4100 diode clipping. When?

Discussion in 'Marshall Amps' started by Kutt, Dec 2, 2021.

  1. Kutt

    Kutt Well-Known Member

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    Not another nauseating JCM 900 debate thread. Just one question.

    I've read conflicting info on when, exactly, the clipping diodes kick in when turning up the gain controls on a 4100 Dual Reverb. Is it immediately at 1? Half way? Other?
     
  2. Tatzmann

    Tatzmann Well-Known Member

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    Everything bullshit.

    The 900DR is a Hybrid Amp.

    The Preamp is all ICs and Diode
    clipping on top of that.

    The Poweramp is standard Tube PA.

    The 12AX7s add nothing to the
    Distortion. Even the 12AX7 in
    the cathode follower can be taken
    out and the preamp still works, just
    quieter. Because its partially bypassed.

    Most stupid design masterpiece award
    goes to 900DR.
     
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  3. Kutt

    Kutt Well-Known Member

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    Anyone have a non-idiotic reply that actually relates to the question? Notably, it helps to read and comprehend what's being asked.
     
  4. Tatzmann

    Tatzmann Well-Known Member

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    Why are you asking when the clipping
    diodes kick in? Its all Transistordistortion
    anyways.

    Butthurt because you now realize that
    you got a bogus Marshall?
     
  5. Kutt

    Kutt Well-Known Member

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    Here's some great life advice I learned when I was about 7 years old- If you don't have anything useful to add to a conversation, stay out of it.
     
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  6. Tatzmann

    Tatzmann Well-Known Member

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    You should get your impedance checked
    Dude.
     
  7. Tatzmann

    Tatzmann Well-Known Member

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    I dont like to be called an Idiot for giving
    an realistic answer to your problem.

    So here i tell you again very slooowly when
    your Diodes "kick" in...

    As soon as you hear distortion from
    the preamp then your Diodes "kicked"
    in...

    Get it?:idea:
     
    Last edited: Dec 2, 2021
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  8. South Park

    South Park Well-Known Member

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    Diode clipping is full time on the gain . It is the same circuit as the pedals use .
     
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  9. scozz

    scozz Well-Known Member Gold Supporting Member

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    Nice, calm, concise, lucid answer.


    Thanks for that SP!
     
  10. gregr

    gregr Well-Known Member

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    I kinda like “If I wanted your opinion I would have beaten it out of you.”
     
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  11. iron broadsword

    iron broadsword Well-Known Member

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  12. gregr

    gregr Well-Known Member

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  13. jeffb

    jeffb Well-Known Member

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    I'm not a tech guy and had no idea of the particulars, but no wonder I hated that amp with a passion.

    Does the MKIII have the same "issue"? (I use quotes because for me it is, for some it's not)
     
  14. Tatzmann

    Tatzmann Well-Known Member

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    Nice calm and totally wrong and unprecise
    answer.

    If they were always "on" you could not
    have a clean sound or could you?
    Hogwash...as i said
    5000 posts before...as soon as you hear
    distortion from the preamp the diodes cut
    the highs and lows of the sinewave which
    results in distortion or better limiting.

    But he has a fan i guess. Lmfao.
     
  15. gregr

    gregr Well-Known Member

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    It sounds to me like the OP is mistaking the DR for the Mk III since there is a direct answer to that question.

    In the Mk III, the preamp control gets the tubes clipping, whereas the sensitivity control drives the diode/bridge rectifier into clipping. Your ears will tell you when (for the most part). I’m not entirely sure what’s going on with the gain stage before the cathode follower when the sensitivity is set low. I believe it should already be clipping.

    The two amps sound different from one another, as does the SL-X for that matter.
     
    Last edited: Dec 2, 2021
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  16. Tatzmann

    Tatzmann Well-Known Member

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    The original post stated 4100DR.
     
  17. jeffb

    jeffb Well-Known Member

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    Thanks. I need to go find a MKIII to give another whirl. Good bud of mine had the 50W head for many years, and finally had to move it- He gave me first dibs at a great price . I wanted to give it a whirl but I just couldn't fund it- he hit me up right as I was between jobs after a layoff.
     
  18. gregr

    gregr Well-Known Member

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    It’s a good amp but it’s not legendary. I have the 9th 2500 off the line, but I’m pretty sure Kelia has me beat.

    I like to run it in triode. It makes it smooth and creamy and gives it some squish. The amp has its own character this way. Kinda like how a VM is a Marshall but has its own sound.

    You can get all sorts of places using the controls on your guitar with the amp up loud. I don’t know that is has a lot of that treble bloom that you like, however.

    I like to push it with a TS to get it into saturation for high gain shredding, but I think the wheelhouse of this amp is mid-gain. An SD-1 can add aggression, otherwise I don’t consider it an aggressive amp.
     
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  19. Kutt

    Kutt Well-Known Member

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    Thanks to nearly all of you for the useful input.

    No desire to mod the amp. There is no problem with the amp. It is not my only amp. I look forward to keeping it for decades to come.

    Fact is, the thing sounds really really fkucking good dimed through my BOSS Tube Amp Expander with the output section cooking and I had a simple technical curiosity about this one aspect of the diodes. I have zero curiosity about diatribes.

    TTFN
     
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