No global negative feedback

Discussion in 'Hi-Fi and General Audio' started by melorib, Jul 28, 2007.

  1. melorib

    melorib Lowrider

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    I have done it, resistors and caps removed... :rolleyes:

    WOW, like opening a courtain in front of the speakers, sounds a lot more lively, more in the room, did not test bass properly, but with jazz and classical music, I dont hear any significant change in bass quality, maybe a bit more articulate... :cool:

    It is amazing what one can do in 5 minutes, without spending one cent... :D

    [​IMG]
     
    melorib, Jul 28, 2007
    #1
  2. melorib

    JCL

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    I don't understand. Why is it better with the caps out ?

    I'm stupid.
     
    JCL, Jul 28, 2007
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  3. melorib

    melorib Lowrider

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    Sorry, its the problem of posts out of context, copied from another forum where they told me what to do... :rolleyes:

    I removed only the components of the feedback "circuit", one resistor and one cap from each channel...
     
    melorib, Jul 28, 2007
    #3
  4. melorib

    anubisgrau

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    you still have far too many parts over there, carry on...
     
    anubisgrau, Jul 28, 2007
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  5. melorib

    Antony

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    Is the circuit designed to run with zero NFB?
     
    Antony, Jul 28, 2007
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  6. melorib

    melorib Lowrider

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    Exactely my thoughts... ;)

    The input relays PCB plus all extra RCAs are allready removed...

    I could also remove, the 3 "parts" on top right corner that are disabled, selector, volume and time counter, plus the rectifier bridge that fed them...

    Then there are all those parts in the bottom right, between input board and output transformer, I guess for triode mode, that I also dont use... :rolleyes:
     
    melorib, Jul 28, 2007
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  7. melorib

    melorib Lowrider

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    If it was, it wouldnt do it, I guess... :rolleyes:

    But I read somewhere about a guy that did it in another EL34 amplifier, then I asked around and the "experts" told me that it wouldnt be a problem, global feedback lowers distortion and increases damping factor, but it also "spoils" mids and highs...

    I found someone that did it to one like mine, but in the end even increased the NFB because he preferred with is "normal" speakers, mine are probably easier to drive, as they are fullrange drivers, no crossover...
     
    melorib, Jul 28, 2007
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  8. melorib

    Stereo Mic

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    I have to say the quote below should be born in mind. Your reaction to increased distortion is most interesting.

     
    Stereo Mic, Jul 28, 2007
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  9. melorib

    melorib Lowrider

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    NFB reduces some kinds of distortion, adds others, I have the right to choose, dont I... :confused:

    My amplifier already was bad considering your criteria, only 6db global feedback, you dont have to use it any way, dont worry... :newbie:
     
    Last edited by a moderator: Jul 29, 2007
    melorib, Jul 28, 2007
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  10. melorib

    Stereo Mic

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    Good grief Antonio. I was only pointing out the facts. No need to be so touchy. As Rod said, if you like the sound of increased distortion then that's fine - a lot of people do.

    What distortion does NFB increase by the way? That's new to me.

    For what it's worth, my amplifer allows the selection of differing levels of global feedback from 3db to 12db. As it's reduced of course the distortion increases, but that can sound nice on less revealing systems.
     
    Stereo Mic, Jul 28, 2007
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  11. melorib

    Antony

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    Antony, Jul 28, 2007
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  12. melorib

    melorib Lowrider

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    The Negative Effects of Feedback

     
    melorib, Jul 28, 2007
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  13. melorib

    melorib Lowrider

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    Why do you think my system is less revealing than yours... :confused:
     
    melorib, Jul 28, 2007
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  14. melorib

    Paul Ranson

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    The quote is complete tosh.

    Paul
     
    Paul Ranson, Jul 28, 2007
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  15. melorib

    Robbo

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    Because of the speakers he uses. Trust me, it is more revealing. Not just compared to your system, but to 99.9% of other systems.
     
    Robbo, Jul 28, 2007
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  16. melorib

    Stereo Mic

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    Couldn't put it better Paul.
     
    Last edited by a moderator: Jul 29, 2007
    Stereo Mic, Jul 28, 2007
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  17. melorib

    dcathro

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    dcathro, Jul 29, 2007
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  18. melorib

    melorib Lowrider

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    Have you heard my system, how can you say that... :confused:

    I have heard too many systems with good components that sound VERY bad, also, if his system cannot show differences between cables, I doubt it has much resolution, then again, could be his hearing... :rolleyes:
     
    melorib, Jul 29, 2007
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  19. melorib

    melorib Lowrider

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    Very good... :D

    As usual, audio morons advocate blind tests for cables, then dismiss blind tests when the result doesnt suit their retarded theories... :rolleyes:
     
    melorib, Jul 29, 2007
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  20. melorib

    Robbo

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    I didnt think you'd get it.

    TAD horns. Those who know about them will understand.

     
    Robbo, Jul 29, 2007
    #20
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