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Passive high pass tone circuit for stompbox.

Discussion in 'Tele-Technical' started by Activateclint, Jul 30, 2020.

  1. Activateclint

    Activateclint TDPRI Member

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    Im building a stompbox/kickdrum box and want to add a capacitor that sends basically everything sharply above about 80hz to ground. Like the opposite of a low cut on a mixer channel. Id like it just plug in, dial in volume (on input on mixer with no eq option) and play, and not have to use the eq on the mixer. I've experimented with a few (green) caps and they either aren't enough and can still hear higher frequencies OR then start lowering overall volume.
    Do I need different caps?
    Do I need a resistor in there as well somewhere?
    Teach me stuff :)!
    I'm sure it can be done but I don't have the knowledge of electronics so I'm flailing around haha. I'll probably use a potentiometer once its figured out.
    Thanks
     
  2. wabashslim

    wabashslim Friend of Leo's

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    Passive roll-off is limited to 3dB/octave regardless of capacitor size. For more than that you'll have to go active (as far as I know).
     
    Last edited: Jul 30, 2020
    Activateclint and Deaf Eddie like this.
  3. tubegeek

    tubegeek Friend of Leo's

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    -6dB per octave for a single RC. Use multiple cascaded sections for steeper slope, or an LC passive filter.

    https://www.electronics-tutorials.ws/filter/filter_2.html

    https://www.electronics-tutorials.ws/filter/second-order-filters.html

    https://www.electronics-notes.com/a...ency applications,below the cut-off frequency.

    @Activateclint : what you want is a LOW PASS filter (same as High Cut.) A High Pass filter (same as Low Cut) will remove low frequencies below a specific frequency. You want the opposite.
     
  4. Activateclint

    Activateclint TDPRI Member

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    Thanks!
    Yea a LOW pass filter, i always get mixed up with whether its called whats passing to ground or through.
    Ok I've got some great info there, appreciate it!
    Looks like ill have a read and be able to mess about. Kind of makes a little sense to me more already :)
     
    tubegeek likes this.
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