Pros and cons of biasing with a scope ?

Discussion in 'Marshall Amps' started by Kelia, May 17, 2020.

  1. Exojam

    Exojam Well-Known Member

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    Amp,

    Than how about you write up what was taught to you and post it so others can see the exact way a Marshall should be biased.

    If you have already posted those steps if you could please point me to them that would be great.

     
  2. Kelia

    Kelia Well-Known Member

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    So if an amp is biased with the perfect sine wave on a scope ,
    what would be the dissipation result ,.60 -65-70 % or it differs from
    an amp to the other ?
     
  3. anitoli

    anitoli Well-Known Member Gold Supporting Member

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    If a 6l6GC tubes max is 23W then 70% would be 16W. And ironically 16 is where by ear i always thought the amp sounded best, any higher and it seemed too much.

    The scope method gets it very close. Now granted my scope is old and the trace isn't as sharp as it once was but if i reduced that cross over notch just a tad it would put me at 16W.
     
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  4. What?

    What? Well-Known Member

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    I guess the nice thing about a scope is that you get to see the bias set correctly. It doesn't seem necessary, but I suppose it gives some visual reassurance.
     

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