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Old 8th February 2003, 12:39 AM   #1
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Default Zero feedback amp

Recently I have listened to one of the Densen amp. Company says there is no feedback in their amp. It was really interesting. Did anybody try something like that ?
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Old 8th February 2003, 02:26 AM   #2
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Default Re: Zero feedback amp

Quote:
Originally posted by thomashek
Recently I have listened to one of the Densen amp. Company says there is no feedback in their amp. It was really interesting. Did anybody try something like that ?
You can not build an amp with some gain,
with Zero Feedback without getting considerable distortion.

When you see Zero Feedback mentioned, it means
Zero Global Feedback.
That is No feedback from Output to Input.

They still use local feedback,
either active, or passive with a lot of resistance.

If every stage has enough local feeback
you can get a good amp
with Zero Global Feedback

/halo - has not yet built an amp without some kind of feedback
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Old 8th February 2003, 04:53 AM   #3
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Default Re: Zero feedback amp

Quote:
Originally posted by thomashek
Recently I have listened to one of the Densen amp. Company says there is no feedback in their amp. It was really interesting. Did anybody try something like that ?
I'd be willing to bet, if given a schematic you could find feedback. There are many ways of building negative feedback into a circuit, without the need for global feedback. (Actually, I' think that it's near impossible to build an amplifier without any feedback.)
Feedback reduces distortion.

I happen to like the sound of a low distortion amplifier, and cringe at the sound of a distorted one. However, others may like certian types of distortion. I guess it's all a matter of taste.

If you can come up with a schematic, post it here. I'd be interested in seeing a "no feedback" amplifer scheme.

-Dan
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Old 8th February 2003, 05:56 AM   #4
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Hi

1 of my friends is working at Densen in Esbjerg-denmark but he can't with schematics! But he says that the amp is something like LC-Audios "The Millennium XP" amp.

http://www.lcaudio.dk/temil.htm - sorry no page in english
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Old 8th February 2003, 09:02 AM   #5
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Quote:
Originally posted by DannyCool
Hi

1 of my friends is working at Densen in Esbjerg-denmark but he can't with schematics!
Soooo, the poor slob who has to work on it just...what? Throws the thing in the wastebasket?

Actually silly not to release schematics...anyone who really wants to can recreate it if they want to crack it open. And if they are doing it because they are trying to fix it, I can guarantee he won't be recommending his buddies buy one.

And where did this idea that feedback, global or local, was an evil thing? Say it with me kids: Feedback good, distortion bad. And if someone says something about TIM, I'll wash yer mouth out with soap.
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Old 9th February 2003, 02:04 AM   #6
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Personally, I hope that all amp manufacturers adopt the
same attitude. I understand that Krell international
distributors still can't get schematics. (but of course I
can). MuuuuHahahahaha......

More to the point of the thread: I think that we can all
understand the marketing pressure to say something like
"no feedback", which is the audio equivalent of having
Cameron Diaz in your movie.

Also personally, I accept a certain amount of puffery in
advertising, and allow that "no global loop" qualifies
as "no feedback".
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Old 9th February 2003, 09:18 AM   #7
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Quote:
Originally posted by EchoWars
And where did this idea that feedback, global or local, was an evil thing? Say it with me kids: Feedback good, distortion bad.
Feedback by itself is good! It is PHASE SHIFT that turns Dr. Jekyll feedback into Mr Hyde...
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Old 9th February 2003, 09:40 AM   #8
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Quote:
Originally posted by DannyCool
Hi

1 of my friends is working at Densen in Esbjerg-denmark but he can't with schematics! But he says that the amp is something like LC-Audios "The Millennium XP" amp.

http://www.lcaudio.dk/temil.htm - sorry no page in english
Correct, there are pages in english! Click at the button "English language" up in the right corner or simply surf to http://www.lcaudio.com but not every pages are in english yet, just wait and see, I suppose.
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Old 9th February 2003, 08:10 PM   #9
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Nothing like a nice 4 stage darlington output circuit
to enhance stability.

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Old 9th February 2003, 08:21 PM   #10
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I am just sitting and listning to my brothers millenium amp right now it sounds fine!
What would Krell do if a person published the diagrams?
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