Chinese, The circuit is no global feedback.
This is what I want to say.
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Old 4th February 2013, 08:41 AM   #18
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Quote:
Originally Posted by DF96 View Post
"No feedback" does not achieve low distortion, it requires low (open-loop) distortion.

In practice, most amps have (and need) lots of feedback, but feedback fearers just have to have lots of local feedback to compensate for the lack of global feedback. Alternatively they have to get used to hearing lots of distortion.
Let's add why we actually need feedback afterall.
Global or local feedback is needed to achieve a reasonable bandwith.
ZeroFeedback amplifiers will clearly have low dynamig intermodulation, but a very poos bandwith.
The world of HiFi is full of compromises all the way.
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