Is there any pedal like the Rat but based on JFets instead of OP Amps?

Discussion in 'Effects, Pedals, Strings & Things' started by imguitardan, Jan 2, 2008.


  1. imguitardan

    imguitardan Member

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  2. fr8_trane

    fr8_trane Member

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    not that i know of but you can replace the clipping diodes with mosfet transistors. Beavis audio has a pedal called the FKBII (four knob rat) which is a tricked out rat with switches for all kinds of different clipping schemes including the mosfet clippers.
     
  3. screamingduck

    screamingduck Member

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    I have one and although it is quite versatile I finally have come to the conclusion that my Rat days are long over and I am more of a low gain player. Still a great pedal with several outstanding tones available
    from LED to Mosfet to symmetrical to assymetrical clipping. Very thought out well designed unit.
     
  4. justonwo

    justonwo Member

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    I believe Freakshow will build you a custom Brown Rabbit. Shoot them an email and ask.
     
  5. spentron

    spentron Member

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    Which part of the Rat do you want? The Op amp is part of its distortion section. You could drive the clipping diodes with a JFET preamp. You could use similar pre-distort bass cut (many do). You can follow almost anything with a version of the Filter.

    The one thing is it won't be a Rat.

    (wow, actually found said something to say that's allowed here)
     
  6. rewog

    rewog Member

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    Exactly.
    The RAT gets a major part of it's characteristics from using a particular opamp in a particular way (distortion induced by virtue of the low slew rate of the opamp).
    You could build a JFET distortion, and voice it with a similar tone, but it won't be a RAT.
     
  7. Skreddy

    Skreddy Member

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    To make it with FETs instead of an opamp, you could either just make a simple FET booster with clipping diodes and a simple tone control, or you could try to duplicate the LM308 opamp using discreet FETs. Not recommended...
    [​IMG]
     
  8. imguitardan

    imguitardan Member

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    Thanks for all the help. I'm into checking out the Beavis FKR but really don't think I could navigate all those options. I think a JFet OD/Dist that's voices and controlled like a Rat'd be nice.
     
  9. speed12

    speed12 Member

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    Definitely not a Rat and is probably a bit higher gain, but the Subdecay blackstar is a JFET distortion. Apparently it is a sort of a Liquid Sunshine with a built in boost to kick the gain over the top (ok, its a lot more complicated than that, but thats the simple semi-explanation given on the website!), so if thats a bit too high gain, then maybe a liquid sunshine with a seperate clean boost so you can adjust the actual boost level?

    Possibly......and again it wont really sound like a Rat at the end of the day!
     

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